High-reliability balanced type high-pressure pollution discharge stop and non-return broadside valve

Abstract

The invention provides a high-reliability balanced type high-pressure sewage discharge cut-off and non-return broadside valve which comprises a valve body, a valve disc, a valve rod, a valve cover, a flap valve, a hand wheel and the like, the valve disc is controlled through the hand wheel to achieve sewage discharge medium circulation cut-off, and an outlet flap valve is passively opened and closed to achieve non-return; during cut-off, the hand wheel drives the valve rod to rotate to move the valve disc to realize opening and closing; the check work depends on the pressure difference and gravity action of the flap valve; a flap valve rotation pair is special in structure, and a special bolt and a hexagon thin nut are spot-welded after pin shaft connection; the surface of the broadside flange is subjected to ceramic spraying treatment; the balance type design reduces the operation torque of the hand wheel by forming a balance hole. Through multiple tests, the valve meets various working conditions, is high in reliability, compact in structure and good in maintenance guarantee, can effectively prevent medium backflow, can reduce the machining precision requirement, and has remarkable advantages.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid machinery, and in particular to a balanced high-pressure sewage discharge stop check side valve with high reliability. Background Art

[0002] At present, in the sewage system at the side of the ship, single or series combination check valves, stop valves, etc. are often arranged to open and close the valves to achieve the circulation, cutoff and check of the fluid medium in the sewage system.

[0003] But the following problems often occur:

[0004] 1. The functions realized by arranging a single valve are limited, and the series-combined valves occupy a large space.

[0005] Passive check valves are usually used, most of which can only realize the check function, or can also realize the shutoff function when the inlet fluid medium pressure is lower than the opening pressure of the check valve. When the check valve opening and closing parts cannot return to their positions normally, the check function fails, resulting in sewage backflow. There are also stop valves or other switch-blocking valves, which often need to be operated on-site, which is troublesome for frequently used working conditions such as toilet sewage systems.

[0006] The series combination arrangement usually consists of a check valve and a stop valve in series, which often takes up a large space and has poor security. When medium leakage, backflow or other failure modes occur, since the cause of the failure cannot be quickly determined, it is usually necessary to disassemble and inspect each valve and check the cause of the failure one by one, which consumes a lot of security resources.

[0007] 2. Passive opening and closing check valves have poor reliability under conditions of frequent use and harsh environmental conditions.

[0008] First of all, passive check valves are mostly opened and closed through the rotary pair composed of the upper valve disc and the pin shaft and other similar parts. Common causes of failure here are: ① Due to environmental factors such as vibration and impact, the valve disc and the pin shaft are prone to fall off. In addition to the failure of the main check function, the fallen parts will also flow to the downstream pipe system, causing blockage and other effects. ② The valve disc and the pin shaft are corroded by the material between the dissimilar metals or by the medium itself, and the valve is stuck in opening and closing, resulting in the valve disc unable to return to its position normally and the failure of the check function.

[0009] Secondly, most of the check valve sealing pairs adopt a hard sealing structure, that is, both sides of the sealing pair are made of metal materials or other harder materials, and most of the sealing surfaces on both sides are not treated with any surface treatment, resulting in low surface hardness and poor corrosion resistance. When subjected to long-term erosion and corrosion by sewage impurities, the sealing surface is easily damaged, resulting in failure of sealing performance. For the sealing surface of a large-diameter check valve, it often takes a lot of time to grind, and special tooling needs to be designed, resulting in high maintenance costs. Moreover, when the hard sealing structure is subjected to liquid shaking and vibration in the pipeline system, the rotational inertia of the rotary pair composed of the valve disc and the pin shaft is very small, so non-periodic collisions between the two hard sealing surfaces often occur, causing noise.

[0010] 3. There is a potential difference at the sealing surface of the dissimilar metal flange connection, which is seriously affected by galvanic corrosion.

