Diaphragm valve made of fluororesin

Abstract

A structure of the manual diaphragm valve made of fluororesin, comprising an adjustment mechanism (7) configured to manually adjust an opening degree of the valve; the adjustment mechanism (7) is mounted on an upper valve cover (6a); the upper valve cover (6a) has a center hole (64) and one or more positioning holes (69); characterized in that: the adjustment mechanism (7) consists of a valve stem (4a), an adjustment seat (71), a C-shaped retaining ring (75), an adjusting wheel (74), a displacement indicator (76), an assembly of the positioning nuts (77) and an assembly of the locking nuts (78); the valve stem (4a) is a hollow stem and has a mounting end (41), a stem rod (42), a plurality of gas guide holes (413), a sliding part (45), a set screw thread (46), and a locking thread (47); the sliding part (45) is an axle with a pair of parallel cutouts; the adjustment seat (71) has a shoulder (711), a neck portion (712), an interior space (713), an external annular groove (716), a tool holder (717), and a stop post (719); the stop post (719) is coupled to the positioning hole (69) to hold the valve stem (4a) concentrically; the C-shaped retaining ring (75) has an external ring surface, an inner diameter hole (752), an opening part (753), two tool holes (754), a width B, and a thickness T; each assembly of the positioning nuts (77) and assembly of the locking nuts (78) consists of two nuts; the adjusting wheel (74) has a top surface (741), an external annular surface (742), an internal annular surface (743), an internal annular groove (744), a hub (745), an adjustment threaded hole (746) and a tool holder (747); the displacement indicator (76) in the form of a gate-shaped strip has a displacement space (761), a displacement scale (762), two mounting holes (763) and a center hole (764); the C-shaped retaining ring (75) is fully opened in the internal annular groove (744) and in the external annular groove (716); the internal annular groove (744) and the external annular groove (716) have an equal groove width W and are slidably attached to the thickness T of the C-shaped retaining ring (75); wherein the adjusting wheel (74) can be smoothly rotated on the adjusting seat (71); the sliding hole (718) is coupled to the sliding part (45) of the valve stem (4a), while the adjusting screw thread (46) of the valve stem (4a) is coupled to the adjusting thread hole (746) of the adjusting wheel (74).

Description

ENVIRONMENT OF THE INVENTION

[0001] The present invention relates to a diaphragm valve structure, particularly to a diaphragm valve made of fluororesin materials such as PTFE, PFA, etc. It has high corrosion resistance and an extremely low heat transfer coefficient of approximately 0.25 W / (mK), which is significantly lower than the heat transfer coefficient of approximately 30 W / (mK) of ceramic alumina Al2O3. This extremely low heat transfer property enables this type of material to withstand a high-temperature operating environment of 250°C. However, when the fluororesin diaphragm valve is used at high temperatures, the operating pressure and structural strength it can withstand are greatly reduced. Due to user needs, the demand for high-temperature, low-pressure, and high-purity fluid transportation with a temperature of ≤200°C is gradually increasing.The demand for high-temperature environments and high reliability is also increasing. It remains a major challenge for a diaphragm valve made entirely of fluororesin to operate with high reliability in a high-temperature environment of 200°C. BACKGROUND OF THE INVENTION

[0002] Fluororesin diaphragm valves are referred to as fluororesin valves in this patent. A manually operated valve is called a manual valve. A pneumatically operated valve is called a pneumatic valve. The fluororesin valve is the collective name for both the manual valve and the pneumatic valve. A metal diaphragm valve consists of a metal diaphragm, a fluororesin valve seat, a fluororesin liner, and a fluororesin membrane. The manually operated valve is referred to as a manual metal valve. The metal valve is the collective name for the aforementioned metal diaphragm valve.

[0003] The diaphragm valve has a long history and is widely used. The actuation method of this valve is manual, pneumatic, or electric. The parts or structures of the fluid contacting parts are made of metal, plastic, plastic lining, fluorine material, fluoroplastic lining, etc.

[0004] The state-of-the-art metal valve can operate smoothly at high temperatures and high pressures with a simple structure, withstand pipeline pressure waves, and is made of corrosion-resistant metals for transporting mildly corrosive fluids. The pneumatic or manual pressure-resistant structure, or the valve opening degree adjustment mechanism, can fully utilize the high rigidity of metal materials. For example, the tensile strength of cold-rolled 304 stainless steel sheet is 520 MPa, while the percentage elongation is about 40%. For example, the operating fluid temperature of an all-metal valve seat can reach 300°C or 350°C at 10 kg / cm 2 without the need for cooling. The temperature of the operating fluid of a PFA valve seat can reach 200°C at 10 kg / cm 2 The maximum working pressure of a high-pressure metal valve can reach 100 kg / cm2 at 80°C, while the valve seat is made of PCTFE. State-of-the-art metal valves exposed to high temperatures and severe corrosion may incorporate a fluororesin lining supported by a metal structure. Currently, the conditions for high-temperature resistance are limited by the temperature resistance of the fluororesin, which can reach 200°C or <250°C, depending on the structure.

[0005] An opening adjustment mechanism for a conventional manual metal valve essentially consists of a valve stem, a diaphragm, a handwheel, a support disc, an upper valve cover, and a threaded hole. The support disc has a T-shaped groove for attaching a T-shaped end of the valve stem. Several radially ribbed plates of the support disc engage with several radially ribbed plates on the inside of the upper valve cover. The diaphragm is attached to the underside of the support disc. Depending on the type of valve stem transmission, two types can be distinguished:

[0006] In the first type, the valve stem rotates, while the stem hole of the upper valve cover is the threaded hole, and the valve stem is screwed into it. The handwheel is mounted on the other end of the valve stem to directly drive the valve stem to rotate. The handwheel moves up and down with the valve stem. The valve stem can be rotated in the T-shaped groove.

[0007] In the second type, the valve stem does not rotate, while the threaded hole is formed in the inner hole of a positioning nut. The positioning nut is positioned and mounted on the stem hole of the upper valve cover and coupled to the valve stem. The handwheel is rotatably attached to the positioning nut, while the valve stem cannot rotate in the T-shaped groove, i.e., the support disc serves as an anti-rotation device.

[0008] The transmission methods of these two types each have the following basic structural functions: Function 1: The threaded hole for positioning, which is exclusively formed in the first type, is positioned and formed on the stationary structure of the manual metal valve, such as the stem hole of the upper valve cover, so that the valve stem and the threaded hole are coupled to move the valve stem up and down. Function 2: Positioning nut, which is exclusively for the second type. The center hole of the positioning nut is a threaded hole. One end of the positioning nut has a flange, while the other end can be fixed to the handwheel. When the positioning nut is installed in the shaft hole of the top bonnet, the end with the flange is located inside the top bonnet, while the end fixed to the handwheel is outside the top bonnet. The sliding surface on the bottom of the shaft hole of the handwheel can be coupled with the sliding surface on the outside of the center hole of the top bonnet to achieve an axial positioning function. Function 3: The anti-rotation diaphragm, exclusive to the first type, incorporates a mechanism to prevent rotation or torque on the valve stem. For example, the carrier disc has a T-shaped groove to secure the T-shaped end of the valve stem, with the diaphragm installed under the carrier disc. The carrier disc and the upper valve cover no longer rotate, preventing torque from acting on the diaphragm. Function 4: The valve stem with an anti-rotation device is exclusive to the second type. The anti-rotation device on the valve stem also prevents the diaphragm from rotating. Since the positioning nut is turned by the handwheel, the valve stem cannot rotate, and the rotation of the upper and lower sliding mechanisms must be stopped. The T-shaped groove on the support disc, for example, also serves as an anti-rotation device for the valve stem.

[0009] That is, the first type of transmission has two functions: a pair of threaded holes and a diaphragm with an anti-rotation device. The second type of transmission has two functions: a positioning nut and a valve stem with an anti-rotation device. To complete the functions of the second type of transmission, a handwheel, an upper valve cover, a positioning nut, several screws, and a support plate are required, a total of five parts.

[0010] The Fig. 9 shows a prior art lined manual metal valve 8. The opening degree of the valve is controlled by an adjustment mechanism. The valve stem transmission is of the second type. The manual metal valve 8 consists of a valve body 80, a diaphragm 81, a support disc 82, an upper valve cover 83, a valve stem 84, a positioning nut 85, a position indicator 86, a handwheel 87, and a plurality of bolts (e.g., a bolt set) 88. The valve body 80 is a metal valve body with a fluororesin lining and has an outlet 801, an inlet 802, a valve chamber 803, and a sealing surface 804. The support disc 82 is made of a metal material and has a T-shaped groove 821 and a plurality of ribbed plates 822. The membrane 81 consists of a central part 811, a peripheral part 812 and a rubber base 813.The positioning nut 85 has a threaded hole 851, a rotating ring 852, a fastening ring 853, a flange 854 and a positioning screw 855. .

[0011] The handwheel 87 has a center hole 871, a square hole 872, a fastening screw hole 873, and a sliding surface 874. The valve stem 84 has a T-shaped stem end 841, a set screw head 842, and an end piece 843. The upper valve cover 83 has an axle hole 831, a plurality of ribbed grooves 832, a sliding surface 833, a plurality of screw holes 834, a clamping surface 835, and a positioning hole 836. The T-shaped stem end 841 of the valve stem 84 is attached to the T-shaped groove 821 of the support disc 82. The diaphragm 81 and the rubber pad 813 are mounted under the support disc 82. The positioning nut 85 is mounted in the axle hole 831 of the upper valve cover 83. The valve stem 84 is located inside the upper valve cover 83.

[0012] The square hole 872 of the handwheel 87 and the fixing ring 853 are secured with fixing screws 875, so that the handwheel 87 is mounted in the axial position and is located on top of the upper valve cover 83, and the sliding surfaces 833 / 874 of the two are coupled. The valve stem 84 protrudes through the positioning nut 85 and through the center hole 871 of the handwheel 87. The position indicator 86 is mounted on the end piece 843. The plurality of ribbed plates 822 of the support disc 82 are coupled to the ribbed grooves 832 of the upper valve cover 83. After completing the above-described assembly, the upper valve cover 83 and the diaphragm 81 are fixed to the valve body 80. The peripheral part 812 of the diaphragm 81 and the clamping surface 835 of the upper valve cover 83 are firmly attached to the sealing surface 804 with the plurality of bolts 88.When turning the handwheel 87 to open the valve to the required height, the positioning screw 855 protrudes through the positioning hole 836 of the upper valve cover 83 so that the positioning nut 85 cannot be turned and the valve stem 84 cannot be moved.

[0013] The prior art metal valve 8 described above has two technical points. One represents the sealing mechanism, while the other represents the adjustment mechanism, as the following description shows: Sealing mechanism: The peripheral part 812 of the fluororesin diaphragm 81 is secured annularly to the clamping surface 835 of the upper valve cover 83. The high-pressure sealing effect is achieved by the metal structure of the high-strength valve body without cooling. The rubber pad 813 cannot withstand high temperatures. Adjustment mechanism: The first and second types are easy to implement because the metal rigidity can easily fulfill the adjustment function. As long as the positioning screw 855 is used to tighten the positioning nut 85 and the upper valve cover 83 in the positioning hole 836, the valve opening degree can be fixed. The metal adjusting screw head 842 can withstand the pressure waves of the pipeline.

[0014] As explained above, the manual metal valve is characterized by its simple structure and easy operation. However, when transporting a corrosive liquid, highly corrosive molecules easily penetrate the diaphragm even in small amounts. After a period of time, the metal thread easily corrodes and can no longer be rotated, posing a risk of metal contamination in high-purity processes. This is why many processes rely exclusively on fluororesin valves.

[0015] The tensile strength of fluororesin PFA is 29 MPa, the elongation percentage is >300%, and the melting point is 280°C. This strength decreases significantly with increasing temperature. The working pressure of the state-of-the-art fluororesin diaphragm valve is 5 bar at 90°C and 1 bar at 150°C. Furthermore, a PTFE filter housing, similar to a container structure, has a maximum operating temperature of 210°C and a working pressure of 7 bar at 70°C.

[0016] The structure of the fluororesin diaphragm valve is incomparable to that of a metal diaphragm valve in terms of temperature and pressure resistance. To meet the requirements of high temperature and high pressure, the manual valve has three technical features: thermal insulation, a sealing mechanism, and an adjustment mechanism, as shown in the following description: Thermal insulation: The thermal insulation method includes a heat transfer limiting structure and a heat dissipation structure that isolates the heat source area from the high-temperature chemical fluid and the structure requiring structural rigidity, and provides adequate cooling, including internal cooling. This allows the structure to be kept at a lower temperature to maintain structural rigidity and increase the operating temperature of the diaphragm valve. Sealing mechanism: The high elongation and the use of a fluorine material with the same hardness as the annular seal cause the material to move under the compressive and tensile deformation of the diaphragm, leading to the failure of the annular seal. The consequences are more severe at high temperatures, but this situation can be greatly reduced by thermal insulation. Adjustment mechanism: The valve opening adjustment mechanism cannot directly utilize the thread of the valve stem to withstand the pressure wave from the pipeline. Transmitting the pressure wave to the entire structure requires a locking mechanism and a transmission mechanism. Thermal insulation can maintain the rigidity and accuracy of the structure.

