Valve with leakage rate control function and control method thereof

Abstract

The invention belongs to the technical field of valves, and particularly relates to a valve with a leakage rate control function, which comprises a valve body, a flow guide groove is formed in the valve body, a sliding block seat is assembled at the top of the valve body, a connecting nut is in threaded connection with the side wall between the sliding block seat and the valve body, and a valve rod is in threaded connection with the interior of the sliding block seat. The top end of the valve rod extends to the outer side of the sliding block seat and is fixedly connected with a rotating handle, the bottom end of the valve rod is fixedly connected with a sliding block, and a valve element assembly is arranged in an inner cavity of the valve body. The valve element assembly comprises a movable rod arranged in the valve body, the section of the movable rod is in a T shape, a spring is arranged between the side wall of the movable rod and an inner cavity of the valve body in a sleeved mode, a valve rod embedding barrel is assembled on the portion, close to the bottom end, of the side wall of the movable rod, and a sealing piece is arranged in the valve rod embedding barrel. The high sealing effect can be effectively achieved, the phenomenon of leakage when the valve is closed is avoided, and the stability of the valve is effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of valves, and in particular relates to a valve with a leakage rate control function and a control method thereof. Background Art

[0002] Semiconductor material MO source is a high-purity metal organic compound and a supporting raw material for the modern compound semiconductor industry. MO source is in liquid state and needs to be stored, transported, and supplied in the production and R&D process.

[0003] Since MO sources usually contain corrosive chemicals, which may cause corrosion or wear of valve materials, and MO source gases are usually highly volatile and reactive, the sealing performance of the valve must be very reliable, otherwise gas leakage may occur. This will not only lead to material waste, but also may affect the safety of the equipment; at this time, a high-performance valve that can meet ultra-high purity, high temperature resistance, acid and alkali resistance, and effective control of leakage rate is needed. Summary of the invention

[0004] The object of the present invention is to provide a valve with a leakage rate control function and a control method thereof, which can effectively achieve a high sealing effect, avoid leakage when the valve is closed, and effectively improve its stability.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A valve with a leakage rate control function comprises a valve body, a guide groove is provided in the valve body, a slider seat is assembled on the top of the valve body, a connecting nut is threadedly connected on the side wall between the slider seat and the valve body, a valve stem is threadedly connected to the slider seat, the top end of the valve stem extends to the outside of the slider seat and is fixedly connected to a rotating handle, the bottom end of the valve stem is fixedly connected to a slider, and a valve core assembly is arranged in the inner cavity of the valve body.

[0007] Furthermore, the valve core assembly includes a movable rod arranged in the valve body, the cross-section of the movable rod is T-shaped, a spring is sleeved between the side wall of the movable rod and the inner cavity of the valve body, the side wall of the movable rod is equipped with a valve stem insert near the bottom end, and a seal is arranged in the valve stem insert.

[0008] Furthermore, the sealing member comprises a valve stem bushing arranged in the valve stem insert tube, an insert is assembled in the valve stem bushing, and the bottom end surface of the insert is conical.

[0009] Furthermore, the side wall of the valve stem bushing is distributed in a stepped manner, and the valve stem bushing abuts against the inner wall of the valve stem embedded cylinder.

[0010] Furthermore, the top end surface of the valve body is distributed in a stepped manner, and a gasket is installed between the valve body and the slider seat.

[0011] Furthermore, a diaphragm is installed between the valve body and the slider seat and above the gasket.

[0012] Furthermore, a force-bearing hole is provided on the side wall of the rotating handle.

[0013] Furthermore, a drainage groove is provided at the bottom of the inner cavity of the valve body, and the bottom ends of the valve stem embedded cylinder and the valve stem bushing are both against the drainage groove.

[0014] Furthermore, the valve stem insert and the valve stem bushing are interference fit or clearance fit, the interference amount is 0 to 0.08 mm, and the clearance amount is 0 to +0.05 mm.