[0011] For some special pipelines, the valve body material (including interface flange) is different from the pipeline material, such as copper valves and steel pipelines. Under this condition, at the flange connection between the valve and the pipeline, due to the potential difference between the two metals, galvanic corrosion is prone to occur on the flange connection surface, causing serious damage to the flange connection surface and failure of the flange sealing function.

[0012] 4. For high-pressure sewage pipe systems, the opening and closing torque of the stop valve is too large.

[0013] At present, the pressure of the sewage system of ships is mostly below 3MPa, and the working pressure is relatively low. The valve handwheel is usually manually operated to drive the inner valve disc to move along the axial direction of the valve stem to open and close the valve. Most of them use standard straight-through stop valves or check valves. When this type of valve is under the condition of high pressure difference between the inlet and outlet, the operating torque of the handwheel is large, and auxiliary tools are often required for opening and closing, which often causes failure modes such as valve stem bending and damage or extrusion and deformation of the sealing surface. Summary of the invention

[0014] According to the technical problems often encountered in valves mentioned above, a highly reliable balanced high-pressure sewage shut-off non-return side valve is provided. The present invention is mainly used for sewage systems at the side ends of ships, and its main functions are: to realize the circulation and cut-off of the fluid medium of the sewage system by opening and closing the valve by handwheel in the cabin, and to realize the circulation and non-return of the fluid medium of the sewage system by passively opening and closing the tongue valve at the outlet.

[0015] The technical means adopted by the present invention are as follows:

[0016] A highly reliable balanced high-pressure sewage shut-off check side valve, including: valve body, gasket, valve cover, packing, packing gland, valve stem, hand wheel, flat washer, nut, stud, nut, stud, nut, spring washer, valve disc, slotted cylindrical head screw, wedge-type anti-loosening washer, threaded bushing, special bolt, slotted cone end set screw, hexagonal thin nut, pin shaft, washer, tongue valve, sealing ring, slotted countersunk screw, sealing plate:

[0017] The threaded bushing is sleeved on the valve stem and is threadedly connected to the valve disc, and is secured against loosening by a slotted cylindrical head screw;

[0018] The valve stem is inserted from the lower end of the valve cover, the trapezoidal threaded part of the valve stem is screwed into the threaded hole at the top of the valve cover, the packing and the packing gland are sequentially mounted on the valve stem, the stud passes through the bolt hole of the packing gland and is tightened to the threaded hole of the valve cover, the nut temporarily tightens the packing gland, the hand wheel and the flat washer are mounted on the top of the valve stem and tightened with the nut;

[0019] The sealing plate is embedded in the countersunk hole on the end face of the tongue valve, the gasket is fastened to the tongue valve with a slotted cone-end set screw and the sealing plate is compacted, the special bolt is tightened in the threaded hole on the end face of the valve body bevel flange, the tongue valve and the special bolt are pre-assembled to form a set screw hole and tightened with a slotted cone-end set screw, the tongue valve is connected with the special bolt pin with a pin shaft and screwed into a hexagonal thin nut;

[0020] The gasket is sleeved on the flange end stop at the bottom of the valve cover, the stud is tightened on the flange end threaded hole in the valve body, and the valve cover is integrally inserted into the valve body and fastened with a nut.

[0021] Furthermore, the valve stem and the valve cover are connected by a threaded connection, and the handwheel is manually turned. The handwheel cooperates with the hexagonal structure of the valve stem head to drive the valve stem to rotate, and the valve stem moves in the axial direction, thereby driving the valve disc to move in the axial direction of the valve stem to realize the opening and closing operation of the valve.

[0022] Furthermore, the flap valve is returned to its original position by means of a flap valve rotation auxiliary structure between the flap valve and the pin shaft.

[0023] Furthermore, the tongue valve rotation sub-structure is to align the center lines of the pin shaft holes of the tongue valve and the special bolt, the pin shaft is inserted into the pin shaft holes of the tongue valve and the special bolt, the threaded structure at the end of the special bolt is connected with the hexagonal thin nut, and after the assembly is completed, the special bolt and the hexagonal thin nut are welded by spot welding.