[0017] Currently, the demand for fluororesin valves with high temperature and pressure resistance continues to grow. Before 2018, most fluororesin diaphragm valves were used for medium and low temperatures (<120°C); they were specifically designed for use at high temperatures (<150°C); the operating pressure at normal temperatures is 3 kg / cm 2 up to 5 kg / cm 2After 2018, a new pneumatic diaphragm valve made of fluororesin was proposed. In 2020, Taiwan Patent Publication No. TW 202010966 A described a diaphragm valve structure and thermal insulation method. It can operate at 160°C without forced gas cooling and at 200°C with forced gas cooling. The working pressure at room temperature is 5 kg / cm 2 up to 7 kg / cm 2 , which prevents contamination of metal parts in the high-purity process.

[0018] The following problems 1 to 5 are the core problems in manual valve applications at high temperatures. The thermal insulation has been further improved and the sealing structure reinforced to meet the new requirements, since the operating temperature without cooling is 200°C, the temperature requirement with forced cooling is 230°C, and the ambient temperature is ≤100°C.

[0019] Problem 1. Operating temperature: The state-of-the-art high-temperature thermal insulation method must be applied and further improved, and its structural strength must be further reinforced. The heat transfer limiting structure consists of high-strength, grid-shaped, ribbed plates with multiple horizontal openings, which must be further reinforced to allow the cooling gas to flow through the sealing structure.

[0020] Problem 2. Ambient temperature: the special ambient temperature is ≤100°C, while the general ambient temperature is <60°C.

[0021] Problem 3. Annular sealing: The peripheral part is tightened by the diaphragm's sealing ring. When the peripheral part is subjected to pressure waves, the material of the peripheral part moves due to the expansion of the diaphragm, especially the movement of the material of the peripheral part. High temperatures deteriorate the mobility of the material, causing the sealing of the peripheral part to fail and leak. The reliability of the sealing mechanism can be improved if the diaphragm's sealing ring can prevent the movement of the material of the peripheral part.

[0022] The three problems mentioned above cause material creep to lead to diaphragm leakage. In addition to the aforementioned thermal insulation method, it is necessary to increase the strength of the sealing structure to solve the leakage problem caused by material creep. The conventional annular seal is usually achieved by a C-shaped clamping structure. A force introduction element located above the diaphragm presses the diaphragm against a sealing surface of the annular part to form a C-shaped sealing structure. The force introduction element is fixed to the valve body with a thread or a bolt. The C-shaped clamping structure consists of a clamping part, support arm, and a base. The force introduction element is used as the clamping part. The support arm serves as the valve body. The base is the peripheral part of a valve chamber of the valve body and serves as the sealing surface.The force application element is moved downward by firmly snapping into place, clamping the compressed diaphragm to prevent leakage. It is helpful to use a heavy structure for the force application element above the diaphragm and valve body to ensure annular tightness. However, at high temperatures, such a heavy structure without thermal insulation may cause deformation. This results in the valve stem being unable to be centered, shortening its service life. Other parts that do not require centering, such as pipe joints, are not a problem when using the heavy structure at high temperatures.In response to the above three problems with acceptable test standards, the baking temperature is 200°C with a baking time of >-6 hours after the diaphragm of the tested fluororesin valve is tightly attached to the parts in contact with the fluid. At normal temperature without any adjustment, the leakage is tested under high pressure, with the high pressure >= 10 kg / cm. 2 Only through such a test without leakage can it be demonstrated that the sealing structure can still meet the requirements for high airtightness under high-temperature operation.

[0023] The innovative core of the adjustment mechanism is to transmit the pressure wave to the valve body to solve the following problems: Problem 4. Valve stem damage: The valve stem of the manual valve is a separate part. The pressure wave transmitted directly from the upstream side directly impacts the diaphragm at the valve inlet and is transmitted to the valve stem and exerted on the valve stem thread. If the screw thread is damaged, it will cause internal leakage in the pipeline because the tightness cannot be guaranteed. Problem 5. Position locking: The valve stem of the manual valve cannot be locked after positioning, and its opening degree is affected by the pressure wave, which can easily affect the adjustment. The adjustment mechanism must be locked to the body after positioning.

[0024] The necessary additional functions of the adjustment mechanism must solve the following problems: Issue 6. Position indicator: A valve opening indicator is a very common device for fluororesin valves. Pneumatic valves only have an ON / OFF indicator, but many products still lack such a device. Manual valves must be able to continue to display the valve opening after adjustment. Problem 7. Positioning distortion: The diaphragm of the manual valve is deformed by the play and the structure of the coupling screw thread, causing the center of the diaphragm and the valve seat to be deformed, resulting in positioning distortion. Zeroing the positioning and correctly displaying the valve opening position are necessary. However, such a requirement for pneumatic valves is rare. Problem 8. Diaphragm overpressure: The manual valve must be able to effectively control the sealing force. However, positioning distortion can cause the diaphragm to lock too tightly, resulting in damage to the diaphragm and valve seat. However, such a requirement for a pneumatic valve is rare. Problem 9. Incorrect operation: After completing the adjustment of the opening degree of the manual valve, the valve shall not be incorrectly operated by uninvolved persons.

[0025] The adjustment mechanism must be able to provide a leak warning to solve the following problems: Problem 10. Leak warning: Most leaks are caused by the penetration of corrosive liquid molecules. Small-molecule liquids, such as hydrofluoric acid and hydrochloric acid, can penetrate the diaphragm in small amounts. The valve stem must be equipped with a stem seal to delay the spread of acid gas. If the diaphragm has a slight leak, a leak warning is required, or the leaked liquid can be collected. This is relatively common in pneumatic valves and less common in manual valves. The fluororesin valve must have this function in the future.

[0026] In the past, users had some similar requirements to these ten requirements and used some of the prior art to meet their needs. However, it is necessary to solve the above ten problems simultaneously for the same manual valve in order to make the manual valve more practical and effective with high reliability. That is, solving the above ten problems at the same time is the new requirement for the manual valve. The sealing mechanism of these technologies is also very valuable when incorporated into a pneumatic valve, but the pneumatic valve does not need to use an adjustment mechanism. The references of the prior art are described below. Reference 1

[0027] With reference to the early US Patent Publication No. US 2020 / 0 072 384A1 from 2020 entitled "Structure of a Diaphragm Valve", the invention is also disclosed in Taiwan Patent Publication No. TW 202010966 A entitled "Structure of a Diaphragm Valve". The embodiment relates to a pneumatic valve that enables thermal insulation, but whose sealing mechanism does not meet the new requirements. The core of the solution lies in the thermal insulation method and its unique structure. The heat source section of the diaphragm valve includes a valve chamber heat source section, a flow channel heat source section, a inlet pipe heat source section, a outlet pipe heat source section, a inlet nozzle heat source section, and a outlet nozzle heat source section.The high-temperature thermal insulation method for the valve body includes a heat transfer limiting structure and a heat dissipation structure. The heat transfer limiting structure is attached to a square part, an annular part, and the minimum diameter portion of the annular part of the valve body. The square part is equipped with high-strength, lattice-shaped finned plates with horizontal openings to reduce the cross-sectional area for heat transfer and enhance external heat dissipation. The annular part has multiple vertical finned plates for heat dissipation. The minimum diameter portion has a heat transfer limiting cross-sectional area, so that the valve stem and cylinder structure can reduce heat transfer and achieve cooling.The internal cooling gas of the heat dissipation structure flows through the cooling gas hole and the annular gas groove of the valve body, through the cooling gas guide hole of the upper valve body, and then through the gas guide hole and the valve stem shaft hole. The high-temperature thermal insulation of the valve body features a unique structure designed to meet the requirements of high-pressure gas propulsion, static elimination of the fluid, sealing the valve body from metal parts, sealing the valve body from non-metal parts, preventing structural creep, releasing particles, leak detection, and valve stem position indication. This valve can operate at 160°C without forced gas cooling and at 200°C with forced gas cooling. The working pressure at room temperature is 5 kg / cm. 2 up to 7 kg / cm 2. It also solves the problem that process engineers need to pay attention to the pollution caused by the corrosion of metal bolts from time to time. This reference takes a pneumatic valve as an example and proposes a good basic solution for the operating temperature (problem 1) and the ambient temperature (problem 2). Unfortunately, it still does not meet the current requirements of an operating environment at a temperature of 200°C without cooling by a gas. This reference provides the solution for the annular tightness (problem 3) in an operating environment at a temperature of 160°C without cooling by a gas. However, it cannot meet the new requirements of an operating environment at a temperature of 200°C without cooling by a gas. This reference takes a pneumatic valve as an example, and the opening degree of the valve only indicates ON / OFF.There is no solution for the diaphragm opening limit and valve stem damage (Problem 4). The valve stem position indicator (Problem 6) only has an ON / OFF indicator, without a diaphragm opening indicator. With this reference, position lock (Problem 5), positioning distortion (Problem 7), diaphragm overpressure (Problem 8), and incorrect operation (Problem 9) in the pneumatic valve are not very common. This reference provides a perfect solution for the leak warning (Problem 10).

[0028] In this reference, the valve has a substantially C-shaped clamping structure. The C-shaped clamping structure consists of a clamping part, a support arm, and a base. The force introduction element is an upper valve body. The support arm is the annular part of the valve body. The annular part has several vertical ribbed plates with heat dissipation function and structural reinforcement. The upper valve body is firmly fixed to the internal thread of the annular part. The minimum diameter range has a limit value for the cross-sectional area of ​​heat transfer. The base is the peripheral part of the valve chamber of the valve body as a sealing surface. The upper valve body is moved downward by firmly snapping, so that the tensioned diaphragm is clamped to prevent leakage.In this reference, the strength of the support arm of the C-shaped clamping structure is still insufficient for an operating environment at a temperature of 200°C without cooling by a gas. Reference 2

[0029] Chinese Utility Model No. CN 2 05 350 538 U of 2016 discloses a manual diaphragm valve, which is the first type of manual valve or manual metal valve and comprises a valve body and a handwheel actuator. The opening and closing of the diaphragm depends on the coupling of the thread of the valve sleeve under the handwheel and the thread of the valve stem. The valve stem has a position indicator passing through the center of the handwheel to indicate the position of the valve stem. It is characterized in that an upper locking part is fixed to the handwheel and a lower locking part is fixed to the upper valve cover. The upper locking part and the lower locking part each have a locking hole. A pin protrudes through the locking hole to fix the handwheel and ensure that the valve stem does not move up and down.

[0030] In this reference, the operating temperature (problem 1), the ambient temperature (problem 2), the annular tightness (problem 3), the valve stem damage (problem 4), the diaphragm overpressure (problem 8), the positioning distortion (problem 7), the incorrect operation (problem 9) and the leak warning (problem 10) are not described, so this reference cannot meet all the new requirements. Reference 3

[0031] Chinese Patent No. CN 1 02 758 935 A of 2012 discloses a structure of a diaphragm valve, which is the first type of manual valve or manual metal valve. The aim of this reference is to improve the problem of unclear positioning of the indicator disc on the valve stem of the manual valve and to propose a linear position indicator that moves simultaneously with the valve stem (Problem 6). This reference does not describe the operating temperature (Problem 1), ambient temperature (Problem 2), annular tightness (Problem 3), valve stem damage (Problem 4), position locking (Problem 5), positioning distortion (Problem 7), diaphragm overpressure (Problem 8), incorrect operation (Problem 9), and leakage warning (Problem 10), so this reference cannot meet all the new requirements. Reference 4

[0032] Chinese Utility Model No. CN 2 04 114 227 U from 2015 discloses a novel fluorine-lined diaphragm valve, which is the first type of manual metal valve. The objective of this reference is to improve the missing position indicator (Problem 6) on the valve stem, which leads to diaphragm overpressure (Problem 8) with excessive closing pressure during closing. This reference only proposes a solution for the position indicator (Problem 6). This reference does not describe the operating temperature (Problem 1), the ambient temperature (Problem 2), the annular tightness (Problem 3), the valve stem damage (Problem 4), the position lock (Problem 5), the positioning distortion (Problem 7), the diaphragm overpressure (Problem 8), the incorrect operation (Problem 9), and the leak warning (Problem 10), so this reference cannot meet all the new requirements. Reference 5

