Piston type micro-gap valve structure

Abstract

The invention belongs to the technical field of oil and gas storage and transportation and flow metering, and particularly discloses a piston type micro-gap valve structure which comprises a valve body shell, a piston, a valve rod and a transmission mechanism, the two ends of the valve body shell are open ends, the piston type micro-gap valve structure further comprises a piston, a valve rod and a transmission mechanism, a connecting column is perpendicularly connected to the valve body shell, and the lower portion of the connecting column extends into the valve body shell; a cavity is formed in the connecting column, the valve rod extends into the cavity of the connecting column and is in running fit with the connecting column, the transmission mechanism comprises a gear and a rack, the gear is coaxially connected with the valve rod, the rack is perpendicular to the connecting column and meshed with the gear, and the two ends of the rack penetrate through the connecting column. One end of the rack is connected with the piston, the gear can drive the rack to move transversely when the valve rod is driven to rotate, and the rack can drive the piston to open or close one end of the valve body shell through reciprocating transverse movement. According to the invention, the middle gap space when the valves are connected can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the oil and gas storage and transportation and flow measurement technical field, and particularly relates to a piston type micro-void valve structure. BACKGROUND

[0002] In the field of oil and gas storage and transportation and flow measurement, there is a case that a certain amount of oil or natural gas is filled into a container from an oil or gas pipeline, and the container needs to be separated from the pipeline. Taking the mass time method gas flow standard device in natural gas flow measurement as an example: the mass time method gas flow standard device is to obtain the gas flow by accurately measuring the mass of the gas flowing through in a period of time, and the gas flow is equal to the mass divided by the time. The measurement accuracy of the mass and the time directly affects the performance of the whole device.

[0003] The brief working steps of the device are as follows: 1. weighing the mass of the empty gas storage tank; 2. connecting the gas storage tank with the pipeline, as shown in Figure 1 ; 3. operating the reversing valve gas filling system to fill gas into the gas storage tank; 4. separating the gas storage tank from the pipeline after the gas filling is completed, as shown in Figure 2 ; 5. weighing the mass of the gas storage tank after the gas filling; and taking the mass difference of the gas storage tank before and after the gas filling as the mass of the filled gas. At the same time, since there is a section of pipeline and valve between the reversing valve gas filling system and the gas storage tank, and the mass of the gas in the section of pipeline and valve will change before and after the gas filling, the changed mass also affects the mass of the measured gas, that is, the changed mass will be added to the mass of the filled gas as a mass compensation.

[0004] Therefore, the section of pipeline and valve is also called a compensation section. In the prior art, the mass change of the gas in the compensation section cannot be directly weighed and obtained, but can only be indirectly calculated by measuring the temperature and pressure changes in the compensation section. In the compensation section, there is a small part of the mass change that is difficult to measure, that is, the mass of the gas in the gap space between the valve and the valve connection, as shown in Figure 3 、 Figure 4 . At present, this part of the gas cannot be weighed into the gas storage tank, nor can it be measured together with other gases in the compensation section.

[0005] When the gas storage tank is connected with the pipeline, the gap space will bring in an uncertain mass of gas; when the gas storage tank is separated from the pipeline, the gap space will take away an uncertain mass of gas. The mass of this part of the gas can only be estimated or ignored, and it is the only mass that cannot be directly or indirectly measured in the mass time method gas flow measurement system, becoming a measurement loss. This small part of the measurement loss is also one of the factors hindering the further improvement of the uncertainty level of the mass time method gas flow standard device. As the highest standard of natural gas flow measurement, eliminating this measurement loss has become an urgent need for the improvement of the mass time method gas flow standard device. SUMMARY

[0006] The present application provides a piston type micro-gap valve structure, which aims to reduce the intermediate gap space when the valve is connected with another valve.

[0007] The present application realizes the technical scheme as follows: a piston type micro-gap valve structure, comprising a valve body shell, both ends of the valve body shell being open ends, further comprising a piston, a valve rod and a transmission mechanism, a connecting column being vertically connected to the valve body shell, the lower part of the connecting column extending into the valve body shell, a cavity being formed in the connecting column, the valve rod extending into the cavity of the connecting column and being rotationally matched with the connecting column, the transmission mechanism comprising a gear and a rack, the gear being coaxially connected with the valve rod, the rack being perpendicular to the connecting column, the rack being engaged with the gear, both ends of the rack extending through the connecting column, and one end of the rack being connected with the piston, driving the valve rod to rotate can make the gear drive the rack to move laterally, and the reciprocating lateral movement of the rack can drive the piston to open or close one end of the valve body shell.