[0024] Furthermore, the tongue valve sealing pair adopts a detachable soft sealing structure, the sealing plate is embedded in the countersunk hole on the end face of the tongue valve, the gasket is fastened to the tongue valve with a slotted cone-end set screw and compacts the sealing plate, and the sealing ring is used to seal the relevant parts.

[0025] Furthermore, a balancing hole is provided between the inner flow passage of the valve body inlet and the flange in the valve body.

[0026] Furthermore, the packing is used to seal the gap between the valve stem and the valve cover, and the packing gland is fastened to the valve cover through studs and nuts to compact the packing to ensure the sealing effect.

[0027] Due to the adoption of the above technical solution, compared with the prior art, the present invention has the following advantages:

[0028] 1. The present invention provides a highly reliable balanced high-pressure sewage shut-off check side valve, which has both shut-off and check functions. When the check function of the tongue valve fails, the shut-off part valve disc can be fully closed through emergency operation to prevent medium backflow. When the shut-off part valve disc is fully closed, the tongue valve can be disassembled and repaired in situ without discharging the upstream piping medium. Compared with the arrangement of the check valve and the shut-off valve in series, the structure is more compact and has better maintainability and security.

[0029] 2. The invention provides a highly reliable balanced high-pressure sewage shut-off check valve on the side of the ship, which performs ceramic spraying treatment on the connecting surface of the side flange to prevent galvanic corrosion at the connection of dissimilar metal flanges.

[0030] 3. The present invention provides a highly reliable balanced high-pressure sewage shut-off non-return side valve, which forms a balancing cavity between the upper and lower cavities of the valve disc by opening a balancing hole between the flow channel inside the valve body inlet and the flange in the valve body. Under high-pressure working conditions, a smaller handwheel operating torque can be provided. Under the inlet and outlet pressure difference of 5MPa, the handwheel opening operating torque is only 57N / m, and the handwheel closing operating torque is only 42N / m.

[0031] 4. The present invention provides a highly reliable balanced high-pressure sewage shut-off non-return side valve with a tongue valve rotary sub-structure. Compared with opening a hole on the pin shaft and inserting a cotter pin, this structure is more stable and is not easily broken by the cotter pin under the influence of impact, vibration, etc.

[0032] 5. The present invention provides a highly reliable balanced high-pressure sewage shut-off non-return side valve, in which the tongue valve sealing pair adopts a detachable soft sealing structure. Compared with the hard sealing structure that needs to be ground and the soft sealing structure that is difficult to remove such as vulcanized rubber, the detachable structure has better security and can avoid the noise generated by the hard sealing structure under random collision.

[0033] Based on the above reasons, the present invention can be widely used in the field of fluid machinery technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 It is a cross-sectional view of a high-reliability balanced high-pressure sewage discharge stop check side valve described in the present invention;

[0036] Figure 2 This is a schematic diagram of the structure of the A surface of a high-reliability balanced high-pressure sewage shut-off check side valve of the present invention;

[0037] Figure 3 It is a three-dimensional structural diagram of a high-reliability balanced high-pressure sewage discharge stop check side valve described in the present invention.