[0033] Chinese Utility Model No. CN 2 04 344 989 U from 2015 discloses a diaphragm valve, which is the first type of manual metal valve. This reference pursues two objectives. One is to improve the diaphragm, which must withstand instantaneous pressure, and the other is to prevent the diaphragm from being damaged in a high-temperature environment. The structure of this reference features a position indicator (Problem 6). The solution of this reference is to provide an opening in the center of the diaphragm on the side that does not come into contact with the liquid. An elastic member is inserted into the opening. The underside of the valve stem is in contact with the elastic member. This solves the problems of valve stem damage (Problem 4), positioning distortion (Problem 7), and diaphragm overpressure (Problem 8).This reference does not describe the operating temperature (Problem 1), ambient temperature (Problem 2), annular tightness (Problem 3), position locking (Problem 5), incorrect operation (Problem 9), and leak warning (Problem 10), so this reference cannot meet all the new requirements. The illustration of the prior art elastic element used in this reference shows that the metal spring is arranged above the diaphragm. At high temperatures and severe corrosion, the pumped liquid will be contaminated by the corrosion of the acid gas on the metal. This situation is unacceptable for process users. Furthermore, the countermeasures for high-temperature applications in this patent are limited to protecting the periphery of the diaphragm.This solution does not completely solve the annular seal (Problem 3), and it also poses the problem of diaphragm and structural creep due to high temperature. This reference cannot meet all the new requirements. Another similar reference from 2017, Patent No. TW 1670439 B from Taiwan, describes a manual wire valve for opening and closing that offers convenient operability and stable sealing properties when the handle is rotated. The manual metal valve also consists of a spring to perform similar functions. Reference 6

[0034] Chinese Utility Model No. CN 2 07 648 146 U of 2018 discloses a diaphragm valve, which may be the first or second type of manual metal valves. This reference relates to manual diaphragm valves for applications at a temperature not exceeding 200°C. In this reference, the valve body is equipped with a stopper, with a sensor connected to an external flashing bead so that the user cannot further compress the diaphragm when the diaphragm is closed, as this may lead to overpressure of the diaphragm (Problem 8). The valve stem has a position indicator (Problem 6). These two functions are convenient for users. Second, the valve disc is mounted at the lower end of the valve stem. An elastic rubber is provided between the valve disc and the fluororesin diaphragm.This can only partially solve the problems of annular tightness (Problem 3), valve stem damage (Problem 4), positioning distortion (Problem 7), and diaphragm overpressure (Problem 8). The high temperature also causes the elastic rubber to fail. The problems of incorrect operation (Problem 9) and leak warning (Problem 10) are not described. The diaphragm overpressure (Problem 8) is reduced by the stopper. This reference refers to a metal valve. The body of the fluorine valve is lined with a metal structure. It is suitable for high operating temperatures of 200°C (Problem 1) and can greatly reduce the problem of creep of the fluorine structure body, while also being suitable for high ambient temperatures (Problem 2). The high-strength adjustment mechanism of the metal stem does not require a position lock (Problem 5).This is the advantage of the fluororesin diaphragm valve lined with a metal structure. The valve can be used at a high operating temperature of 200°C without any design cooling measures (Problem 1). However, the diaphragm valve made entirely of fluororesin cannot readily fulfill this function and requires further consideration. Reference 7

[0035] Chinese Utility Model No. CN 2 07 906 557 U of 2018 discloses a high-temperature valve that uses a movable sleeve to construct a leak-free diaphragm valve, which is the first type of manual metal valve. The structure of this reference is a manual diaphragm valve suitable for high-temperature and high-pressure applications, where the opening degree of the diaphragm can be adjusted with an adjustment lever. However, this reference does not specify whether the valve body is made of metal. It mentions that the working pressure of the diaphragm valve is <10 bar. This situation mostly refers to metal valves, and fluororesin diaphragm valves cannot be realized due to material limitations. In this reference, the maximum rated pressure can reach PN63, and the maximum temperature is <=200°C.The pressure resistance is 5 times higher than that of the prior art and without any cooling, which is also the characteristic of metal valves. The special feature of this reference is that several support sleeves, connected to each other, are installed above the diaphragm and inside the valve cover. Under high pressure, the support sleeves move upward and adapt to the deformed shape of the diaphragm to improve the pressure-bearing capacity of the diaphragm. The support sleeves are more suitable for the use of heat- and corrosion-resistant plastics. This reference does not specify whether the above-mentioned maximum temperature and maximum pressure can be reached simultaneously. Since the same conditions are met, it must be a metal structure. The fluororesin structure cannot meet these operating conditions simultaneously.This reference refers to a metal valve suitable for high operating temperatures of 200°C (Problem 1). The limitation should be caused by the diaphragm material, which is suitable for high ambient temperatures (Problem 2). The support sleeves of this reference can solve the problems of annular tightness (Problem 3), valve stem damage (Problem 4), positioning distortion (Problem 7), and diaphragm overpressure (Problem 8). However, this reference does not mention the position lock (Problem 5). If the valve is a metal one, this problem can be circumvented. This reference proposes a leak warning (Problem 10), but the position indicator (Problem 6) can only be replaced by an adjustment lever, which does not prevent incorrect operation (Problem 9). Reference 8

[0036] US Patent No. 5,377,956 A, issued in 1995, discloses a diaphragm valve, which is the first type of manual metal valve. The structure of this reference is suitable for metal-lined manual valves that can adjust the opening degree of the diaphragm and prevent the problem of diaphragm overpressure (Problem 7). A nut, which moves with the handwheel, is mounted on the external thread of the valve stem. The top of the inside of a stem hole of the nut abuts the upper edge of the valve body. The outer edge of the nut has axial serrations (polygon teeth), which are coupled with serrations (polygon teeth) on the inside of the axial cylinder under a handwheel. That is, when the handwheel is rotated, the nut moves up and down in synchronization with the rotation of the valve stem.The handwheel has a square hole in the center that connects to the end of the valve stem, so the handwheel is secured to the end of the valve stem with a locking bolt. When manually opening the valve, the valve stem is rotated to the desired opening position using the handwheel. When the manual valve is fully closed, the handwheel is rotated until the nut rests against the upper edge of the valve body. This can avoid the problem of diaphragm overpressure (problem 7). To adjust the diaphragm opening degree, the locking bolt is loosened to remove the handwheel, readjusting the position of the valve stem. The position of the nut is lowered to the upper edge of the upper valve body, after which the handwheel is installed. The synchronization of the handwheel and the nut can prevent the valve from closing and maintain the valve opening degree.This reference refers to the metal-lined valve and does not mention the operating temperature (Problem 1), ambient temperature (Problem 2), annular tightness (Problem 3), valve stem damage (Problem 4), position indication (Problem 6), positioning distortion (Problem 7), incorrect operation (Problem 9), and leak warning (Problem 10). This reference uses the nut moved by the handwheel to overcome the problems of position locking (Problem 5) and diaphragm overpressure (Problem 8). The position locking (Problem 5) can only be locked downwards, but not upwards. This design can be accepted if the valve is a metal-lined valve. If the manual valve is subjected to pressure waves in the line, the valve stem will be damaged (Problem 4). In addition, the handwheel must be removed when adjusting the diaphragm opening degree.The operation proves to be impractical. Reference 9

[0037] US Patent No. US 2012 / 0 056 120 A1 from 2012 discloses a diaphragm valve, which is also published in CN 1 02 388 248 B from 2014, entitled "Diaphragm Valve." This represents the second type of transmission, which has two functions: a positioning nut and a valve stem with an anti-rotation device. Five parts are used to transmit the valve stem: a handwheel, a positioning nut, a support plate (pressure element), a pin, and a union nut.

[0038] Thermal insulation: No thermal insulation is provided for internal cooling. It cannot meet the requirements for high-temperature operation.

[0039] Sealing mechanism: The outer casing of the upper valve cover (the upper part of the casing) can be firmly fixed on the external annular surface of the valve body (receiving area). The outer casing presses the inner casing downward, so that the diaphragm is pressed against the bottom of the receiving area by the lower edge of the inner casing. This reference has a C-shaped clamping structure. This C-shaped clamping structure consists of a clamping part, a support arm, and a base. The force introduction element is an inner casing. The inner casing is firmly fixed in a receiving area of ​​a housing by an outer casing. The support arm is the receiving area of ​​the valve body. The base of the C-shaped clamping structure has no rigid support and is a very thick structure without thermal insulation. It cannot operate at a temperature of 200°C without gas cooling.

[0040] Adjustment mechanism: No solutions for the position lock (Problem 5) and the valve stem damage (Problem 4). The handwheel has a wedge sleeve connected to the positioning nut. The valve stem is secured against rotation by the axial movement of the carrier disc (pressure element) and simultaneously ensures the diaphragm's anti-rotation. A rubber pad is provided on the back of the diaphragm so that the diaphragm can be pressed directly against the inner housing.

[0041] This reference has three features. The main feature is that the flow channel has a smooth cross-sectional area. The flow channel between the inlet and outlet has an elliptical cross-section with equal area and smoothly transitions into the circular cross-section of the inlet and outlet. Second, the sealing mechanism and the upper valve cover (the upper part of the housing) consist of an outer housing and an inner housing.

[0042] Sealing mechanism: The outer casing is firmly fixed to the external annular surface of the valve body (receiving area). The outer casing presses the inner casing downward, so that the diaphragm is pressed against the bottom of the receiving area by the lower edge of the inner casing. The internal annular surface of the receiving area has several axial grooves, which are coupled with several axial projections on the external annular surface of the inner casing. When the outer casing is tightened, the inner casing is not rotated and seals the diaphragm well. This is a good solution to the annular tightness (Problem 3). However, the base of the C-shaped clamping structure lacks a rigid support, has a thick structure, and also lacks a structure for restricting heat transfer and a structure for heat dissipation. Third, the overpressure of the diaphragm (Problem 8). The handwheel is fixed to the positioning nut to rotate.One end of the valve stem coupled to the diaphragm is fixed to a union nut with a pin. A diaphragm fixing nut is installed in the union nut. The fixing nut has axial movement space. When the valve stem tightens the diaphragm, the axial movement space can reduce the diaphragm overpressure (Problem 8). This reference does not describe the problems of operating temperature (Problem 1), ambient temperature (Problem 2), valve stem damage (Problem 4), position locking (Problem 5), position indication (Problem 6), positioning distortion (Problem 7), incorrect operation (Problem 9), and leak warning (Problem 10). This reference can only be used at low temperatures and does not meet all the new requirements for high-temperature operation. Reference 10

[0043] Japanese Patent No. JP 2012-189088 A from 2012 discloses a manual valve that represents the second type of transmission and has two functions: a positioning nut and a valve stem with an anti-rotation device. Five parts are used to transmit the valve stem: a handwheel, a positioning nut, a bolt, a stem sleeve, and a pin.

[0044] Thermal insulation: No thermal insulation is provided for internal cooling. It cannot meet the requirements for high-temperature operation.

[0045] Sealing mechanism: The inside of the upper valve cover contains a sliding nut and a guide rod arranged in a vertical direction. The upper valve cover is firmly fixed to the internal annular surface of the opening side of the valve body, the bottom of the opening side is the valve chamber, while the positioning nut is tightened downward and the stem sleeve is tightened. The stem sleeve is fixed to the pump housing with a pin. The diaphragm is pressed directly against the lower area of ​​the valve chamber of the valve body by the lower edge of the stem sleeve. This reference features a C-shaped clamping structure. The C-shaped clamping structure consists of a clamping part, a support arm, and a base. The force introduction element is a hollow guide post. The guide post is firmly attached to an outer casing in a receiving area of ​​a pump casing. The support arm is the receiving area of ​​the valve body.However, the base of the C-shaped clamping structure lacks a rigid support, is thick, lacks a heat transfer restriction structure and a heat dissipation structure, and lacks thermal insulation. It cannot operate at a temperature of 200°C without gas cooling.

[0046] Adjustment mechanism: With position lock (Problem 5). The handwheel and positioning nut are secured with a screw. However, with a plastic structure, these parts are easily loosened or damaged. The valve stem is also damaged after prolonged use (Problem 4). The diaphragm is secured against rotation by the guide rod. This reference has three features. The main feature is the overpressure of the diaphragm (Problem 8). The manual mechanism is mounted in the upper valve cover. A stop ring is mounted on the valve stem structure to tighten a pressurized O-ring attached to the top of the stem sleeve. When the valve stem is moved down to close the valve, the stop ring initially compresses the O-ring. This can solve the problem of overpressure of the diaphragm (Problem 8) caused by excessive torque on the valve.Second, the sealing mechanism on the opening side of the valve body includes the top valve cover, the positioning nut, and the stem sleeve. The diaphragm can be tightened when the top valve cover is securely fastened. It has a thick structure, but no heat transfer limiting or heat dissipation structure is provided. Third, the adjusting knob of this reference is screwed to the positioning nut, and the positioning nut can be rotated. Once the correct opening degree is set, the positioning nut can be tightened with a screw on the top valve cover. The end piece of the valve stem has a position indicator (Problem 6). The valve stem can provide position locking (Problem 5). There is no damage to the valve stem (Problem 4) and no misoperation (Problem 9).However, during long-term use, problems with position locking (Problem 5) and valve stem damage (Problem 4) still occur due to material problems. This reference does not describe the problems of operating temperature (Problem 1), ambient temperature (Problem 2), positioning distortion (Problem 7), and leakage warning (Problem 10). This reference cannot meet all the new requirements for high-temperature operation. Japanese Patent No. JP 2020-37970 A from 2020 discloses a misoperation prevention cover and a manual valve with a misoperation prevention cover. The misoperation prevention device (Problem 9) consists of three parts: a fixing ring, a protective cover, and a detection section.This reference does not address the operating temperature (Issue 1), ambient temperature (Issue 2), valve stem damage (Issue 4), position indication (Issue 6), positioning distortion (Issue 7), and leak warning (Issue 10). This reference cannot address all new requirements for high-temperature operation.