[0015] A control method for a valve having a leakage rate control function, the control method comprising the following steps:

[0016] S1: Turn the rotary handle clockwise to drive the valve stem to rotate, and the valve stem drives the slider to move downward. The diaphragm is deformed downward by force, driving the valve core assembly to operate;

[0017] S2: The slider drives the movable rod to move downward through the diaphragm, and the movable rod drives the valve stem insert and the valve stem bushing to move downward. At the same time, the spring is compressed to close and seal the valve;

[0018] S3: When the valve needs to be opened, turn the rotary handle counterclockwise to drive the valve stem to rotate, and the valve stem drives the slider to move upward. The spring rebound force drives the movable rod to push up the diaphragm, and the valve core assembly is lifted upward;

[0019] S4: According to the degree of loosening of the valve stem driven by the rotating handle and the rebound force of the spring, the valve stem insert and the valve stem bushing move upward, and the gap between them and the drainage groove increases, thus opening the valve.

[0020] The technical effects achieved by the present invention are:

[0021] A valve with a leakage rate control function and a control method thereof of the present invention can meet normal use without leakage or bubble problems when closed and opened under a torque of 5N / M and in an internal leakage inspection according to 4.0x10-9mbar.L / s, through the mutual cooperation among the valve body, the slider seat, the valve stem, the rotating handle and the valve core assembly, and by improving the sealing performance of the valve stem insert and the valve stem bushing, and can effectively seal at a temperature of +115°C-+10°C without leakage or bubble problems, and can effectively seal at a temperature of +115°C-+10°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a stereogram of an embodiment of the present invention;

[0023] Figure 2 is a schematic cross-sectional structural diagram of an embodiment of the present invention;

[0024] Figure 3 is a three-dimensional diagram of a valve core assembly according to an embodiment of the present invention;

[0025] Figure 4 is a schematic cross-sectional structural diagram of a valve core assembly according to an embodiment of the present invention;

[0026] Figure 5 Schematic diagram of the structure of the valve stem bushing and the insert in the embodiment of the present invention;

[0027] Figure 6 is a schematic diagram of the structure of an insert according to an embodiment of the present invention;

[0028] Figure 7 is a schematic cross-sectional structural diagram of a valve stem bushing according to an embodiment of the present invention;

[0029] Figure 8 Embodiment of the present invention Figure 2 A in the enlarged view;

[0030] Fig. 9 is a schematic diagram of a valve stem bushing according to an embodiment of the present invention magnified 20 times;

[0031] Fig.10 is a schematic diagram of a valve stem bushing after life test according to an embodiment of the present invention;

[0032] Fig.11 is a test statistical diagram after the valve core roughness is improved in the test example of the present invention;

[0033] Fig.12 It is a schematic diagram of adding a limit to the valve core in the test example of the present invention;

[0034] Fig.13 This is a schematic diagram of a test example of the present invention in which the valve core is assembled and placed in a high temperature box at 115°C for 12 hours;

[0035] Fig.14 This is a schematic diagram of the changes of the insert at 115°C for 12 hours in the test example of the present invention;

[0036] Fig.15 Schematic diagram of three states of PCTFE in the test example of the present invention.

[0037] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0038] 1. Valve body; 2. Connecting nut; 3. Slider seat; 4. Rotating handle; 5. Valve stem; 6. Slider; 7. Movable rod; 8. Spring; 9. Valve stem insert; 10. Valve stem bushing; 11. Insert; 12. Gasket; 13. Diaphragm; 14. Force hole; 15. Drainage groove. DETAILED DESCRIPTION

[0039] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific embodiments of the present invention, and does not strictly limit the scope of protection of the specific claims of the present invention.

[0040] Embodiment 1:

[0041] like Figure 1-Figure 8 As shown, a valve with a leakage rate control function includes a valve body 1, a guide groove is opened in the valve body 1, a slider seat 3 is assembled on the top of the valve body 1, a connecting nut 2 is threadedly connected on the side wall between the slider seat 3 and the valve body 1, a valve stem 5 is threadedly connected to the slider seat 3, the top end of the valve stem 5 extends to the outside of the slider seat 3 and is fixedly connected to a rotating handle 4, the bottom end of the valve stem 5 is fixedly connected to a slider 6, and a valve core assembly is arranged in the inner cavity of the valve body 1.

