Valve element convenient to replace and machining process thereof

Abstract

The valve element convenient to replace comprises a valve body, the valve body and an upper rod sleeve are connected and fixed through a locking sleeve, an upper valve rod is connected into the upper rod sleeve in a screwed mode, a handle is arranged at the top end of the upper valve rod, a sliding block base is connected to the bottom end of the upper valve rod in a screwed mode, and the sliding block base is provided with a sliding block. A diaphragm is arranged between the upper rod sleeve and the valve body, a gasket is connected to the bottom of the diaphragm in a pressed mode, a lower valve rod is arranged in the valve body, a spring is connected to the lower valve rod in a sleeved mode, an embedded cylinder is connected to the bottom end of the lower valve rod in a sleeved mode, a lining is arranged in the embedded cylinder, an insert is connected into the lining in an embedded mode, and a guiding piece is arranged at the bottom end in the valve body. And the bottom end of the spring is pressed on the guide piece. The valve has the advantages that the sealing performance is high, when the valve is closed, the spring is compressed under pressure, and when oscillation is generated, the spring has an anti-loosening effect, so that the sealing performance is improved, leakage is avoided, the service life is prolonged, and the bush is prevented from cracking.

Description

Technical Field

[0001] The present invention relates to the field of valve technology, and more particularly to a valve core that is easy to replace and a processing technology thereof. Background Art

[0002] The semiconductor material MO source is stored and transported in a source bottle. The source bottle valve needs to be welded at the outlet end of the source bottle, so that the valve body is integrated with the round bottle and cannot be disassembled. However, the source bottle is reusable and only needs to be recycled and cleaned by the source bottle manufacturer before it can be used. It was found at the source bottle production and use end that conventional valves often have internal leakage, and it is very troublesome to replace accessories. Sometimes the valve will be scrapped due to replacement of accessories, which increases working hours and costs. The source bottle will vibrate during transportation, which requires the valve on the source bottle to have a good anti-loosening effect to prevent leakage of MO source materials. High temperature insulation of 115°C is required in the source bottle cleaning process, so this type of valve is also required to be resistant to high temperatures.

[0003] However, the existing valve core still has the following defects:

[0004] 1. The valve core collapses after repeated use;

[0005] 2. Under high temperature conditions of 115℃, after keeping warm for a certain period of time and cooling naturally, there is internal leakage;

[0006] 3. The valve core assembly interference is large, resulting in cracks after assembly, affecting the sealing and service life.

[0007] Therefore, a valve core that is easy to replace and a processing technology thereof are now proposed. Summary of the invention

[0008] In order to overcome the above-mentioned defects of the prior art, the present invention provides a valve core that is easy to replace and a processing technology thereof to solve the problems raised in the above-mentioned background technology.

[0009] To achieve the above object, the present invention provides the following technical solutions: a valve core that is easy to replace, comprising a valve body, a locking sleeve, an upper rod sleeve and a handle, wherein the valve body and the upper rod sleeve are connected and fixed by the locking sleeve, an upper valve stem is screwed into the upper rod sleeve, a handle is provided at the top of the upper valve stem, a slider seat is screwed at the bottom of the upper valve stem, a diaphragm is provided between the upper rod sleeve and the valve body, and a gasket is pressed at the bottom of the diaphragm;

[0010] A lower valve stem is arranged in the valve body, a spring is sleeved on the lower valve stem, an embedded cylinder is sleeved on the bottom end of the lower valve stem, a bushing is arranged in the embedded cylinder, and an insert is embedded in the bushing.

[0011] The bushing and the insert are clearance-fitted, with the clearance being 0 to +0.05 mm. The roughness of the sealing surface connecting the insert and the bushing is Ra≤0.7, and the bushing is made of PCTFE material.

[0012] Preferably, a guide is provided at the bottom end of the valve body, the bottom end of the spring is pressed onto the guide, the guide is coaxially arranged with the embedded cylinder, and the outer wall of the embedded cylinder is slidably connected to the guide.

[0013] Preferably, protrusions are symmetrically arranged on the top of the insert cylinder, a screw groove is opened on the inner wall of the top end of the insert cylinder, and the bottom end of the lower valve stem is spirally connected to the screw groove.

[0014] Preferably, a communication port is provided at the bottom end of the interior of the valve body, and the bushing and the insert are arranged in cooperation with the communication port.

[0015] Preferably, the gasket is made of SS316L and has a PTFE coating on its surface.