[0038] In the figure: 1. valve body; 2. gasket; 3. valve cover; 4. packing; 5. packing gland; 6. valve stem; 7. handwheel; 8. identification plate; 9. nut; 10. stud; 11. nut; 12. stud; 13. nut; 14. spring washer; 15. valve disc; 16. slotted cylindrical head screw; 17. wedge-type anti-loosening washer; 18. threaded bushing; 19. special bolt; 20. slotted cone-end set screw; 21. hexagonal thin nut; 22. pin; 23. washer; 24. tongue valve; 25. sealing ring; 26. slotted countersunk screw; 27. sealing plate. DETAILED DESCRIPTION

[0039] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0042] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, the numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0043] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0044] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0045] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0046] Example 1

[0047] like Figures 1 to 3 As shown, the present invention provides a high-reliability balanced high-pressure sewage stop check side valve, comprising: a valve body 1, a gasket 2, a valve cover 3, a packing 4, a packing gland 5, a valve stem 6, a hand wheel 7, a flat washer 8, a nut 9, a stud 10, a nut 11, a stud 12, a nut 13, a spring washer 14, a valve disc 15, a slotted cylindrical head screw 16, a wedge-type anti-loosening washer 17, a threaded bushing 18, a special bolt 19, a slotted cone-end set screw 20, a hexagonal thin nut 22, a pin 22, a washer 23, a tongue valve 24, a sealing ring 25, a slotted countersunk screw 26, and a sealing plate 27;

[0048] The threaded bushing 18 is sleeved on the valve stem 6, and the threaded bushing 18 is connected to the valve disc 15 through threads, and a threaded hole is drilled at the contact end surface, and a slotted cylindrical head screw 16 is screwed into the threaded hole to prevent the threaded bushing 18 and the valve disc 15 from loosening and tightening;

[0049] The valve stem 6 is inserted from the valve stem hole at the lower end of the valve cover 3 until the trapezoidal threaded portion of the valve stem 6 slightly exceeds the upper end surface of the valve stem hole of the valve cover 3, and the packing 4 and the packing gland 5 are sequentially mounted on the valve stem 6, and the valve stem 6 is continuously pushed and installed, and the trapezoidal threaded portion of the valve stem 6 is screwed into the threaded hole at the top of the valve cover 3. The studs 10 are sequentially passed through the bolt holes of the packing gland 5 and tightened into the threaded holes of the valve cover 3, and the packing gland 5 is temporarily tightened with the nut 9 to compact the packing 4. The hand wheel 7 and the flat washer 8 are sequentially mounted on the top of the valve stem 6, and are tightened to the valve stem 6 with the nut 9;

[0050] The sealing plate 27 is embedded in the countersunk hole on the end face of the tongue valve 24. The gasket 23 is fastened to the tongue valve 24 with the slotted cone-end set screw 20, and the sealing plate 27 is pressed and compacted. The 2 gaskets are fitted on the threaded end of the special bolt 19, and the special bolt 19 is tightened into the threaded hole on the end face of the bevel flange of the valve body 1, and the center line of the pin hole of the special bolt 19 is ensured to be perpendicular to the center line of the bevel flange pipeline of the valve body 1;

[0051] The flap valve 24 is pre-assembled with the special bolt 19, and the relative position between the special bolt pin hole and the valve body 1 is confirmed to ensure that the sealing plate 27 of the flap valve 24 is in uniform contact with the sealing surface of the valve body 1, and the sealing is effective. A set screw hole is provided, and the slotted cone end set screw 20 is tightened into the provided screw hole, and the flap valve 24 is connected with the special bolt 19 by the pin shaft 22, and the hexagonal thin nut 22 is screwed into the thread of the rear end of the special bolt 19;

[0052] The hand wheel 7 is rotated to lift the valve disc 15 to the highest point, the gasket 2 is fitted on the stopper of the flange end face at the bottom of the valve cover 3, and the studs 12 are tightened in turn into the threaded holes on the flange end face of the valve body 1;

[0053] The valve cover 3 is integrally inserted into the valve body 1 , so that the studs 12 pass through the bolt holes of the flange of the valve cover 3 in sequence, and are fastened to the valve body 1 with nuts 13 .

[0054] Furthermore, the valve stem and the valve cover are connected by a threaded connection, and the handwheel is manually turned. The handwheel and the hexagonal structure of the valve stem head cooperate to drive the valve stem to rotate, and the valve stem moves in the axial direction, thereby driving the valve disc to move in the axial direction of the valve stem to realize the opening and closing operation of the valve. When the sealing surface of the valve disc contacts the sealing surface of the valve body and forms the required sealing pressure ratio, the valve shut-off function is realized.