[0042] like Figure 3 and Figure 4 As shown, the valve core assembly includes a movable rod 7 arranged in the valve body 1. The cross-section of the movable rod 7 is T-shaped. A spring 8 is sleeved between the side wall of the movable rod 7 and the inner cavity of the valve body 1. A valve stem insert 9 is installed near the bottom end of the side wall of the movable rod 7, and a seal is arranged in the valve stem insert 9.

[0043] The sealing member comprises a valve stem bushing 10 arranged in a valve stem insert cylinder 9, an insert 11 is assembled in the valve stem bushing 10, and the bottom end surface of the insert 11 is conical.

[0044] Specifically, the valve core assembly is the focus of this solution, which is used to increase the sealing performance of the valve and reduce the valve leakage rate by improving the matching relationship between the valve stem insert 9, the valve stem bushing 10 and the insert 11.

[0045] like Figure 5 and Figure 7 As shown, the side wall of the valve stem bushing 10 is distributed in a stepped manner, and the valve stem bushing 10 abuts against the inner wall of the valve stem insert 9. The valve stem insert 9 and the valve stem bushing 10 are interference fit or clearance fit, with the interference amount being 0 to 0.08 mm and the clearance amount being 0 to +0.05 mm.

[0046] Among them, after testing, it was found that the valve stem bushing 10 in this solution had a collapsed edge phenomenon. The main reason was that the design interference between the valve stem insert 9 and the valve stem bushing 10 in the valve core assembly was too large, and the valve stem bushing 10 was squeezed out during assembly. As a result, the valve core collapsed after 100 switches in the life test;

[0047] like Fig. 9As shown, the original maximum interference fit is 0.08mm, and the minimum interference fit is 0mm. After the two are assembled, the valve stem bushing 10 is extruded and particles and burrs are generated. After the switching life, the valve stem bushing 10 and the valve body 1 are squeezed up and down, causing the valve stem bushing 10 to collapse. The adjusted interference fit and clearance fit dimensions are as follows:

[0048] Table 1: Adjustment of valve stem insert dimensions

[0049]

[0050]

[0051] Test conditions: The modified valve stem insert 9 is installed on the valve core assembly, and the valve is opened and closed with 75PSIG pressure. After 100 times of life, the valve is observed under a 10x magnifying glass. The test results are as follows: Fig.10 As shown, there is no extrusion of the valve stem bushing after the change, and no particles or burrs are generated. The valve stem bushing 10 after the change will not be extruded after the life test, which meets the requirements.

[0052] like Figure 8 As shown, the top end surface of the valve body 1 is distributed in a stepped manner, and a gasket 12 is installed between the valve body 1 and the slider seat 3.

[0053] A diaphragm 13 is mounted between the valve body 1 and the slider seat 3 and above the gasket 12 .

[0054] The following benefits are also achieved by providing the gasket 12 and the diaphragm 13:

[0055] Sealing: The gasket 12 and the diaphragm 13 can provide a sealing function to prevent leakage at the connection between the valve body 1 and the pipeline or other equipment, ensure that the fluid does not leak, and maintain the pressure and flow of the system stable;

[0056] Prevent corrosion and wear: The gasket 12 and the diaphragm 13 can isolate the valve body 1 from direct contact with the fluid, thereby reducing the impact of corrosion and wear on the valve body 1 and extending the service life of the valve body 1;

[0057] Adapt to thermal expansion and contraction: The gasket 12 and the diaphragm 13 have a certain elasticity, which can adapt to the thermal expansion and contraction of the valve body 1 and the pipeline caused by temperature changes and maintain a good sealing state.

[0058] like Figure 2 As shown, a force hole 14 is provided on the side wall of the rotary handle 4. The force hole 14 is provided to facilitate the removal and replacement of the rotary handle 4. On the other hand, when the valve stem 5 is rusted or the hand cannot rotate, an external tool can be inserted into the force hole 14 to rotate the rotary handle 4.