[0016] A valve core processing technology comprises the following steps:

[0017] S1: Precisely process the bushing and insert to the design size tolerance;

[0018] S2: The sealing surface connecting the bottom of the insert and the bushing is precisely processed to obtain the required roughness;

[0019] S3: Use special tooling to control the assembly process of the valve core to ensure that the installation height and concentricity meet the requirements;

[0020] S4: Perform a long-term heat preservation test on the valve core in a high temperature environment to verify its temperature resistance.

[0021] Preferably, the insulation test condition in S4 is to tighten the handle with a torque of 5 N / m to close the valve, keep it at a high temperature of 115 degrees Celsius for 12 hours, and perform a helium internal leakage test with a test standard of 4.0*10-10Pa m 3 / s.

[0022] Preferably, the heat preservation test step in S4 is:

[0023] First, put the assembled valve core into a high temperature box at 115℃ for 12 hours, observe the changes in the valve core, and determine the cracking factors of the bushing;

[0024] Secondly, verify separately according to the factors that may cause the bushing to crack;

[0025] Then, based on the verification results, the cracking factors are determined and the valve core is improved;

[0026] Finally, the sealing effect and service life of the improved valve core are verified, and if qualified, the valve core is produced according to the improved process.

[0027] Technical effects and advantages of the present invention:

[0028] 1. The connection between the valve body and the upper rod sleeve is sealed by a gasket, which can improve the overall sealing of the valve. When the valve is closed, the spring is compressed under pressure. When vibration occurs, the valve compresses the spring when it is closed. When the spring is compressed, there is a pre-tightening force, which can effectively seal and has an anti-loosening effect, thereby improving the sealing and avoiding leakage;

[0029] 2. This processing technology analyzes and tests the factors that cause collapse and can determine the final factors, so as to make more accurate improvements to the valve core accessories. The valve core produced according to the improved data can avoid bushing collapse, internal leakage and bushing cracking, thereby improving the sealing and service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0031] Figure 2 It is a schematic diagram of the cross-sectional structure of the present invention.

[0032] Figure 3 It is a schematic diagram of the guide member and the nested matching structure of the present invention.

[0033] Figure 4 It is a schematic diagram of the cross-sectional structure of the connection between the lower valve stem, the embedded cylinder, the bushing and the insert of the present invention.

[0034] Figure 5 It is a schematic diagram of the cross-sectional structure of the connection between the insert sleeve, the bushing and the insert of the present invention.

[0035] Figure 6 It is a schematic diagram of the bushing collapse caused by the initial interference state between the bushing and the insert sleeve of the present invention.

[0036] Figure 7 This is a schematic diagram of test results after improving the dimensions of the bushing and the insert according to the present invention.

[0037] Figure 8 This is a diagram for measuring and analyzing the dimensions of three matching parts of the present invention.

[0038] Fig. 9 The diagram is a diagram showing the improvement results of the bushing and insert dimensions of the present invention.

[0039] Fig.10 It is a schematic diagram of the valve core of the present invention in a qualified state after testing.

[0040] The accompanying drawings are marked as follows: 1. valve body; 2. locking sleeve; 3. upper rod sleeve; 4. handle; 5. upper valve stem; 6. slider seat; 7. lower valve stem; 8. gasket; 9. embedded cylinder; 10. bushing; 11. insert; 12. diaphragm; 13. guide; 14. spring. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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. 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.

[0042] As attached Figure 1-5 A valve core that is easy to replace is shown, comprising a valve body 1, a locking sleeve 2, an upper rod sleeve 3 and a handle 4. The valve body 1 and the upper rod sleeve 3 are connected and fixed by the locking sleeve 2. An upper valve stem 5 is screwed into the upper rod sleeve 3. A handle 4 is provided at the top of the upper valve stem 5. A slider seat 6 is screwed at the bottom of the upper valve stem 5. A diaphragm 12 is provided between the upper rod sleeve 3 and the valve body 1, and a gasket 8 is crimped at the bottom of the diaphragm 12.

[0043] A lower valve stem 7 is arranged in the valve body 1 , a spring 14 is sleeved on the lower valve stem 7 , an embedded tube 9 is sleeved on the bottom end of the lower valve stem 7 , a bushing 10 is arranged in the embedded tube 9 , and an insert 11 is embedded in the bushing 10 .

[0044] The bushing 10 and the insert 9 are clearance-fitted, and the clearance is 0 to +0.05 mm. The roughness of the sealing surface between the insert 9 and the bushing 10 is Ra≤0.7. The bushing 10 is made of PCTFE material.