[0055] Furthermore, the flap valve is returned to its original position by means of a flap valve rotation auxiliary structure between the flap valve and the pin shaft.

[0056] Furthermore, the tongue valve rotation sub-structure is to align the center lines of the pin shaft holes of the tongue valve and the special bolt, the pin shaft is inserted into the pin shaft holes of the tongue valve and the special bolt, the threaded structure at the end of the special bolt is connected with the hexagonal thin nut, and after the assembly is completed, the special bolt and the hexagonal thin nut are welded by spot welding.

[0057] Furthermore, the tongue valve sealing pair adopts a detachable soft sealing structure, the sealing plate is embedded in the countersunk hole on the end face of the tongue valve, the gasket is fastened to the tongue valve with a slotted cone-end set screw and compacts the sealing plate, and the sealing ring is used to seal the relevant parts.

[0058] Furthermore, a balancing hole is provided between the inner flow passage of the valve body inlet and the flange in the valve body.

[0059] Furthermore, when the valve shutoff part is fully closed, the medium at the inlet flows into the cavity formed by the valve cover 3 and the valve disc 15 through the balancing hole. The inlet medium pressure is the same as the pressure in the cavity, forming a balance. At this time, when the valve shutoff part is fully opened, it is only necessary to overcome the friction torque between the valve stem 6 and other parts plus the sealing specific pressure. The operating torque of the hand wheel 7 is tested. Under the inlet and outlet pressure difference of 5MPa, the opening operating torque of the hand wheel 7 is only 57N / m, and the closing operating torque of the hand wheel 7 is only 42N / m.

[0060] Furthermore, the packing is used to seal the gap between the valve stem and the valve cover, and the packing gland is fastened to the valve cover through studs and nuts to compact the packing to ensure the sealing effect.

[0061] Furthermore, the connecting surfaces of the side flanges are treated with ceramic spraying, and the flow channel inside the valve body and the outer cylindrical surface and back of the side flanges are extended by spraying to ensure the continuity of the coating and prevent galvanic corrosion at the connection between dissimilar metal flanges.

[0062] Example 2

[0063] Provide a high-reliability balanced high-pressure sewage stop check side valve periodic vibration test, respectively along three orthogonal axial directions, apply vibration frequency 1Hz ~ 16Hz, displacement amplitude 1.0mm; vibration frequency 16Hz ~ 60Hz, acceleration amplitude 10m / s2; sweep rate 1oct / min; 10 sweep cycles; no dangerous frequency; test frequency 60Hz; vibration time 2h / axial direction. Test results: no dangerous frequency, after the test, no parts loose, no structural deformation, no functional or safety-threatening mechanical damage, normal operation.

[0064] Example 3

[0065] Provide a high-reliability random vibration test for balanced high-pressure sewage stop check side valve, vibration frequency 1Hz ~ 100Hz; acceleration spectrum density 0.001g2 / Hz; vibration time 2h / axial. Test results: no dangerous frequency, after the test, no parts loose, no structural deformation, no functional or safety-threatening mechanical damage, normal operation.

[0066] Example 4

[0067] A high-reliability balanced high-pressure sewage shut-off check side valve is provided. After the periodic vibration test and random vibration test, the shut-off part and the check part sealing test are carried out. The valve shut-off part is fully closed, and the test fixture is installed at the inlet flange of the valve body 1. The cavity between the test fixture and the inlet flange of the valve body 1 is filled with water to remove the air in the cavity, and the pressure is gradually increased to 6.25MPa. The test time is 10 minutes. The test results are: there is no leakage at the sealing pair during the test, and the test pressure does not decrease significantly. The sealing pair composed of the tongue valve 24 and the valve body 1 is tested for tightness. A pressure of 0.3MPa is applied to the tongue valve 24 in the reverse direction, and the pressure is maintained for 10 minutes. Zero leakage of the medium can be achieved at the sealing surface; a pressure of 6.25MPa is applied to the tongue valve 24 in the reverse direction, and the pressure is maintained for 10 minutes. Zero leakage of the medium can be achieved at the sealing surface.