[0008] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0009] In the present application, driving the valve rod to rotate can drive the gear to rotate, the gear is engaged with the rack, and the gear can drive the rack and the piston on the rack to move laterally during the rotation of the gear, thereby realizing the opening and closing of the valve.

[0010] In addition, when two valves are connected in the closed state, the pistons on the two valves abut each other, which can effectively reduce the gap between the valves, so that only a very small micro-gap exists between the valves. The present application can be used to solve the problem of a small amount of gas that cannot be measured when the mass time method gas flow standard device is working in the flow measurement field. Further reducing the uncertainty of the device measurement. As the highest standard of natural gas flow measurement, the mass time method gas flow standard device, its measurement uncertainty is reduced by one point, which has a profound impact on secondary standards, working standards and working measuring instruments, and is of great significance to the traceability of flow measurement value. The present application is a key step for improving the overall measurement uncertainty of the mass time method gas flow standard device.

[0011] Further, the inner side of the valve body shell and the piston are both provided with limiting ends that match each other, and when the piston closes one end of the valve body shell, the limiting end of the piston can abut and contact with the limiting end of the inner side of the valve body shell.

[0012] Beneficial effect: such arrangement can limit the movement position of the piston, make the piston move more accurately, and make the cooperation between the two valves more accurate.

[0013] Further, the end of the piston and / or the valve body shell in contact with each other is connected with a sealing element.

[0014] Beneficial effect: the sealing element is arranged to isolate the inside of the valve from the outside, so that the valve is sealed and does not leak.

[0015] Further, the end of the piston is connected with a thickness adjusting piece.

[0016] Beneficial effect: the thickness adjusting piece is used to adapt to the thickness error of the piston, and further eliminates the gap.

[0017] Further, the thickness adjusting piece is detachably connected with the piston.

[0018] Beneficial effect: in this way, thickness adjusting pieces of different thicknesses can be replaced to adjust the gap between the two valves after they are docked, so that the size of the gap is appropriate.

[0019] Further, the inner side wall shape of the valve body shell matched with the piston matches the outer contour shape of the piston.

[0020] Beneficial effect: in this scheme, the shape of the piston can be various, as long as the inner side wall shape of the valve body shell matches the outer contour shape of the piston, so that the piston can play the role of closing the valve.

[0021] Further, the lower part of the connecting column is connected with a fairing, and the fairing covers the side of the rack away from the piston.

[0022] Beneficial effect: in this scheme, the fairing can make the fluid flow through the valve in a better flow state, so that the fluid flows more smoothly.

[0023] Further, the fairing is conical, and the axis of the fairing coincides with the symmetry line of the valve body shell.

[0024] Beneficial effect: in this way, the fluid can be effectively guided, so that the fluid is guided into the outlet end of the valve body through the fairing and flows out.

[0025] Further, the two ends of the valve body shell are connected with flanges.

[0026] Beneficial effect: the flanges are arranged to facilitate the connection and fixation of two valve bodies.

[0027] Further, a conduit is connected to the valve body shell, one end of the conduit communicates with the inside of the valve body shell, the other end of the conduit communicates with the space position when the piston closes the end of the valve body shell, and a balance valve is installed on the conduit.

[0028] Beneficial effect: in the scheme, the conduit is used for conducting the valve and the valve, and the balance valve is used for controlling the opening and closing of the conduit, so that when the balance valve is closed and the pressure in the valve is far higher than the pressure outside the valve, the valve is difficult to open, and the anti-misoperation function is realized; after the valve is connected, when the pressure in the valve is far higher than the pressure outside the valve, only the balance valve is opened, and after the pressure in and outside the valve is balanced, the valve can be easily opened. BRIEF DESCRIPTION OF DRAWINGS

[0029] The drawings described herein are used to provide further understanding of the embodiments of the present application, constitute a part of the present application, and do not constitute a limitation to the embodiments of the present application. In the drawings:

[0030] Figure 1 is a process schematic diagram when the mass time method gas flow standard device is inflated.

[0031] Figure 2 is a process schematic diagram when the mass time method gas flow standard device is weighed.

[0032] Figure 3 is a schematic diagram of the prior art ball valve and the ball valve butt joint.

[0033] Figure 4 is a schematic diagram of the prior art flat plate valve and the flat plate valve butt joint.

[0034] Figure 5 is a schematic diagram of the piston closing the valve in the piston type micro-gap valve structure provided by the embodiments of the present application.

[0035] Figure 6 is a schematic diagram of the piston opening the valve in the piston type micro-gap valve structure provided by the embodiments of the present application.