[0059] like Figure 2As shown, a drainage groove 15 is provided at the bottom of the inner cavity of the valve body 1, and the bottom ends of the valve stem insert 9 and the valve stem bushing 10 are both against the drainage groove 15. By providing the drainage groove 15, when the valve stem bushing 10 moves upward to open the valve, the liquid can flow out quickly through the drainage groove 15, thereby increasing the flow rate of the liquid.

[0060] Embodiment 2:

[0061] A control method for a valve having a leakage rate control function, the control method comprising the following steps:

[0062] S1: Turn the rotary handle 4 clockwise to drive the valve stem 5 to rotate, and the valve stem 5 drives the slider 6 to move downward, and the diaphragm 13 is deformed downward by force, driving the valve core assembly to operate;

[0063] S2: The slider 6 drives the movable rod 7 to move downward through the diaphragm 13, and the movable rod 7 drives the valve stem insert 9 and the valve stem bushing 10 to move downward. At the same time, the spring 8 is compressed to close and seal the valve;

[0064] S3: When the valve needs to be opened, the rotating handle 4 is turned counterclockwise to drive the valve stem 5 to rotate, and the valve stem 5 drives the slider 6 to move upward, and the rebound force of the spring 8 drives the movable rod 7 to push up the diaphragm 13, and the valve core assembly is lifted upward;

[0065] S4: According to the degree of loosening of the valve stem 5 driven by the rotating handle 4 and the rebound force of the spring 8, the valve stem insert 9 and the valve stem bushing 10 move upward, and the gap between them and the drainage groove 15 increases, thereby opening the valve.

[0066] Test example:

[0067] Test after changing the valve core roughness:

[0068] Test item: High temperature test

[0069] Test method: Use 5N / m torque to tighten the handle valve stem to close the valve, keep it at a high temperature of 115 degrees Celsius for 12 hours, and perform helium internal leakage test. The test standard is 4.0*10-10Pa m 3 / s, such as Fig.11 shown.

[0070] Conclusion: After tightening the assembly with 5N / m, the helium test for internal leakage is qualified; after 12 hours of high temperature, helium test internal leakage may occur in high temperature and normal temperature states; after high temperature, the helium test for closing the valve again with 5N / m is qualified;

[0071] The factors that may affect the existence of helium internal leakage include poor valve core assembly consistency, which leads to the control of the valve core installation height during assembly and the prevention of eccentricity;

[0072] like Fig.12As shown, before the improvement, the valve core is installed without limit, and it is tightened by feeling, which will cause height inconsistency; in the improved version A, a hard limit is added, but when assembling the lower valve stem insert in the middle, the circumference is easily eccentric, resulting in eccentricity and difficulty in pressing; in the improved final version, when installing the lower valve stem insert, ensure concentricity before pressing downward.

[0073] Conclusion: There is still internal leakage;

[0074] The main factors may include the thermal expansion and contraction of the valve core after high temperature. After the valve core is assembled, put it into a high temperature box at 115℃ for 12 hours and observe the changes in the valve core. Fig.13 As shown;

[0075] Conclusion: PCTFE cracking was found in the valve core after 12 hours at 115℃. There were 5 valve cores installed, 2 of which were cracked. There was one protrusion in the insert 11 after 12 hours at 115℃. Fig.14 As shown;

[0076] In summary, the main factor for the PCTFE cracking after the valve core was exposed to a high temperature of 115°C for 12 hours is that the valve core has a large interference fit, which leads to cracks after assembly.

[0077] like Fig.12 As shown, the PCTEF material was tested at a high temperature of 115°C for 12 hours:

[0078] PCTFE is made according to Fig.15 Three states, put into 115℃, 12h high temperature, then take out and observe whether there are cracks under 10x microscope;

[0079] Test results: No cracks in all three states;

[0080] Adjust the valve core assembly interference to observe whether it cracks after high temperature:

[0081] Table 2: Comparison table of interference before and after modification:

[0082]

[0083]

[0084] Conclusion: Reducing the interference fit will prevent PCTFE from cracking after high temperature.