[0047] Regarding the solutions of the above ten references, only the first reference proposes a high-temperature insulation solution, while the remaining references propose partial solutions at room temperature. That is, no reference meets the core requirements for manual valves that address problems 1 to 5. Problems 1 to 3 are not solved. The support arm of the C-shaped clamping structure of reference 1 has insufficient strength. The base of the C-shaped clamping structure of references 9 and 10 lacks firm support, is very thick, and no thermal insulation is provided. None of these three references meets the requirements at an operating temperature of 200°C without gas cooling. Position indication (problem 6) is a common practice.References 9 and 10 lack a better mechanism that simultaneously overcomes the problems of valve stem damage (Problem 4) and position locking (Problem 5) by using only a single bolt for the locking function. While installing a spring on the valve stem or adding a rubber element to the non-fluid contact side of the diaphragm can solve the problem of diaphragm overpressure (Problem 8), it is not specified whether it is suitable for use at a high operating temperature of 200°C, and it does not provide a better solution for position locking (Problem 5) and positioning distortion (Problem 7). Rubber material cannot be used at a high temperature of 200°C.If the elastic metal material is used directly on the non-liquid contact side of the membrane in a high-purity process, there is a risk of metal contamination. OBJECT OF THE INVENTION

[0048] A sealing structure of the present invention must satisfy the following test conditions to meet the requirements of operating temperature (Problem 1), ambient temperature (Problem 2), annular tightness (Problem 3), etc.

[0049] The test assembly includes only the assembly requiring high-temperature and high-pressure testing, including a valve body, diaphragm, upper valve body, sealing ring, valve stem, etc., excluding the retaining bracket of a valve top cover. The baking temperature is 200°C for a baking time of >=6 hours. When the tested fluororesin valve returns to normal temperature without adjusting the locking, only the required seals such as inlet and outlet ports are applied for the high-pressure leak test. The test pressure is >=10 kg / cm 2 without leaks.

[0050] Such baking without heat dissipation is more severe than the actual use conditions and fully tests the annular tightness (Problem 3) of the sealing structure. Creep of the structure at high temperatures can lead to deformation of the sealing surface and reduce the clamping force. The test can ensure normal operation at ≤200°C without forced gas cooling and highly reliable operation at ≤230°C when forced gas cooling is provided (Problem 1). It can also operate at an ambient temperature of 100°C of the ambient temperature (Problem 2), which means that the sealing mechanism completely solves the annular tightness problem (Problem 3).

[0051] The present invention is based on the technology of Reference 1, Patent No. TW 202010966 A of 2020, titled "Diaphragm Valve Structure" of Taiwan. It uses the prior art high-temperature thermal insulation method, including the heat transfer restriction method and the heat dissipation method, to develop an innovative sealing mechanism and an innovative adjustment mechanism. The innovation of the sealing mechanism is to reinforce the C-shaped clamping structure and generate a leak warning (Problem 10), which is suitable for pneumatic and manual valves.

[0052] A diaphragm valve made of fluororesin using the example of a manual valve.

[0053] The manual valve consists of a sealing mechanism and a valve part to propose innovation and find solutions to the problems of operating temperature (Problem 1), ambient temperature (Problem 2), and annular tightness (Problem 3). A fluororesin diaphragm valve structure is used to convey fluid at 200°C without forced external gas cooling. The differences in the components of the sealing mechanism are divided into a basic mode, a first implementation mode, a second implementation mode, a third implementation mode, and a fourth implementation mode.

[0054] In basic mode, the sealing mechanism of the fluororesin diaphragm valve includes related parts and mechanisms of a valve part. The valve part consists of a valve body, a force introduction element, a valve top cover, a diaphragm, and a seal ring. The valve body consists of an inlet, an outlet, a valve chamber, an annular part, and a square part. The annular part includes a sealing surface, an external annular surface, a minimum diameter area, an internal annular surface, and a ribbed plate structure. The annular part is a bowl-shaped structure with an opening. The bottom of the annular part is defined as the valve chamber. The opening is closed with the valve top cover. The valve top cover has an internal receiving chamber, an external annular surface, a top surface, and a center hole.

[0055] The diaphragm includes a peripheral portion, an elastic portion, and a central portion. One end of the valve stem has a fastening end that can lock the central portion of the diaphragm.

[0056] The sealing mechanism consists of the annular part, the ribbed plate assembly, the sealing surface, the diaphragm, the sealing ring, the force introduction element, and a clamping surface. The clamping surface is a structural surface of the force introduction element. The clamping surface attaches the annular part to the sealing surface, forming a C-shaped clamping structure. A clamping part of the C-shaped clamping structure encompasses the force introduction element.

[0057] The force application element is firmly attached to the annular part. A support arm of the C-shaped clamping structure ensures the overall structural strength of the annular part and the ribbed plate assembly. A substructure of the C-shaped clamping structure is the sealing surface, which is supported by the minimum diameter area, a side wall of the valve chamber flow channel, and the ribbed plate assembly. The clamping surface is moved downward by firmly engaging, so that the sealing ring and the diaphragm are clamped by the clamping surface and the sealing surface to prevent leakage.

[0058] The sealing ring is a ring-shaped structure with an approximately rectangular cross-section and has two ends, defined as a force-absorbing end and a tightening end. The tightening end is an obtuse angle.

[0059] The ribbed plate assembly is arranged on the external annular surface of the annular part and is an annular lattice structure with multiple horizontal openings. The ribbed plate assembly is axially fixed to the square part, with its axial position including the minimum diameter region structure, the sealing ring, and the clamping surface.

[0060] When installing the diaphragm in the valve chamber, the peripheral part is attached to the sealing surface. The clamping ring is fastened in the clamping groove of the force introduction element. The clamping surface exerts a force F on the force-absorbing end, so that the tightening end, which has the obtuse angle β, is tightened onto the peripheral part. The obtuse angle β is in the range of 110°≤β≤150°. When the force F is exerted on the sealing surface, it is supported by the ribbed plate structure of the annular part, as well as the square part and the side wall of the flow channel of the valve chamber. The clamping force F has a force introduction angle ε with a normal N of a force introduction surface of the peripheral part. The force introduction angle ε is in the range of 0°<ε≤15°.

[0061] The finned plate assembly is an annular lattice structure with multiple horizontal openings. The finned plate assembly is located on the outer annular surface of the annular part. One side of the finned plate assembly in the axial direction is fixed to the square part, with the distribution position having the minimum diameter area. The sealing ring is provided on the other side of the finned plate assembly in the axial direction. The minimum diameter area has a cross-sectional restriction for heat transfer to reduce heat transfer.

[0062] As the diaphragm expands and deforms under the pressure of the pipeline, the peripheral part is subjected to a force and tension, generating displacement. The peripheral part has a wedge-shaped cross-section with a larger thickness on its outer side and a smaller thickness on its inner side, which are attached to the elastic part.

[0063] The peripheral part has upper and lower side surfaces. The upper side surface is defined as the load-bearing surface, and the lower side surface as the mating surface. The mating surface and the load-bearing surface are neither flat nor conical. The mating surface is attached to the sealing surface of the annular part. The load-bearing surface is pressed firmly against it by the tightening end of the sealing ring. The sealing surface can be a conical or flat surface.

[0064] In the first embodiment, the external annular surface of the annular part has an external screw thread. The other side of the ribbed plate structure in the axial direction is fixed to the external screw thread. The upper valve cover consists of an internal receiving chamber, an external annular surface, an internal screw thread, a top surface, a stem boss portion, and has a center hole, as well as a ribbed seal plate. The force introduction element is the ribbed seal plate. The ribbed seal plate is arranged between the stem boss portion and the internal screw thread. A thread groove is formed between the annular ribbed seal plate and the internal screw thread. A stem boss groove is formed between the stem boss portion and the annular ribbed seal plate. A lower end of the annular ribbed seal plate has an annular clamping groove.An opening of the groove is formed opposite the internal screw thread and faces downward. The clamping surface is provided at an upper bottom of the clamping groove. The seal ring is fixed in the annular clamping groove. A plurality of radial ribs are formed between the stem boss portion and the annular ribbed seal plate to improve the strength of the ribbed seal plate and insulate the heat transmitted from the valve stem. When the upper valve cover is tightly closed with the annular portion, the structure of the annular portion is embedded in the thread groove. The external annular surface of the ribbed seal plate has a plurality of convex longitudinal ribs. The plurality of convex longitudinal ribs are adjacent to the internal annular surface of the annular portion to ensure the structural strength and insulate the heat transmitted from the peripheral portion of the diaphragm.

[0065] In the second embodiment, the force introduction element is an upper valve body. The upper valve body includes a locking thread, a stem hole, one or more annular grooves, a plurality of ribbed groove plates, a diaphragm chamber, and a clamping groove. The clamping groove has a clamping surface. The internal annular surface of the annular part is provided with an internal screw thread. The locking thread is firmly screwed to the internal screw thread. The upper valve body is firmly screwed to the internal screw thread. The sealing ring is fixed in the clamping groove. An axial distribution position of the ribbed plate structure includes the minimum diameter range and a plurality of screw threads of the external screw thread.

[0066] In the third embodiment, which is based on the second embodiment, the force introduction element is an upper valve body. The external annular surface of the annular part has an external screw thread. A plurality of screw threads of the internal screw thread and the external screw thread are overlapped in the axial position. The external screw thread is fastened to the ribbed plate structure. The upper valve cover has an internal screw thread that is screwed and engaged with the external screw thread of the annular part. The axial position of the internal screw thread of the annular part is limited by the axial length of the external screw thread and the ribbed plate structure.When the upper valve cover is tightly screwed to the external screw thread, several screw threads of the upper valve cover distributed in the axial direction of the internal screw thread and the locking thread of the upper valve body overlap.

[0067] In the fourth embodiment, which is based on the second embodiment, the force introduction element is an upper valve body. The axial distribution of the ribbed plate structure includes the axial distribution position of the internal screw thread of the annular part. The external annular surface of the upper valve cover has a plurality of spaced annular ribbed plates.

[0068] As for the sealing mechanism, when the sealing ring is tightened, it is deformed by a force and exerts a reaction force on the ribbed sealing plate and the annular part in the opposite direction. The ribbed plate structure bears the above-mentioned reaction force and serves as a support for the annular structure. The annular ribbed plate of the ribbed plate structure is a thick-walled structure with a large outer diameter instead of the thick annular part, that is, the support arm of the C-shaped clamping structure provides overall structural strength. The force application angle ε of the force F of the sealing ring can block the movement of the material of the peripheral part of the diaphragm. The position of the sealing ring is far from the heat source area and is protected by the thermal insulation method.When transporting a high-temperature fluid in a high-temperature environment, the structure of the sealing mechanism is fully supported to reduce the risk of creep and pass rigorous tests.

[0069] The innovative adjustment mechanism is that the valve stem transmission uses only three parts, compared to the five parts of the prior art. This can greatly simplify the structure and reduce manufacturing costs. It also further solves the problems of valve stem damage (Problem 4) and position locking (Problem 5). Furthermore, a solution is found for the problems of position indication (Problem 6), positioning distortion (Problem 7), diaphragm overpressure (Problem 8), and incorrect operation (Problem 9), which is applicable to both hollow valve stems and solid valve stems.

[0070] The adjustment mechanism is attached to the top of the upper valve cover, including the valve stem, an adjustment seat (e.g., an adjustment seat; hereinafter referred to as "adjustment seat"), a C-shaped retaining ring, an adjustment wheel, a displacement indicator, a positioning nut assembly, a lock nut assembly, and a safety cover.

[0071] The adjusting wheel comprises a top, an external ring surface, an internal ring surface and a hub.

[0072] The C-shaped retaining ring has an external ring surface, an inner diameter hole, an opening part, a width B, and a thickness T. Two ends of the opening part have a pair of tool holes.

[0073] The adjustment seat can either be integrated into the upper valve cover, or the adjustment seat and upper valve cover can be separate parts that must be securely secured with screws. In the best case, they are separate parts and are located concentrically above a stop post.

[0074] The assembly of the positioning nuts and the assembly of the locking nuts each consist of two nuts.

[0075] The valve stem transmission feature is described below.

[0076] The valve stem also includes a sliding part, a set screw thread and a locking thread.

[0077] The adjustment seat also includes an external ring groove, a tool opening and a sliding hole.

[0078] The adjusting wheel also contains an internal ring groove, a threaded adjustment hole and a tool holder.

[0079] The C-shaped retaining ring consists of a pair of stop posts at the two ends of the opening, each with a tool hole. The inner side of the stop post is located on the inner diameter of the hole. The radial thickness of the stop post is no greater than the depth of the tool holder of the adjustment seat.