[0036] Figure 7 is a schematic diagram of the piston type micro-gap valve structure provided by the embodiments of the present application.

[0037] Figure 8 is a schematic diagram of the balance valve and the conduit cooperating with the valve body shell provided by the embodiments of the present application.

[0038] Figure 9 is a schematic diagram of the piston side being conical in the piston type micro-gap valve structure provided by the embodiments of the present application.

[0039] Figure 10 is a schematic diagram of the piston side being arc-shaped in the piston type micro-gap valve structure provided by the embodiments of the present application.

[0040] Markings in the drawings and corresponding names of parts:

[0041] 1. Valve body shell, 101 connecting column, 2. rectifier cover, 3. transmission mechanism, 4. sealing surface, 5. piston, 6. thickness adjustment plate, 7. conduit, 8. balance valve, 9. valve stem, 10. flange. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this invention are only for explaining this invention and are not intended to limit this invention.

[0043] Example 1

[0044] like Figures 5-10 As shown, this embodiment provides a piston-type micro-gap valve structure, including a valve body shell 1. Both ends of the valve body shell 1 are open ends, serving as the gas inlet and outlet. This embodiment also includes a piston 5, a valve stem 9, and a transmission mechanism 3. The valve body shell 1 has an internal cavity, and a connecting post 101 is vertically connected to it. The lower part of the connecting post 101 extends into the valve body shell 1, and a cavity is formed on the connecting post 101. In this embodiment, the cavity is formed along the height direction of the connecting post 101. The valve stem 9 extends into the cavity of the connecting post 101 and rotates with it. In practical applications, the top end of the valve stem 9 is connected to an actuator that drives its rotation. The actuator is implemented using existing technology, such as a motor mechanism.

[0045] In this embodiment, the transmission mechanism 3 includes a gear and a rack. The gear is coaxially connected to the lower part of the valve stem 9. The rack is perpendicular to the connecting column 101 and meshes with the gear. Both ends of the rack pass through the connecting column 101, and one end of the rack is connected to the piston 5 by welding, screwing, or other connection methods. Driving the valve stem 9 to rotate can cause the gear to drive the rack to move laterally. The reciprocating lateral movement of the rack can drive the piston 5 to open or close one end of the valve body shell 1, thereby realizing the function of opening or closing the valve.

[0046] Both the inner side of the valve body housing 1 and the piston 5 are provided with mutually cooperating limiting ends. In this embodiment, the right inner wall of the valve body housing 1 is provided with a stepped limiting end, and the left side of the piston 5 is provided with a stepped limiting platform, such as... Figure 5 As shown, when piston 5 closes one end of valve body housing 1, the valve is closed. The limiting end of piston 5 can abut against the limiting end on the inner side of valve body housing 1, thereby limiting the distance the piston 5 moves when closing the valve. This ensures that the distance the piston 5 moves each time it closes the valve, and it also plays a positioning role for the movement of piston 5. This makes the movement position of piston 5 more accurate, and makes the docking and matching between the two valves more compatible and more precise.

[0047] The sealing member is connected to the end of the piston 5 and / or the valve body shell 1 in contact with each other, that is, in practical application, the sealing member can be arranged only at the limiting end of the piston 5 or the valve body shell 1, or the sealing member can be arranged at the limiting end of both the piston 5 and the valve body shell 1, and in the embodiment, the sealing member is connected to the limiting end of both the piston 5 and the valve body shell 1, and the sealing member is used to improve the sealing between the piston 5 and the valve body shell 1, thereby playing a role of isolating the inside of the valve from the outside of the valve, so that the valve is sealed and does not leak. The sealing member can be an O-shaped sealing ring or a metal ring with high machining precision or a tetrafluoroethylene plastic ring.

[0048] As shown in Figure 6 , the sealing member on the limiting end of the piston 5 is in the shape of a circular truncated cone, and the sealing member on the limiting end of the valve body shell 1 is in a shape matched with the sealing member on the piston 5, that is, the inner side of the sealing member on the valve body shell 1 is a tapered surface matched with the sealing member on the piston 5, so that when the piston 5 closes the valve, the sealing member on the piston 5 is in contact with the sealing member on the valve body shell 1, thereby improving the sealing.

[0049] In the embodiment, the end of the piston 5 is connected to the thickness adjusting piece 6, the thickness adjusting piece 6 is detachably connected to the piston 5, the thickness adjusting piece 6 and the end of the piston 5 can be detachably connected through a countersunk screw, or can be fixed by being attracted by a magnet, or a groove is formed in the end of the piston 5, so that the thickness adjusting piece 6 is embedded in the groove, or threads are formed on the thickness adjusting piece 6, so that the thickness adjusting piece 6 is threadedly connected to the end of the piston 5, and the thickness adjusting piece 6 is used to adapt to the thickness error of the structure of the piston 5 and further eliminate the gap.