[0085] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. A valve with a leakage rate control function, characterized in that: The valve body (1) comprises a valve body (1), wherein a guide groove is provided in the valve body (1), a slider seat (3) is mounted on the top of the valve body (1), a connecting nut (2) is threadedly connected on the side wall between the slider seat (3) and the valve body (1), a valve stem (5) is threadedly connected to the inner thread of the slider seat (3), the top end of the valve stem (5) extends to the outside of the slider seat (3) and is fixedly connected to a rotating handle (4), the bottom end of the valve stem (5) is fixedly connected to a slider (6), and a valve core assembly is arranged in the inner cavity of the valve body (1).

2. A valve with a leakage rate control function according to claim 1, characterized in that: The valve core assembly comprises a movable rod (7) arranged in the valve body (1); the cross section of the movable rod (7) is T-shaped; a spring (8) is sleeved between the side wall of the movable rod (7) and the inner cavity of the valve body (1); a valve stem insert (9) is installed near the bottom end of the side wall of the movable rod (7); a sealing member is arranged in the valve stem insert (9).

3. A valve with a leakage rate control function according to claim 2, characterized in that: The sealing element comprises a valve stem bushing (10) arranged in a valve stem insert cylinder (9), an insert (11) is assembled in the valve stem bushing (10), and the bottom end surface of the insert (11) is conical.

4. A valve with a leakage rate control function according to claim 3, characterized in that: The side wall of the valve stem bushing (10) is distributed in a stepped manner, and the valve stem bushing (10) abuts against the inner wall of the valve stem insert (9).

5. The valve with leakage rate control function according to claim 1, characterized in that: The top end surface of the valve body (1) is distributed in a stepped manner, and a gasket (12) is installed between the valve body (1) and the slider seat (3).

6. A valve with a leakage rate control function according to claim 5, characterized in that: A diaphragm (13) is installed between the valve body (1) and the slider seat (3) and above the gasket (12).

7. A valve with a leakage rate control function according to claim 1, characterized in that: A force-bearing hole (14) is provided on the side wall of the rotating handle (4).

8. The valve with leakage rate control function according to claim 3, characterized in that: The bottom of the inner cavity of the valve body (1) is provided with a drainage groove (15), and the bottom ends of the valve stem insert (9) and the valve stem bushing (10) are both in contact with the drainage groove (15).

9. A valve with a leakage rate control function and a control method thereof according to claim 3, characterized in that: The valve stem insert (9) and the valve stem bushing (10) are interference fit or clearance fit, with the interference amount being 0 to 0.08 mm and the clearance amount being 0 to +0.05 mm.

10. A method for controlling a valve with a leakage rate control function, according to the valve with a leakage rate control function according to any one of claims 1 to 9, characterized in that: The control method comprises the following steps: S1: Turn the rotary handle (4) clockwise to drive the valve stem (5) to rotate, and the valve stem (5) drives the slider (6) to move downward, and the diaphragm (13) is deformed downward by force, driving the valve core assembly to operate; S2: The slider (6) drives the movable rod (7) to move downward through the diaphragm (13), and the movable rod (7) drives the valve stem insert (9) and the valve stem bushing (10) to move downward. At the same time, the spring (8) is compressed to close and seal the valve. S3: When the valve needs to be opened, the rotary handle (4) is turned counterclockwise to drive the valve stem (5) to rotate, and the valve stem (5) drives the slider (6) to move upward, and the rebound force of the spring (8) drives the movable rod (7) to push up the diaphragm (13), and the valve core assembly is lifted upward; S4: According to the degree of loosening of the valve stem (5) driven by the rotating handle (4), the valve stem insert (9) and the valve stem bushing (10) move upwards in coordination with the resilience of the spring (8), thereby increasing the gap between the valve stem insert (9) and the drainage groove (15), and thus opening the valve.

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