[0080] The C-shaped retaining ring is secured in a groove formed by the external annular groove of the adjustment seat and the internal annular groove of the adjustment wheel. The outer diameter of the C-shaped retaining ring is smaller than the inner diameter of the internal annular groove. The inner diameter of the C-shaped retaining ring is larger than the inner diameter of the external annular groove. The C-shaped retaining ring is configured to axially position the adjustment wheel at an axial mounting position on the adjustment seat.

[0081] The stop post of the C-shaped retaining ring is arranged in the tool holder of the adjustment seat to ensure that the C-shaped retaining ring is not rotated with the adjusting wheel to facilitate maintenance.

[0082] The sliding part of the valve stem is coupled to the sliding hole of the adjustment seat to prevent rotation of the valve stem.

[0083] The valve stem's adjusting screw thread is coupled to the hub's adjusting threaded hole, while the adjusting wheel can be turned to move the valve stem up or down.

[0084] The threaded adjustment hole of the adjusting wheel hub, together with the C-shaped retaining ring, allows for positioning and rotation. The sliding hole of the adjustment seat prevents the valve stem from rotating. Only three parts are used to complete the function of the second type of valve stem transmission.

[0085] By securing and locking the valve stem, damage to the valve stem (Problem 4) and position locking (Problem 5) are prevented. The features of the patent are: The feature of securing and locking the valve stem to prevent damage to the valve stem (Problem 4) and position locking (Problem 5) is described below.

[0086] The displacement indicator, in the form of a gate-shaped strip, is located on the top of the adjustment wheel. The displacement indicator has a displacement space, a displacement scale, two mounting holes, and a center hole.

[0087] The internal ring groove and the external ring groove have the same groove width W and the thickness T of the C-shaped retaining ring. The groove width is W -0.0 mm >=T >= W -0.1 mm. The adjusting wheel can be smoothly rotated on the adjustment seat.

[0088] The locking thread of the valve stem protrudes through the adjustment threaded hole of the adjusting wheel and through the center hole of the displacement indicator.

[0089] At the appropriate position of the valve opening degree, the valve stem is firmly fixed to the displacement indicator by installing the lock nuts, so that the pressure wave of the pipeline carried by the valve stem is transmitted to the adjusting wheel and transmitted to the structure of the valve body through the C-shaped retaining ring, thereby preventing the adjusting screw thread of the valve stem from being damaged by the pressure wave of the pipeline.

[0090] The feature of positioning and zero return of the valve stem to avoid distortion of positioning (problem 7) and overpressure of the diaphragm (problem 8) is described below.

[0091] When the diaphragm is properly locked onto a valve seat of the valve chamber, the valve is fully closed at this time, which corresponds to the zero point of the valve opening degree. The lower nut of the positioning nut assembly is adjusted and fixed to the top of the adjusting wheel, while the positioning nut assembly is secured to the valve stem by tightening and locking the upper nut. The middle of two nuts of the positioning nut assembly serves as a reference plane for the position indicator, which corresponds to the zero point of the displacement scale. When the valve is closed, the valve stem moves downward, while the positioning nut assembly is fixed to the top of the adjusting wheel to prevent the valve stem from moving further downward and causing overpressure of the diaphragm.

[0092] The valve stem position indicator feature (Problem 6) is described below.

[0093] The displacement indicator contains a displacement scale for reading the position of the valve opening. The zeroed connecting line between the two nuts of the positioning nut assembly serves as an indicator, with the measured value corresponding to the displacement scale being the valve opening.

[0094] Another feature of the valve stem position indicator (Problem 6) is described below.

[0095] The displacement indicator has a displacement chamber, two mounting holes, a center hole, a stop screw and a mounting of lock nuts.

[0096] The displacement indicator is located on top of the pneumatic valve's upper valve cover. The valve stem locking thread protrudes through a center hole in the upper valve cover and is located within the displacement indicator's displacement space. A stop screw and locknut assembly are mounted in the center hole of the displacement indicator. The height of the stop screw end is adjusted by locking the locknut assembly. When the valve is opened, the stop screw end butts against the valve stem end. When the pneumatic valve is activated, the valve opening degree is limited to the stop screw position.

[0097] The feature to prevent incorrect operation (Problem 9) of the valve stem is described below.

[0098] The safety cover has an inner receiving chamber, a fastening side, a locking rib, and a locking hole. The fastening side of the safety cover can be mounted on the safety seat of the displacement indicator. The inner receiving chamber of the safety cover covers the entire displacement indicator, allowing the locking rib of the safety cover to function together with the locking rib of the displacement indicator. The two connected locking holes are locked with a lock that can only be opened with a key to prevent misoperation by an untrained person. Although the adjusting wheel is not covered, the valve stem and the displacement indicator are firmly locked together with the installation of the lock nuts. At this time, the adjusting wheel cannot be operated.

[0099] A fluororesin diaphragm valve structure includes a refrigerant flow channel. The refrigerant flow channel includes a valve body, a diaphragm, a seal ring, and a valve stem. The characteristics of the refrigerant flow channel are described below.

[0100] The valve stem is a hollow shaft and includes a mounting end, a hollow stem rod, and a plurality of gas guide holes. The valve body consists of an annular part having one or more cooling gas ports for introducing an external cooling gas through one or more pipe joints. The cooling gas flows through an annular cooling gas groove formed on the inside of the annular part, through a plurality of cooling gas guide holes formed on the seal ring, through a diaphragm space on the side of the diaphragm chamber that does not come into contact with liquid, and through a plurality of vent holes provided on the mounting end of the valve stem to an axle hole, after which the cooling gas is discharged from the pipe joint or axle hole.The method for collecting the vapors of the leaked liquid as a warning of leakage (Problem 10) is to connect a manifold detection system from the cooling gas hole or to connect a manifold from the rear end of the valve stem for detection, which also meets the operating temperature requirements (Problem 1). BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1A shows a detailed schematic view of the sealing mechanism of the diaphragm valve according to an embodiment of the present invention; Fig. 1B shows a schematic view of the diaphragm of the diaphragm valve according to an embodiment of the present invention; Fig. 1C shows a schematic view of the sealing ring of the diaphragm valve according to an embodiment of the present invention; Fig. 1D shows a schematic view of the sealing surface and the force introduction angle of the diaphragm valve according to an embodiment of the present invention; Fig. 1E shows a schematic view of a C-shaped tensioning device of the diaphragm valve according to an embodiment of the present invention; Fig. 2A shows a detailed schematic view of the manual adjustment device of the diaphragm valve according to an embodiment of the present invention (the adjustment mechanism is a separate element); Fig. 2B shows a cross-sectional view of the valve stem of the diaphragm valve according to an embodiment of the present invention; Fig. 2B' shows a perspective view of the valve stem of the diaphragm valve according to an embodiment of the present invention; Fig. 2C shows a cross-sectional view of the adjustment seat of the diaphragm valve according to an embodiment of the present invention; Fig. 2C' shows a perspective view of the adjustment seat of the diaphragm valve according to an embodiment of the present invention; Fig. 2D shows a cross-sectional view of the adjusting wheel of the diaphragm valve according to an embodiment of the present invention; Fig. 2D' shows a perspective view of the adjusting wheel of the diaphragm valve according to an embodiment of the present invention; Fig. 2E shows a top view of the C-shaped retaining ring of the diaphragm valve according to an embodiment of the present invention; Fig. 2E' shows a cross-sectional view of the C-shaped retaining ring of the diaphragm valve according to an embodiment of the present invention; Fig. 2F shows a schematic view of the displacement indicator of the diaphragm valve according to an embodiment of the present invention; Fig. 2G shows a schematic view of the safety cover of the diaphragm valve according to an embodiment of the present invention; Fig. 3A shows a schematic view of the manual valve 1a for increasing thermal insulation according to a first embodiment of the present invention; Fig. 3B shows a schematic view of the valve body and the annular part of the manual valve 1a according to an embodiment of the present invention; Fig. 3C shows a cross-sectional view of the upper valve cover of the manual valve 1a according to an embodiment of the present invention; Fig. 3C' shows a perspective view of the upper valve cover of the manual valve 1a according to an embodiment of the present invention; Fig. 4A shows a schematic view of the normally closed pneumatic valve 1d according to a second embodiment of the present invention; Fig. 4B shows a perspective schematic sectional view of the valve body of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 4C shows a cross-sectional view of the upper valve body of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 4C' shows a perspective view of the upper valve body of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 4D shows a cross-sectional view of the assembly of the valve stem of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 4D' shows a perspective view of the assembly of the valve stem of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 4E shows a schematic view of the sealing ring with a groove of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 5A is a schematic view showing the structure of the manual diaphragm valve 1b with the upper valve body according to a third embodiment of the present invention; Fig. 5B is a schematic view showing the structure of the manual diaphragm valve 1c having the upper valve body according to a fourth embodiment of the present invention; Fig. 5C shows a cross-sectional view of the upper valve cover and the adjustment seat of the manual diaphragm valve with the upper valve body according to an embodiment of the present invention; Fig. 5C' shows a perspective view of the upper valve cover and the adjustment seat of the manual diaphragm valve with the upper valve body according to an embodiment of the present invention; Fig. 5D shows a schematic view of the fixing ring of the manual diaphragm valve with the upper valve body according to an embodiment of the present invention; Fig. 5E shows a schematic view of the fixing screw sleeve of the manual diaphragm valve with the upper valve body according to an embodiment of the present invention; Fig. 5F shows a cross-sectional view of the valve stem assembly of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 5F' shows a perspective view of the assembly of the valve stem of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 5F'' shows another perspective view of the assembly of the valve stem of the normally closed pneumatic valve 1d according to an embodiment of the present invention; Fig. 6 is a schematic view showing that all valves of the diaphragm valve according to an embodiment of the present invention are open; Fig. 7A is a schematic view of the normally open pneumatic valve 1e for increasing thermal insulation according to a fifth embodiment of the present invention; Fig. 7B shows a schematic view of the valve body of the normally open pneumatic valve 1e for increasing thermal insulation according to an embodiment of the present invention; Fig. 7C shows a schematic view of the upper valve cover of the normally open pneumatic valve 1e for increasing thermal insulation according to an embodiment of the present invention; Fig. 7D shows an anisometric sectional view of the normally open pneumatic valve 1e for increasing thermal insulation according to an embodiment of the present invention; Fig. 8 shows a schematic view of the cooling gas flow channel of the normally open pneumatic valve 1e for increasing thermal insulation according to an embodiment of the present invention; and Fig. Figure 9 shows a schematic view of a prior art manual metal valve. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0101] The embodiments of the present invention are described below by way of example only with reference to the accompanying drawings.

[0102] The present invention shows a sealing mechanism 3 using the example of a manual diaphragm valve (see Fig. 1A) and an adjustment mechanism 7 (see Fig. 2A) of a manual valve 1a. In a first embodiment, which is shown in Fig. 3A, the manual valve 1a has an upper valve cover 6a. A ribbed sealing plate 66 is attached to the upper valve cover 6a. The ribbed sealing plate 66 serves as a force introduction element 180 and has the sealing mechanism 3a. In a second embodiment, which is shown in Fig. 4A, the adjustment mechanism 7 is modified into a limiting mechanism and applied to a normally closed pneumatic valve 1d. The normally closed pneumatic valve 1d has a sealing mechanism 3b and an upper valve body 32. The upper valve body 32 serves as a force introduction element 180A. The limiting mechanism includes a displacement indicator 76, a stop screw 70, and a safety cover 79. In a third embodiment shown in Fig. 5A, the independent adjustment mechanism 7 is applied to a normally closed pneumatic valve 1b. The normally closed pneumatic valve 1b has a sealing mechanism 3b and an upper valve body 32. The upper valve body 32 serves as a force introduction element 180A. In a fourth embodiment shown in Fig. 5B, the adjustment mechanism 7 is integrated into the upper valve cover as a normally closed pneumatic valve 1c. A fifth embodiment describes an improved mechanism for thermally insulating a normally open pneumatic valve 1e. The normally open pneumatic valve 1e has a sealing mechanism 3b and an upper valve body 32. The upper valve body 32 serves as a force introduction element 180A. A sixth embodiment describes a cooling gas flow channel 16. The following embodiments are described in detail.

[0103] All descriptions are in the Fig. 1A, Fig. 1B, Fig. 1C, Fig. 1D, Fig. 1E, Fig. 2A, Fig. 2B, Fig. 2B', Fig. 2C, Fig. 2C', Fig. 2D, Fig. 2D', Fig. 2E, Fig. 2E', Fig. 2F, Fig. 2G, Fig. 3A, Fig. 3B, Fig. 3C, Fig. 3C', Fig. 4A, Fig. 4B, Fig. 4C, Fig. 4C', Fig. 4D, Fig. 4D', Fig. 4E, Fig. 5A, Fig. 5B, Fig. 5C, Fig. 5C', Fig. 5D, Fig. 5E, Fig. 5F, Fig. 5F', Fig. 5F'', Fig. 6, Fig. 7A, Fig. 7B, Fig. 7C, Fig. 7D, Fig. 8 and Fig. 9 to find.