[0050] In the embodiment, the lower part of the connecting column 101 is connected to the fairing 2, the fairing 2 covers the side of the rack away from the piston 5, the fairing 2 is in the shape of a cone, and the axis of the fairing 2 coincides with the symmetry line of the valve body shell 1, and in the embodiment, the profile of the fairing 2 is a conical curved surface, and the fairing 2 plays a guiding role for the fluid, so that the fluid flows more smoothly.

[0051] The inner side wall of the valve body shell 1 matched with the piston 5 is matched with the outer profile shape of the piston 5, Figure 5 , Figure 9 and Figure 10 , the shape of the piston 5 is not limited to a cylindrical shape, and the side profile shape thereof can also be designed to be conical or arc-shaped

[0052] As shown in Figure 7 , the valve body shell 1 is connected to the flange plate 10 at both ends, so that when two valves are butted against each other, the flange plates 10 at the ends of the two valves can be connected to each other by bolts, thereby achieving the purpose of connecting the two valves.

[0053] The specific implementation process is as follows:

[0054] The actuator connected to the valve stem 9 drives the valve stem 9 to rotate. The valve stem 9 drives the piston 5 to move left and right through the transmission mechanism 3, thereby opening or closing the valve. Figure 5 and Figure 6 As shown, Figure 5 The valve is in the closed state. Figure 6 This indicates the valve is open. For example... Figure 7 As shown, the two valves should be connected in the closed state. After connection, there should be a slight gap between the two valves. The piston 5 end can be fitted with a thickness adjustment piece 6 of different thicknesses to adjust the gap between the two valves after connection, so that the gap size is appropriate.

[0055] Example 2, the difference between this example and Example 1 is that: in this example, the valve body shell 1 is connected to a conduit 7, combined with... Figure 8 As shown, with the sealing surface position when the valve is closed as the boundary, one end of the conduit 7 is connected to the inside of the valve body shell 1 when the valve is closed, and the other end of the conduit 7 is connected to the outside of the valve body shell 1 when the valve is closed. A balance valve 8 is installed on the conduit 7.

[0056] like Figure 7 As shown, in this embodiment, after the two valves are connected, if the pressure inside the valve is close to the pressure outside the valve, the valve can be opened directly; if the pressure inside the valve is much higher than the pressure outside the valve, the balancing valve 8 can be opened first. Figure 8 As shown, high-pressure gas inside the valve flows into the micro-gap outside the valve through conduit 7. The valve is opened after the pressure inside and outside the valve is balanced. When the valve is closed, piston 5 moves forward, and gas at the connection point can flow into the valve through conduit 7, returning to the micro-gap state. Figure 7 As shown. Before the two valves separate, close the balance valve 8 to prevent gas leakage after separation.

[0057] When the valve is closed, piston 5 moves to the right. Gas in the gap between the valves will either enter the opposite valve body or flow back into this valve body through the micro-gaps around piston 5 and conduit 7. When both valves are closed, only a tiny micro-gaps exist between them. Therefore, whether the valves are connected or disconnected, only a tiny volume of gas is introduced, resulting in a minimal change in mass. Based on the valve's sealing design, if the internal pressure is higher than the external pressure after the valve is closed, the valve's sealing performance will be enhanced, further preventing leakage. If the valve needs to be opened after the two valves are connected, and the internal pressure is higher than the external pressure, the balancing valve 8 can be opened first to balance the internal and external pressures. Once the internal and external pressures are balanced, piston 5 can be opened smoothly.

[0058] The piston 5 zero gap design is superior to the piston 5 micro gap design in terms of eliminating the problem of the intermediate gap space when the valve is connected with the valve. However, if the piston 5 valve is designed as a zero gap, the internal and external pressures of the valve at the piston 5 cannot be balanced, and when the internal pressure of the valve is much higher than the external pressure, the piston 5 valve cannot be opened due to the large pressure difference between the front and back of the piston 5. Therefore, the piston 5 micro gap design of the present application can well solve the above problems.

[0059] The piston micro gap valve disclosed in the present application can well solve the problem of the intermediate gap space when the valve is connected with the valve in the prior art. The piston micro gap valve of the present application only has a very small micro gap between the valve and the valve when the two valves are in a closed state. The present application can be used to solve the problem that a small part of the gas cannot be measured in quality time method gas flow standard device in the field of flow measurement. Further reduce the uncertainty of the device measuring quality.