[0068] Example 5

[0069] Provide an impact test of a balanced high-reliability high-pressure sewage shut-off check side valve, and apply three impacts along three orthogonal axes: the drop height is 0.3m, 0.9m, and 1.5m respectively. Test results: no dangerous frequency; after the test, no parts are loose, no structural deformation, no functional or safety-threatening mechanical damage, and the operation is normal. After the impact test, the sealing test of the shut-off part and the check part is carried out: the shut-off part of the valve is fully closed, the test fixture is installed at the inlet flange of the valve body 1, and the cavity between the test fixture and the inlet flange of the valve body 1 is filled with water to remove the air in the cavity, and the pressure is gradually increased to 6.25MPa. The test time is 10 minutes. The test results are: there is no leakage at the sealing pair during the test, and the test pressure does not decrease significantly. The sealing pair composed of the tongue valve 24 and the valve body 1 is subjected to a tightness test. A pressure of 0.3 MPa is applied to the tongue valve 24 in the reverse direction and the pressure is maintained for 10 minutes. Zero leakage of the medium at the sealing surface can be achieved. A pressure of 6.25 MPa is applied to the tongue valve 24 in the reverse direction and the pressure is maintained for 10 minutes. Zero leakage of the medium at the sealing surface can be achieved.

[0070] Example 6

[0071] Provide a highly reliable tilting and swinging test for a balanced high-pressure sewage shut-off check side valve, with a pitch angle of ±15°, a roll angle of ±15°, a pitch angle of ±30°, a pitch period of 7s, a roll angle of ±30°, and a roll period of 10s; each lasting for 30 minutes. After the test, there is no loosening of parts, no structural deformation, no functional or safety-threatening mechanical damage, and the operation is normal. After the tilting and swinging test is completed, the sealing test of the shut-off part and the check part is carried out: the shut-off part of the valve is fully closed, the test fixture is installed at the inlet flange of the valve body 1, the cavity between the test fixture and the inlet flange of the valve body 1 is filled with water to remove the air in the cavity, and the pressure is gradually increased to 6.25MPa. The test time is 10 minutes. The test results are: there is no leakage at the sealing pair during the test, and the test pressure does not decrease significantly. The sealing pair composed of the tongue valve 24 and the valve body 1 is subjected to a tightness test. A pressure of 0.3 MPa is applied to the tongue valve 24 in the reverse direction and the pressure is maintained for 10 minutes. Zero leakage of the medium at the sealing surface can be achieved. A pressure of 6.25 MPa is applied to the tongue valve 24 in the reverse direction and the pressure is maintained for 10 minutes. Zero leakage of the medium at the sealing surface can be achieved.