[0104] In the following, the basic mode and the first embodiment will be considered as the main example, with various embodiments of the second embodiment, the third embodiment, and the fourth embodiment being illustrated. Different reference numerals represent adaptations of the structure. For example, the ribbed plate structure 244a / 244b / 244c means that there are three embodiments of a ribbed plate structure 244, designated by the three reference numerals 244a, 244b, 244c, all of which achieve the same effect.

[0105] For a sealing mechanism 3a / 3b, the basic mode and the first embodiment are used below as a main example.

[0106] As in Fig. As shown in FIG. 1A, the sealing mechanism 3a / 3b consists of a diaphragm 30, a sealing ring 31, a sealing surface (e.g., a clamping surface; hereinafter referred to as "sealing surface") 327 / 662, a sealing surface 240, an annular portion 24a / 24b / 24c, and a ribbed plate assembly 244a / 244b / 244c. The sealing mechanism 3a / 3b is based on a valve body 2a / 2b / 2c as the main structure. The valve body 2a / 2b / 2c has an inlet 21, an outlet 22, a valve chamber 23, the annular portion 24a / 24b / 24c, and a square portion 25a / 25b.

[0107] The annular portion 24a / 24b / 24c is a cup-shaped structure with an opening, is sealed with an upper valve cover 6a / 6b / 6c, and includes the sealing surface 240, an external annular surface 245, a minimum diameter portion 241, the valve chamber 23, and the ribbed plate assembly 244a / 244b / 244c. The sealing surface 240 is formed on the outer periphery of the valve chamber 23. A square portion 25a / 25b is provided below the valve chamber 23 and coupled to the valve chamber 23 to form a support. The ribbed plate assembly 244a / 244b / 244c is provided on the external annular surface 245 of the annular portion 24a / 24b / 24c. The annular part 24a / 24b / 24c also has one or more cooling gas holes 162 and a cooling gas annular groove 163.

[0108] The upper valve cover 6a / 6b / 6c has an inner receiving chamber 61, an external annular surface 62, a top surface 63, a center hole 64, and a ribbed sealing plate 66. The sealing surface 662 / 67 is derived from the force introduction element 180, parts, or structures of other valve structures. The force introduction element 180 is, for example, the ribbed sealing plate 66 or an upper valve body 32. These parts or structures are firmly secured to the annular part 24a / 24b / 24c.

[0109] The ribbed plate assembly 244a / 244b / 244c is an annular lattice structure with a plurality of horizontal openings. One side of the ribbed plate assembly 244a / 244b / 244c is axially fixed to the square portion 25a / 25b, while the distribution position includes the minimum diameter region 241. The other side of the ribbed plate assembly 244a / 244b / 244c in the axial direction includes the seal ring 31.

[0110] The ribbed plate assembly 244a / 244b / 244c consists of one or more spaced-apart annular ribbed plates and a plurality of spaced-apart vertical ribbed plates. The plurality of vertical ribbed plates are axially attached to all of the annular ribbed plates by the square portion 25a / 25b.

[0111] The Fig. Figure 1B shows that the diaphragm 30 consists of a peripheral part 301, an elastic part 302, and a central part 303. The peripheral part 301 has upper and lower side surfaces. The upper side surface is defined as a force-absorbing surface (e.g., a force-absorbing surface, hereinafter referred to as a "force-absorbing surface") 304, and the lower side surface is defined as a mating surface 305.

[0112] The Fig. Figure 1C shows that the sealing ring 31 is an annular structure with an approximately rectangular cross-section and has two ends defined as a force-absorbing end 314 and a tightening end 315. The tightening end 315 is an obtuse angle β and, in the best embodiment, is 110°≤β≤150°.

[0113] The Fig. 1D shows that the peripheral portion 301 is subjected to a force and tension to generate displacement as the diaphragm 30 expands and deforms under the pressure of the conduit. The peripheral portion 301 has a wedge-shaped cross-section with a greater thickness on its outer side and a smaller thickness on its inner side, which are attached to the elastic portion. The peripheral portion 301 has upper and lower side surfaces. The upper side surface is defined as the force-receiving surface 304, and the lower side surface is defined as the mating surface 305. The mating surface 305 and the force-receiving surface 304 are not flat or conical surfaces. The mating surface 305 is attached to the sealing surface 240 of the annular portion 24a / 24b / 24c. The force-receiving surface 304 is tightly pressed by the tightening end 315 of the sealing ring 31. The sealing surface 240 may be a conical or flat surface. Fig. 1D shows that the sealing surface 662 / 327 serves as a force introduction element 180A, wherein the force introduction element 180A is the upper valve body 32

[0114] The Fig. 1A and Fig. 2B shows that the valve stem 4a / 4b / 4c is a hollow shaft with a mounting end 41 and a stem rod 42. The mounting end 41 has a plurality of gas guide holes 413 and a screw hole 411. The mounting end 41 can be mounted with a screw 414 and a nut 412 to securely fasten the diaphragm 30. The valve stem 4a / 4b / 4c and the diaphragm 30 can rotate relative to each other. The sealing ring 31 is mounted on the peripheral part 301 of the diaphragm. The diaphragm 30 is mounted, together with the axle, on the sealing surface 240 of the annular part 24a / 24b / 24c.

[0115] The Fig. 1D, the sealing surface 327 / 662 and the force-absorbing end 314 are pushed in the locked state while a clamping force F is exerted on the force-absorbing end 314, so that the tightening end 315 is bent at an obtuse angle β (see Fig. 1C) can be attached and tightened to the peripheral part 301. When the sealing surface 240 is tightened by the force F, it is supported by the ribbed plate structure 244a / 244b / 244c of the annular part 24a / 24b / 24c and carried by the square part 25a / 25b and the side wall of the flow channel of the valve chamber 23. The clamping force F has a force application angle ε with the normal N of the peripheral part 301, and the force application angle ε is in the range 0°<ε≤15°. The sealing ring 31 is deformed by the force and exerts a force on the peripheral part 301 of the diaphragm 30. At the same time, the force is also exerted on the sealing surface 240 to which the peripheral part 301 is attached. The structure of the minimum diameter area 241 and the square part 25a / 25b below the sealing surface 240 also forms a support.The minimum diameter region 241 has a heat transfer restriction region to reduce heat transfer.

[0116] The Fig. 1E shows that the annular part 24a / 24b / 24c with the sealing surface 327 / 662 is attached to the sealing surface 240 to form a C-shaped clamping structure 18. A clamping part 181 of the C-shaped clamping structure 18 consists of the force introduction element 180A. The Fig. 1E shows that the force introduction element 180A is the upper valve body 32, with the force introduction element 180A being fixedly attached to the annular portion 24a / 24b / 24c. A support arm 182 of the C-shaped clamping structure 18 provides overall structural strength to the annular portion 24a / 24b / 24c and the ribbed plate assembly 244a / 244b / 244c. A substructure 183 of the C-shaped clamping structure 18 is the sealing surface 240, which is supported by the minimum diameter region 241, the sidewall of the flow channel of the valve chamber 23, and the ribbed plate assembly 244a / 244b / 244c. The sealing surface 327 / 662 is moved downward by firmly snapping into place so that the sealing ring 31 and the diaphragm 30 are clamped to the sealing surface 327 / 662 and the sealing surface 240 to prevent leakage.

[0117] The Fig. 2A shows that an adjustment mechanism 7 is used in various embodiments. Different reference numerals indicate different structural adaptations with which the same effect of adjusting the degree of valve opening is achieved. The adjustment mechanism 7 can be screwed to the top surface 63 of an upper valve cover 6a / 6b / 6c and includes the valve stem 4a / 4b / 4c / 4d, an adjustment seat 71, an adjusting wheel 74, a displacement indicator 76, a positioning nut assembly 77, a lock nut assembly 78, and a safety cover 79. The positioning nut assembly 77 and the lock nut assembly 78 each consist of two nuts.

[0118] The Fig. 2B and Fig. 2B' show the valve stem 4a / 4b / 4c / 4d. The valve stem 4a further comprises a sliding part 45, a set screw thread 46, and a locking thread 47. The sliding part 45 is an axle with two parallel cutouts.

[0119] The Fig. 2C and Fig. 2C' show that the adjustment seat 71 has a shoulder 711, a neck portion 712, an interior space 713, an external annular groove (e.g., an external groove; hereinafter referred to as "external annular groove") 716, a tool receptacle 717, and a sliding hole 718. The adjustment seat 71 may be integrated into the upper valve cover 6a / 6b / 6c, or the adjustment seat 71 and the upper valve cover 6a / 6b / 6c may be individual parts that are firmly secured with screws. In the best embodiment, they are individual parts. The adjustment seat 71 includes a stop post 719 that is provided with a positioning hole 69 (see Fig. 2A) of the upper valve cover 6a / 6b / 6c to ensure the concentric positioning of the valve stem 4a / 4b / 4c. The adjusting seat 71 has a plurality of screw holes (not shown) for being firmly connected to a plurality of threaded holes (not shown) of the upper valve cover.

[0120] The Fig. 2D and Fig. 2D' show that the adjusting wheel 74 has a top surface 741, an external annular surface 742, an internal annular surface 743, an internal annular groove 744, a hub 745, a threaded adjustment hole 746 and a tool holder 747.

[0121] The Fig. 2E and Fig. 2E' shows that a C-shaped retaining ring 75 has an external ring 751, an inner diameter hole 752, an opening portion 753, two tool holes 754, a width B, and a thickness T. The two ends of the opening portion 753 have the tool holes 754. The inside of a stop post 755 is located on the inner diameter of the inner diameter hole 752. The radial thickness of the stop post 755 is not greater than the depth of the tool holder 717 of the adjustment seat 71.

[0122] The Fig. Figure 2F shows that the displacement indicator 76 is provided in the form of a gate-shaped strip on the upper surface 741 of the adjusting wheel 74. The displacement indicator 76 has a displacement space 761, a displacement scale 762, two mounting holes 763, and a center hole 764.

[0123] The Fig. 2F and Fig. 2G show that the adjustment mechanism 7 can be installed with the safety cover 79. The safety cover 79 has an internal receiving chamber 791, a mounting side 792, a securing rib 793, and a locking hole 794. The displacement indicator 76 also includes a safety seat 765, a securing rib 766, and a locking hole 767. The mounting side 792 of the safety cover 79 can be attached to the safety seat 765, which has a notch 768 of the displacement indicator 76.The inner receiving chamber 791 of the safety cover 79 covers the entire displacement indicator 76, allowing the locking rib 793 of the safety cover 79 to function together with the locking rib 766 of the displacement indicator 76. The two interconnected locking holes 767, 794 are locked with a lock that can only be opened with a key to prevent misoperation by an untrained person. Although the adjusting wheel 74 is not covered, the valve stem 4a and the displacement indicator 76 are firmly secured to each other by installing the lock nuts 8 (see ). Fig. 2A). At this point, the adjusting wheel 74 cannot be operated.

[0124] The Fig. 2A shows that the sliding part 45 of the valve stem 4a / 4b / 4c / 4d is coupled to the sliding hole 718 of the adjustment seat 71 to prevent the valve stem 4a / 4b / 4c / 4d from rotating. The adjusting screw thread 46 of the valve stem 4a / 4b / 4c / 4d is coupled to the adjusting threaded hole 746 of the hub 745, while the adjusting wheel 74 can be rotated to move the valve stem 4a / 4b / 4c / 4d up and down. The locking thread 47 of the valve stem 4a / 4b / 4c / 4d protrudes through the adjusting threaded hole 746 of the adjusting wheel 74 and the center hole 764 of the displacement indicator 76.

[0125] The Fig. 1A and Fig. 2A show that the valve is fully closed, which corresponds to the zero point of the valve opening degree, when the diaphragm 30 is properly secured on the valve seat 231 of the valve chamber 23. The lower nut of the positioning nut assembly 77 is adjusted and fastened to the top surface 741 of the adjusting wheel 74, and the positioning nut assembly 77 is secured to the valve stem 4a / 4b / 4c / by tightening the upper nut. The middle of the two nuts of the positioning nut assembly 77 serves as a reference plane for the position indicator, which corresponds to the zero point of the displacement scale 762 of the displacement indicator 76. When the valve is closed, the valve stem 4a / 4b / 4c / 4d is moved downwards, with the assembly of the positioning nuts 77 fixed to the top 741 of the adjusting wheel 74 to prevent the valve stem 4a / 4b / 4c / 4d from being moved further downwards and exerting excess pressure on the diaphragm 30.

[0126] In the position of a suitable opening degree of the valve, the valve stem 4a / 4b / 4c / 4d is firmly secured on the displacement indicator 76 by installing the lock nuts 78, so that the pressure wave of the pipeline carried by the valve stem 4a / 4b / 4c / 4d is transmitted to the adjusting wheel 74 and through the C-shaped retaining ring to the structure of the valve body, thereby preventing the adjusting screw thread 46 of the valve stem 4a / 4b / 4c / 4d from being damaged by the pressure wave of the pipeline.

[0127] The displacement indicator 76 contains the displacement scale 762 for reading the position of the valve opening degree. The zeroed connecting line between the two nuts of the positioning nut assembly 77 is used as an indicator, and the measured value corresponding to the displacement scale 762 is the valve opening degree.