[0060] According to the structure characteristics of the device of the present application, the piston micro gap valve of the present application also has a misoperation prevention function. When the internal pressure of the valve is much higher than the external pressure, it is difficult to open the valve, that is, the valve is not allowed to be opened when not connected. Only when the valves are connected, the internal and external pressures of the valve are balanced, and then the valve can be opened. The safety in operation is increased.

[0061] Meanwhile, the present application can also be used in other fields where there is no gap space between the valve and the valve when connected.

[0062] It should be noted that the above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

[0063] In the description of the present application, it should be noted that the terms "first", "second", "third" and the like are only used for differentiation and description, and cannot be understood as indicating or implying relative importance.

[0064] In the description of the present application, the terms "up", "down", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "transverse", "longitudinal" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to illustrate the relative positional relationship between the components or constituent parts, and do not particularly limit the specific installation orientation of the components or constituent parts.

[0065] In the description of the present document, some terms may be used to represent the positional or positional relationship in addition to the meaning of the terms. For example, the term "upper" may also be used to represent a certain dependent relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meaning of these terms in the present application can be understood according to the specific circumstances.

[0066] In the description of the present document, the terms "mounting", "setting", "provided with", "connected", "connected" should be broadly understood. For example, it can be fixedly connected, detachably connected, or integrally configured; it can be mechanically connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium, or internal communication between two devices, elements or components. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0067] The structure, proportion, size, etc. drawn in the drawings attached in the present application are only used to cooperate with the content disclosed in the present technical disclosure, so that those skilled in the art can understand and read, and do not have technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effect and purpose that can be achieved by the present application, should still fall within the scope of the technical content disclosed by the present application.

[0068] The terms used in the present document are those general terms currently widely used in the art in consideration of the functions of the present disclosure, but these terms can vary according to the intention of those of ordinary skill in the art, precedents, or new technology in the art. In addition, specific terms can be selected by the applicant, and in this case, the detailed meaning thereof will be described in the detailed description of the present disclosure. Therefore, the terms used in the document should not be understood as mere names, but based on the meaning of the terms and the overall description of the present disclosure.

[0069] Flowcharts or words are used in the present document to illustrate the operation steps performed according to the embodiments of the present application. It should be understood that the operation steps in the embodiments of the present application are not necessarily executed in the order recorded. On the contrary, various steps can be processed in reverse order or simultaneously as needed. At the same time, other operations can be added to these processes, or one or more steps of operation can be removed from these processes.

[0070] The above is only the preferred embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A piston micro-void valve structure comprising a valve body housing having open ends at both ends thereof, characterized in that, The valve body shell is vertically connected with a connecting column, the lower part of the connecting column extends into the valve body shell, a cavity is formed in the connecting column, the valve rod extends into the cavity of the connecting column and is rotationally connected with the connecting column, the transmission mechanism comprises a gear and a rack, the gear is coaxially connected with the valve rod, the rack is perpendicular to the connecting column, the rack is engaged with the gear, the two ends of the rack extend through the connecting column, one end of the rack is connected with the piston, and driving the valve rod to rotate can drive the gear to drive the rack to move transversely.

2. A micro-porous valve structure according to claim 1, wherein The inner side of the valve body shell and the piston are provided with limiting ends matched with each other, when the piston closes one end of the valve body shell, the limiting end of the piston can abut against the limiting end of the inner side of the valve body shell.

3. A micro-porous valve structure according to claim 2, wherein The end of the piston and / or the valve body shell is connected with a sealing element.

4. A micro-porous valve structure according to claim 1, wherein The end of the piston is connected with a thickness adjusting piece.

5. A micro-porous valve structure according to claim 4, wherein The thickness adjusting piece is detachably connected with the piston.

6. A micro-porous valve structure according to claim 1, wherein The inner side wall of the valve body shell matched with the piston matches the outer contour shape of the piston.

7. A micro-porous valve structure according to claim 1, wherein The lower part of the connecting column is connected with a fairing, and the fairing covers the side of the rack away from the piston.

8. A micro-porous valve structure according to claim 7, wherein The fairing is conical, and the axis of the fairing coincides with the symmetry line of the valve body shell.

9. A micro-porous valve structure according to claim 1, wherein The two ends of the valve body shell are connected with flanges.

10. A micro-porous valve structure according to any one of claims 1 to 9, wherein The valve body shell is connected with a conduit, one end of the conduit communicates with the inside of the valve body shell, the other end of the conduit communicates with the space position when the piston closes the end of the valve body shell, and a balance valve is installed on the conduit.

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