[0072] Example 7

[0073] Provide a reliability test for a high-reliability balanced high-pressure sewage shut-off check side valve. Under a pressure difference of 5.0MPa, the action cycle is 1500 times. After every 500 actions and tests, the sealing test of the shut-off part and the check part is carried out: the shut-off part of the valve is fully closed, the test fixture is installed at the inlet flange of the valve body 1, the cavity between the test fixture and the inlet flange of the valve body 1 is filled with water to remove the air in the cavity, and the pressure is gradually increased to 6.25MPa. The test time is 10 minutes. The test results are: there is no leakage at the sealing pair during the test, and the test pressure does not decrease significantly. The sealing pair composed of the tongue valve 24 and the valve body 1 is tested for tightness. A pressure of 0.3MPa is applied to the tongue valve 24 in the reverse direction, and the pressure is maintained for 10 minutes. Zero leakage of the medium can be achieved at the sealing surface; a pressure of 6.25MPa is applied to the tongue valve 24 in the reverse direction, and the pressure is maintained for 10 minutes. Zero leakage of the medium can be achieved at the sealing surface.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-reliability balanced high-pressure sewage shut-off check valve, characterized in that: include: Valve body, gasket, valve cover, packing, packing gland, valve stem, handwheel, flat washer, nut, stud, nut, stud, nut, spring washer, valve disc, slotted cylindrical head screw, wedge-type anti-loosening washer, threaded bushing, special bolt, slotted cone-end set screw, hexagonal thin nut, pin, washer, tongue valve, sealing ring, slotted countersunk screw, sealing plate: The threaded bushing is sleeved on the valve stem and is threadedly connected to the valve disc, and is secured against loosening by a slotted cylindrical head screw; The valve stem is inserted from the lower end of the valve cover, the trapezoidal threaded part of the valve stem is screwed into the threaded hole at the top of the valve cover, the packing and the packing gland are sequentially mounted on the valve stem, the stud passes through the bolt hole of the packing gland and is tightened to the threaded hole of the valve cover, the nut temporarily tightens the packing gland, the hand wheel and the flat washer are mounted on the top of the valve stem and tightened with the nut; The sealing plate is embedded in the countersunk hole on the end face of the tongue valve, the gasket is fastened to the tongue valve with a slotted cone-end set screw and the sealing plate is compacted, the special bolt is tightened in the threaded hole on the end face of the valve body bevel flange, the tongue valve and the special bolt are pre-assembled to form a set screw hole and tightened with a slotted cone-end set screw, the tongue valve is connected with the special bolt pin with a pin shaft and screwed into a hexagonal thin nut; The gasket is sleeved on the flange end stop at the bottom of the valve cover, the stud is tightened on the flange end threaded hole in the valve body, and the valve cover is integrally inserted into the valve body and fastened with a nut.

2. A high-reliability balanced high-pressure sewage shut-off check valve according to claim 1, characterized in that: The valve stem and the valve cover are connected by threads. The hand wheel is manually turned, and the hand wheel cooperates with the hexagonal structure of the valve stem head to drive the valve stem to rotate, and the valve stem moves in the axial direction, thereby driving the valve disc to move in the axial direction of the valve stem to realize the opening and closing operation of the valve.

3. A high-reliability balanced high-pressure sewage shut-off check valve according to claim 1, characterized in that: The flap valve is returned to its original position by means of a flap valve rotation auxiliary structure between the flap valve and the pin shaft.

4. A high-reliability balanced high-pressure sewage shut-off check side valve according to claim 3, characterized in that: The described tongue valve rotary auxiliary structure is to align the center lines of the pin shaft holes of the tongue valve and the special bolt, the pin shaft is inserted into the pin shaft holes of the tongue valve and the special bolt, the threaded structure at the end of the special bolt is connected with the hexagonal thin nut, and after the assembly is completed, the special bolt and the hexagonal thin nut are welded by spot welding.

5. A high-reliability balanced high-pressure sewage shut-off check valve according to claim 3, characterized in that: The tongue valve sealing pair adopts a detachable soft sealing structure, the sealing plate is embedded in the countersunk hole on the end face of the tongue valve, the gasket is fastened to the tongue valve and compacted with a slotted cone-end set screw, and the sealing ring is used to seal relevant parts.

6. A high-reliability balanced high-pressure sewage shut-off check valve according to claim 1, characterized in that: A balancing hole is provided between the flow passage inside the valve body inlet and the flange in the valve body.

7. A high-reliability balanced high-pressure sewage shut-off check valve according to claim 1, characterized in that: The packing is used to seal the gap between the valve stem and the valve cover. The packing gland is fastened to the valve cover through studs and nuts to compact the packing to ensure the sealing effect.

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