[0128] The C-shaped retaining ring 75 is secured in a groove composed of the external annular groove 716 of the adjustment seat 71 and the internal annular groove 744 of the adjustment wheel 74. The outer diameter of the C-shaped retaining ring 75 is smaller than the inner diameter of the internal annular groove 744. The inner diameter of the C-shaped retaining ring 75 is larger than the inner diameter of the external annular groove 716. The C-shaped retaining ring 75 is configured to position the adjustment wheel 74 in an axially secured position on the adjustment seat 71.

[0129] The internal annular groove 744 and the external annular groove 716 have the same groove width W and are slidably secured to the thickness T of the C-shaped retaining ring 75. The groove width is W -0.0 mm >=T >=W -0.1 mm. The adjusting wheel 74 can be smoothly rotated on the adjusting seat 71, and the pressure wave of the line is transmitted to the annular part 24a / 24b / 24c via the valve stem 4a / 4b / 4c / 4d.

[0130] The stop post 755 of the C-shaped retaining ring 75 is positioned in the tool holder 717 of the adjustment seat 71 to ensure that the C-shaped retaining ring 75 is not rotated with the adjusting wheel 74 to facilitate maintenance (see Fig. 2E and Fig. 2E').

[0131] The threaded adjustment hole 746 of the hub 745 of the adjusting wheel 74 allows positioning and rotation with the C-shaped retaining ring 75. The sliding hole 718 of the adjusting seat 71 stops the rotation of the valve stem 4a / 4b / 4c / 4d. Only three parts are used to complete the function of the second type of valve stem transmission.

[0132] The Fig. Figure 3A shows that in the first embodiment, the manual valve 1a consists of a sealing mechanism 3a, an adjustment mechanism 7, and a valve part 10a. The sealing mechanism 3a is described in the first embodiment. The valve part 10a consists of a valve body 2a, an upper valve cover 6a, the diaphragm 30, the sealing ring 31, and a valve stem 4a.

[0133] The Fig. 3A and Fig. 3B shows that the valve body 2a includes the inlet 21, the outlet 22, the valve chamber 23, an annular portion 24a, and a square portion 25a. The outlet 22, the inlet 21, and the valve chamber 23 form the flow space for conveying the fluid, which serves as the heat source region 15. Both the annular portion 24a and the square portion 25a include a heat transfer restriction structure 151. The annular portion 24a further includes an external screw thread 243 and an internal annular surface 247. The valve stem 4a extends through a center hole 64 of the stem boss portion 68 of the upper valve cover 6a, so that the upper valve cover 6a can be tightly screwed to the external screw thread 243 of the annular portion 24a.

[0134] The Fig. 3A, Fig. 3B and Fig. 3C show that the upper valve cover 6a further includes a stem boss portion 68 and a center hole 64. The upper valve cover 6a further includes the axially annular ribbed sealing plate 66 located between the stem boss portion 68 and the internal screw thread 65, a thread groove (e.g., a thread groove; hereinafter referred to as "thread groove") 663 located between the annular ribbed sealing plate 66 and the internal screw thread 65, and a stem boss groove 664 located between the stem boss portion 68 and the annular ribbed sealing plate 66. The lower end of the ribbed annular sealing plate 66 has an annular clamping groove 661. The opening of the groove is formed opposite to the thread groove 663 and directed downward. A clamping surface 662 is formed at the upper bottom of the clamping groove 661. The sealing ring 31 is fastened in the annular clamping groove 661.A plurality of radial ribs 683 are formed between the ribbed annular seal plate 66 and the stem boss portion 68 to enhance the strength of the ribbed annular seal plates 66 and to insulate the heat transmitted from the valve stem 4a. The external annular surface of the ribbed annular seal plate 66 has a plurality of convex longitudinal ribs 665. The plurality of convex longitudinal ribs 665 are adjacent to the internal annular surface 247 of the annular portion 24a to provide structural strength and to insulate the heat transmitted from the peripheral portion 301 of the diaphragm 30.

[0135] The Fig. 3A shows that the structural support of the sealing mechanism 3a consists of the annular part 24a, the diaphragm 30, the seal ring 31, the ribbed plate assembly 244a, and the upper valve cover 6a. The other side of the ribbed plate assembly 244a in the axial direction is screwed to the external screw thread 243. When the upper valve cover 6a is tightly closed with the annular part, the structure of the annular part 24a is embedded in the thread groove 663.

[0136] The Fig. 3A shows that the adjustment mechanism 7 is installed on the top surface 63 of the upper valve cover 6a and coupled to the positioning hole 69 of the upper valve cover 6a via the stop post 719 of the adjustment seat 71. The adjustment mechanism 7 consists of the valve stem 4a, the adjustment seat 71, the adjusting wheel 74, the displacement indicator 76, the positioning nut assembly 77, the lock nut assembly 78, and the safety cover 79.

[0137] The Fig. 4A, Fig. 4D and Fig. 4D' show that, in the second embodiment, the displacement indicator 76 is applied to a normally closed pneumatic valve 1d having a sealing mechanism 3b. The sealing mechanism 3b will be described with reference to the second and third embodiments, wherein the opening degree is limited by the displacement indicator 76.

[0138] The normally closed pneumatic valve 1d consists of a valve part 10b, a drive cylinder 10d, the sealing mechanism 3b, and the displacement indicator 76. The valve part 10b consists of a valve body 2b, the diaphragm 30, the sealing ring 31, the upper valve body 32, and the valve stem 4b. The drive cylinder 10d is a cylinder chamber 17 that is hermetically sealed from the upper valve body 32 to the upper valve cover 6b. The piston 44 of the valve stem 4b divides the chamber into a gas chamber 171 and a spring chamber 172. A spring set is installed in the upper spring chamber 172 to keep the diaphragm 30 normally closed. The lower gas chamber 171 is pressurized with high-pressure air to open the diaphragm 30. The opening degree of the valve can be adjusted with the adjustment mechanism 7. The upper valve cover 6b also has an internal screw thread 65, a displacement height H (see Fig. 5A) and a positioning hole 69. In this embodiment, the force introduction element 180A is the upper valve body 32.

[0139] The Fig. Figure 4B shows that the valve body 2b includes the inlet 21, the outlet 22, the valve chamber 23, an annular portion 24b, and a square portion 25a. The annular portion 24b further includes an internal screw thread 242, an external screw thread 243, the ribbed plate structure 244b, and an internal annular surface 247.

[0140] The Fig. 4C and Fig. 4C' show that the upper valve body 32 has a locking thread 321, a clamping groove 322, a stem hole 323, one or more annular grooves (e.g., annular grooves; hereinafter referred to as "annular grooves") 324, a plurality of ribbed groove plates 325, a diaphragm chamber 326, and the sealing surface 327.

[0141] The Fig. 4D and Fig. 4D' show that the valve stem 4b is a hollow stem including the attachment end 41, the hollow stem rod 42, the plurality of gas guide holes 413, and the piston 44. The piston 44 is located at the center of the valve stem 4b. The piston 44 is shaped like a disc and includes a plurality of vertical ribbed plates 442 and one or more annular ribbed plates 441. The annular ribbed plate 441 is inserted into the annular groove 324 of the upper valve body 32. The vertical ribbed plates 442 are configured to exert a torsional force to securely attach the upper valve body 32.

[0142] The Fig. 4D, Fig. 4D' and Fig. 4E shows that the sealing ring 31 is secured in the tension groove 322 of the upper valve body 32. The force-absorbing end 314 is secured to the sealing surface 327, while an O-ring-shaped groove 313 is formed on the external ring side of the force-absorbing end 314. The tightening end 315 is secured to the force-absorbing surface 304.

[0143] When the locking thread 321 of the upper valve body 32 is tightly screwed to the internal screw thread 242 of the annular part 24b (see Fig. 4A), a force F is exerted on the force-absorbing end 314 by the sealing surface 327 of the annular groove 324, so that the tightening end 315 is pressed against the force-absorbing surface 304 at an obtuse angle β.

[0144] The Fig. 4A shows that the sealing mechanism 3b consists of the annular part 24b, the diaphragm 30, the sealing ring 31, the ribbed plate structure 244b, and the upper valve body 32. When the upper valve body 32 is tightly screwed to the internal screw thread 242 and pressed against the sealing ring 31, the sealing mechanism 3b is supported by the external ring side of the sealing surface 240 and the ribbed plate structure 244b. The underside of the sealing surface 240 is supported by the square part 25a and the side wall of the flow channel 232 of the valve chamber 23 and also includes the structure near the minimum diameter region 241.

[0145] The sealing mechanism 3b and the external screw thread are arranged on the external annular surface 245 of the annular part 24b, while the sealing mechanism 3b is arranged below the external screw thread 243. The axial distribution position of the ribbed plate structure 244b includes the minimum diameter range 241 and a plurality of screw threads of the internal screw thread 242. The other side of the ribbed plate structure 244b in the axial direction is fixed to the external screw thread 243 to improve the structural strength and the heat dissipation effect of the sealing mechanism 3b. The internal screw thread 242 and the external screw thread 243 of the annular part 24b have a plurality of threads that overlap in the axial position, that is, the axial position distribution of the internal screw thread 242 is covered by the axial length of the external screw thread 243 and the ribbed plate structure 244.When the upper valve cover 6b is tightly screwed to the external screw thread 243 of the annular part 24b, the upper valve body 32 is additionally supported by the upper valve cover 6b.

[0146] The Fig. 4A shows that the displacement indicator 76 is mounted on the top surface 63 of the upper valve cover 6b. Two stop posts 769 are provided on the bottom of the displacement indicator 76, which are coupled to the positioning hole 69 of the upper valve cover 6b. The displacement indicator 76 also consists of a stop screw 70, the assembly of the lock nuts 78, and the safety cover 79.

[0147] The stop screw 70 is first installed with the lock nut assembly 78 and then protrudes through the center hole 764 of the displacement indicator 76. The lock nut assembly 78 is installed from the end of the stop screw until the end of the stop screw 70 reaches a required height. This height also corresponds to the height of the valve stem 4b to be moved upward. At this time, the stop screw 70 is firmly screwed to the lock nut assembly 78. When the high-pressure gas is introduced into the drive cylinder 10d, the end of the valve stem 4b is blocked by the stop screw 70. The safety cover 79 is configured to protect the displacement indicator 76.

[0148] The Fig. 5A shows that the third embodiment uses the manual valve 1b instead of the valve in the second embodiment. The sealing mechanism 3a is described in the second and third embodiments. The manual valve 1b no longer has the drive cylinder 10d, but still has the sealing mechanism 3b and the adjustment mechanism 7. The manual valve 1b consists of the valve part 10b, the sealing mechanism 3b, and the adjustment mechanism 7. The valve part 10b consists of the valve body 2b, the valve stem 4c, the upper valve body 32, the diaphragm 30, the sealing ring 31, and the upper valve cover 6b. The upper valve cover 6b has a displacement height H. In this embodiment, the force introduction element 180A is the upper valve body 32.

[0149] The adjustment mechanism 7 is mounted on the top surface 63 of the upper valve cover 6b. The shoulder 711 of the adjustment seat 71 has several round holes to facilitate the fastening of the adjustment mechanism 7. After the sealing mechanism 3b is firmly secured, the valve stem 4c is no longer rotated.

[0150] The Fig. 5F shows that it is not necessary for the valve stem 4c to have the sliding part 45 and the adjusting seat 71 to have the sliding hole 718. The valve stem 4c can be inserted through the center hole 64 of the valve cover 6b to close the annular part 24b. Rotation is not affected by the valve stem 4c and the center hole 64. The stop post 719 of the adjusting seat 71 is coupled to the positioning hole 69 of the upper valve cover 6b, so that the adjusting mechanism 7 is mounted on the valve stem 4c. When the adjusting wheel 74 is rotated to open the diaphragm, the valve stem 4c is rotated upward until the vertical ribbed plate 442 on the top of the piston 44 completes its stroke H and contacts the top of the inner receiving chamber 61 of the upper valve cover 6b.

[0151] The Fig. 5B shows that in the fourth embodiment, the manual valve 1b is used instead of the valve in the third embodiment. The adjustment seat 71 of the adjustment mechanism 7 of the manual valve 1c is integrated into the upper valve cover 6b, with the other components of the sealing mechanism 3b still being used. Since the adjustment seat 71 is integrated into the upper valve cover 6b in this embodiment, the valve stem 4d cannot be inserted through the center hole 64 of the upper valve cover 6b and then through the sliding hole 718 after assembling the valve part 10b with the sealing mechanism 3b. Since this causes the valve stem 4d to rotate and the annular ribbed plate 441 of the piston 44 (see Fig. 5F, Fig. 5F and Fig. 5F'') to rotate the fixed upper valve body 32, the rotation of the rotating shaft is thereby impaired. In this embodiment, the force introduction element 180A is the upper valve body 32.

[0152] The Fig. 5C and Fig. 5C' show that the solution consists in installing a fixing seat 714 and a locking thread (e.g. a fixing screw hole; hereinafter referred to as “locking thread”) 715 in an interior 713 of an adjustment seat 71, wherein a fixing ring 72 and a fixing screw sleeve 73 (see Fig. 5B) are provided instead of the sliding hole 718 of the adjustment seat 71.

[0153] The Fig. Figure 5D shows that the fixing ring 72 has a flange 721, an external ring surface 722 and an elongated hole 723.

[0154] The Fig. 5E shows that the fixing screw sleeve 73 has an external screw thread 731, a center hole 732 and a twisting part (e.g., a clamping part; hereinafter referred to as “twisting part”) 733.

[0155] The Fig. 5B, Fig. 5C, Fig. 5C', Fig. 5D and Fig. 5E shows that one end of the valve stem 4d passes through the center hole 64 of the upper valve cover 6b, the upper valve cover 6b can be firmly screwed to the external screw thread 243 of the annular part 24b, after which the fixing ring 72 can be attached to the fixing seat 714. The outer diameter of the flange 721 of the fixing ring 72 is larger than the center hole 64. The external annular surface 722 is slidably connected to the center hole 64 to achieve an axis positioning function. The elongated hole 723 cooperates with the sliding part 45 of the valve stem 4d. After the fixing screw sleeve 73 is firmly secured in the locking thread 715 via the rotating part 733, the fixing ring 72 is fixed, and the valve stem 4d can no longer be rotated. The C-shaped retaining ring 75 is then inserted into the external annular groove 716 using a tool, after which the adjusting wheel 74 is inserted.

[0156] The Fig. 6 shows a comparison view of the fully open / closed valve of the manual valve 1c of the fourth embodiment.

[0157] The Fig. 7A shows that the fifth embodiment uses the normally open pneumatic valve 1e instead of the valve in the second embodiment. The sealing mechanism 3b is described in the second and fourth embodiments, illustrating the structure for further improving heat dissipation. The normally open pneumatic valve 1e consists of a drive cylinder 10d, a valve part 10c, and a sealing mechanism 3b. The drive cylinder 10d has a structure for improving heat dissipation. The drive cylinder 10d and the valve part 10c are hermetically secured with four metal screws that protrude through four locking posts 13.

[0158] The Fig. Figure 7D shows that the drive cylinder 10d is a cylinder chamber 17, which is hermetically sealed from the upper valve body 32 to the upper valve cover 6c. The piston 44 of the valve stem 4b divides the chamber into a gas chamber 171 and a spring chamber 172. A spring set is installed in the upper spring chamber 172 to keep the diaphragm 30 normally open. To close the diaphragm 30, high-pressure air is introduced into the lower gas chamber 171.

[0159] The valve part 10c consists of a valve body 2c, the upper valve body 32, a membrane 30, the valve stem 4b and a sealing ring 31.

[0160] The Fig. 7B and Fig. 7D show that the valve body 2c further includes an annular portion 24c and a square portion 25b. The annular portion 24c further includes an internal screw thread 242, a ribbed plate assembly 244c, a surface seal 246, four locking posts 13, and a gas lock 14. The annular portion 24c and the upper valve cover 6c are tightly screwed together with metal screws that protrude through the locking posts 13. The surface seal 246 and the surface seal 67 are tightly sealed. The locking post 13 of the upper valve cover 6c has a screw hole. A metal nut is provided internally in the locking post 13 of the annular portion 24c. For tight sealing, a screw protrudes through the screw hole and secures the nut.

[0161] The Fig. 7C and Fig. 7D show that the upper valve cover 6c further includes a plurality of annular ribbed plates 621, a plurality of locking posts 13, an internal annular surface 611, and a plurality of gas locks 14. The internal annular surface 611 serves as a sealing sliding surface of the piston 44. The inside of the upper valve cover 6c is defined as the gas space 171. The annular ribbed plate 621 axially distributes and encompasses the axial length of the upper valve cover 6c, also has the axial length of the internal annular surface 611, and fixes the locking posts 13 and the gas locks 14. When high reliability is required in a high-temperature environment, a plurality of annular ribbed plates 621 of the upper valve cover 6c are replaced with the ribbed plate assembly 244c (not shown) to ensure the structural strength of the cylinder space 17.

[0162] The Fig. 7D shows that the four corners of the upper valve cover 6c and the annular portion 24c each have the locking posts 13 mounted above the minimum diameter portion of the annular portion 24c and spaced from and disposed above the square portion 25b, that is, above the heat source portion 15 and the minimum diameter portion 24b, to prevent the thick structure of the locking post 13 from becoming a large heat transfer surface, causing thermal insulation failure. A gasket is provided between the surface seal 246 and the surface seal 67 to ensure that the metal bolt does not corrode.

[0163] The upper valve cover 6c has an inlet pipe connected for a high-pressure propellant gas. The propellant gas flows through the gas space 171. The upper valve cover 6c has an inlet pipe connected for a cooling gas, which is connected to the annular part 24c via the gas barrier. For internal cooling, the annular part 24c has a cooling gas opening. The cooling gas hole is formed above the minimum diameter region 241 and spaced from and above the square part 25b, that is, it is formed above the heat transfer restriction region and the minimum diameter region 241 to prevent the thick structure from becoming a large heat transfer area, causing thermal insulation failure. Both the gas barrier 14 and the cooling gas hole 162 have an O-ring to ensure airtightness.

[0164] The Fig. 7D shows that the sealing mechanism 3b includes the annular portion 24c, the diaphragm 30, the seal ring 31, and the upper valve body 32, and is arranged above the heat transfer restriction area. The finned plate assembly 244c of the sealing mechanism 3b includes more than one annular finned plate and a plurality of vertical finned plates. The plurality of vertical finned plates are axially fixed to all the annular finned plates via the square portion. The axial distribution position of the finned plate assembly 244c includes the minimum diameter portion 241 and the external annular surface 245, as well as the axial length of the internal screw thread 242 in the axial position, which also fixes the barrier posts 13 and the gas barriers 14.When the upper valve cover 6c is tightly closed, the structural rigidity and heat dissipation effect of the cylinder chamber 17 are increased by the annular ribbed plate 621 and the sealing mechanism 3b. Especially when the ambient temperature is 100°C, the heat dissipation area is greatly increased. In this embodiment, the force introduction element 180A is the upper valve body 32.

[0165] The Fig.8 shows the cooling gas flow channel 16 in a sixth embodiment. The external annular surface of the annular part 24 has one or more cooling gas holes 162 for introducing an external cooling gas through a pipe connection. The pipe connection is located above the minimum diameter region 241. The cooling gas flows through a cooling gas annular groove 163 provided on the inner side of the annular part 24, through a plurality of cooling gas guide holes 164 provided on the sealing ring 31, through a diaphragm space 165 on the side of the diaphragm chamber 326 that does not come into contact with liquid, and through a plurality of vent holes 166 formed on the attachment end 41 of the valve stem 4b, to the stem hole 167, after which the cooling gas exits from the pipe connection or from the outlet of the stem. The annular part 24 has a cooling gas hole for connecting the external cooling gas.The cooling gas hole is formed above the minimum diameter region 241 and spaced from and above the square part 25, that is, above the heat transfer restriction region and the heat source region 15, to prevent the thick structure from becoming a large heat transfer region and causing thermal insulation failure. The method for capturing the vapor of the leaked liquid for leakage warning (Problem 10) is to connect a manifold detection system from the cooling gas hole 162 or to connect a manifold from the end portion of the valve stem 4 through the stem hole 167 for detection. In this embodiment, the force introduction member 180A is the upper valve body 32.

Claims

[1] A structure of the manual diaphragm valve made of fluororesin, comprising an adjustment mechanism (7) configured to manually adjust an opening degree of the valve; the adjustment mechanism (7) is mounted on an upper valve cover (6a); the upper valve cover (6a) has a center hole (64) and one or more positioning holes (69); characterized by , that: the adjustment mechanism (7) consists of a valve stem (4a), an adjustment seat (71), a C-shaped retaining ring (75), an adjusting wheel (74), a displacement indicator (76), an assembly of the positioning nuts (77) and an assembly of the locking nuts (78); the valve stem (4a) is a hollow stem and has a mounting end (41), a stem rod (42), a plurality of gas guide holes (413), a sliding part (45), a set screw thread (46), and a locking thread (47); the sliding part (45) is an axle with a pair of parallel cutouts; the adjustment seat (71) has a shoulder (711), a neck portion (712), an interior space (713), an external annular groove (716), a tool holder (717), and a stop post (719); the stop post (719) is coupled to the positioning hole (69) to hold the valve stem (4a) concentrically; the C-shaped retaining ring (75) has an external ring surface, an inner diameter hole (752), an opening part (753), two tool holes (754), a width B, and a thickness T; each assembly of the positioning nuts (77) and assembly of the locking nuts (78) consists of two nuts; the adjusting wheel (74) has a top surface (741), an external annular surface (742), an internal annular surface (743), an internal annular groove (744), a hub (745), an adjustment threaded hole (746) and a tool holder (747); the displacement indicator (76) in the form of a gate-shaped strip has a displacement space (761), a displacement scale (762), two mounting holes (763) and a center hole (764); the C-shaped retaining ring (75) is fully opened in the internal annular groove (744) and in the external annular groove (716); the internal annular groove (744) and the external annular groove (716) have an equal groove width W and are slidably attached to the thickness T of the C-shaped retaining ring (75); wherein the adjusting wheel (74) can be smoothly rotated on the adjusting seat (71); the sliding hole (718) is coupled to the sliding part (45) of the valve stem (4a), while the adjusting screw thread (46) of the valve stem (4a) is coupled to the adjusting thread hole (746) of the adjusting wheel (74). [2] The structure of the fluororesin manual diaphragm valve according to claim 1, wherein the C-shaped retaining ring (75) is fixed with a tool that protrudes through the tool holder (717) and the two tool holes (754), after which the adjusting wheel (74) is mounted on the adjusting seat (71); the inner diameter of the C-shaped retaining ring (75) is smaller than the outer diameter of the external annular groove (716), while the outer diameter of the C-shaped retaining ring (75) is smaller than the inner diameter of the internal annular groove (744). [3] The structure of the manual diaphragm valve made of fluororesin according to claim 1, wherein the groove width W -0.0 mm>=T>= W -0.1 mm; the force of the pressure wave is transmitted directly to the adjusting wheel (74) and to the structure of the valve body via the C-shaped retaining ring (75) when the valve stem (4a) is subjected to a pressure wave. [4] The structure of the fluororesin manual diaphragm valve according to claim 1, wherein the displacement indicator (76) is mounted on the top surface (741) of the adjusting wheel (74); the valve stem (4a) protrudes through the center hole (764) of the displacement indicator (76); the assembly of the lock nuts (78) is mounted; the valve stem (4a) is firmly secured to the displacement indicator (76) with the assembly of the lock nuts (78); the assembly of the positioning nuts (77) is mounted on the locking thread (47); the lower nut of the assembly of the positioning nuts (77) is fixed to the top surface (741) of the adjusting wheel (74) when the valve is closed, while the assembly of the positioning nuts (77) is fixed to the valve stem (4a) by firmly tightening the upper nut; a center line of two nuts of the mounting of the positioning nuts (77) serves as a reference for the position indicator, which corresponds to a zero point of the displacement scale (762);to readjust the degree of opening of the valve, the assembly of the lock nuts (78) is loosened and then adjusted to a desired position using the adjusting wheel (74), whereby the assembly of the lock nuts (78) is secured again; [5] The structure of the manual diaphragm valve made of fluororesin according to claim 1, wherein the adjustment seat (71) is integrated in the upper valve cover (6a). [6] The structure of the fluororesin manual diaphragm valve according to claim 1, wherein the valve stem (4a) is a hollow stem and has a fixing end (41), a stem rod (42), a plurality of gas guide holes (413), a set screw thread (46), a locking thread (47), and a piston (44); the adjustment seat (71) has a shoulder (711), a neck portion (712), an internal space (713), an external annular groove (716), a tool receptacle (717), and a stop post (719); the upper valve body (32) provides an anti-rotation feature for the valve stem (4a) when the piston (44) is coupled to an upper valve body (32). [7] The structure of the fluororesin manual diaphragm valve according to claim 6, wherein the valve stem (4a) is a hollow stem and has a fixing end (41), a stem rod (42), a plurality of gas guide holes (413), a set screw thread (46), a locking thread (47), a piston (44), and a sliding part (45); the adjustment seat (71) has a shoulder (711), a neck part (712), an internal space (713), an external annular groove (716), a tool holder (717), a stop post (719), a fixing seat (714), and a locking thread (715); the adjustment seat (71) is used for mounting a fixing ring (72); a fixing screw sleeve (73) is used for securing the fixing ring (72); the fixing ring (72) has a flange (721), an external ring surface (722), and an internal elongated hole (723); the fixing screw sleeve (73) has an external screw thread (731), a central hole (732), and a rotating part (733);the internal elongated hole (723) is coupled to the sliding part (45) of the valve stem (4a); the anti-rotation locking of the valve stem (4a) is ensured by the fixing ring (72);

Images