[0045] A communication port is disposed at the bottom end of the valve body 1 , and the bushing 10 and the insert 11 are disposed in cooperation with the communication port.

[0046] In specific implementation, by turning the handle 4 clockwise, the upper valve stem 5 and the slider seat 6 are threadedly matched, so that the slider seat 6 moves downward to squeeze the diaphragm 12, so that the middle of the diaphragm 12 presses down on the top of the lower valve stem 7, so that the spring 14 is compressed under the support of the guide 13, and the valve plug composed of the bottom insert 9, the bushing 10 and the insert 11 presses down on the bottom end of the valve body 1 to achieve the closing and sealing of the valve;

[0047] By rotating the handle 4 counterclockwise, the upper valve stem 5 moves upward, and under the rebound of the spring 14, the lower valve stem 7 moves upward, and the diaphragm 12 recovers, so that the gap between the valve plug and the valve body 1 gradually increases, so that the communication port is opened, and the valve is opened.

[0048] A guide 13 is disposed at the bottom end of the valve body 1 , and the bottom end of the spring 14 is pressed onto the guide 13 . The guide 13 is coaxially disposed with the insert cylinder 9 , and the outer wall of the insert cylinder 9 is slidably connected with the guide 13 .

[0049] The top of the embedded cylinder 9 is symmetrically provided with protrusions, the inner wall of the top end of the embedded cylinder 9 is provided with a screw groove, and the bottom end of the lower valve stem 7 is spirally connected to the screw groove to facilitate the connection between the embedded cylinder 9 and the lower valve stem 7.

[0050] Specifically, the lower valve stem 7 serves as a guide member for connection; the insert 9 enables the bushing 10 to be installed and fixed in the insert 9 to prevent excessive extrusion; the bushing 10 serves as a key sealing material for the connecting port; the insert 11 presses the bushing 10 in a fixed position to prevent extrusion, and also serves as a limiter; the guide 13 serves to play a concentric role when the valve core moves as a whole.

[0051] The gasket 8 is made of SS316L and has a PTFE coating on the surface, which can effectively prevent the same material from biting after compression, and at the same time play an overall sealing role to improve the sealing performance. It can be replaced each time it is used to ensure the sealing requirements for external leakage.

[0052] A valve core processing technology comprises the following steps:

[0053] S1: Precisely process the bushing 10 and the insert 9 to within the design size tolerance range;

[0054] Specifically, Figure 6 , the bushing 10 and the insert cylinder 9 are connected by interference fit, as shown in Table 1 below. After the two are assembled, the bushing 10 is extruded and produces particles and burrs. After the switch life, the bushing 10 and the valve body 1 are squeezed up and down, causing the bushing 10 to collapse;

[0055] The size of the insert 9 was changed according to the collapse phenomenon. After the change, the bushing 10, the insert 9 and the insert 11 were connected and tested. The test conditions were: the valve was opened and closed with a pressure of 75PSIG. After 100 times of life, the valve was observed under a magnifying glass with a magnification of 10 times. The test results are as follows.

[0056] Table 1 Change data of insert and bushing

[0060] Test results such as Figure 7 It can be seen that after the change, the bushing 10 is not extruded, and no particles or burrs are generated; after the change, the bushing 10 will not be extruded after the life test.

[0061] S2: Precision machining is performed on the sealing surface where the bottom of the insert 9 and the bushing 10 are connected, so as to obtain the required roughness;

[0062] Specifically, by further improving the roughness of the sealing surface, it is determined that the roughness of the sealing surface between the insert 9 and the bushing 10 is Ra≤0.7, and the valve core with improved roughness is tightened with a handle valve stem at a torque of 5N / m, so that the valve is in a closed state, and kept at a high temperature of 115 degrees Celsius for 12 hours, and a helium internal leakage test is performed, and the test standard is 4.0*10-10Pa m 3 / s. In the test results, the internal leakage test was qualified after tightening the assembly with 5N / m. After 12 hours of high temperature, internal leakage may occur in the high temperature state and the normal temperature state. After the high temperature, the helium test was qualified when the valve was closed again with 5N / m.

[0063] S3: Use special tooling to control the assembly process of the valve core to ensure that the installation height and concentricity meet the requirements;

[0064] S4: Perform a long-term heat preservation test on the valve core in a high temperature environment to verify its heat resistance. The heat preservation test conditions are: tighten the handle 4 with a torque of 5N / m to close the valve, keep it at a high temperature of 115 degrees Celsius for 12 hours, and perform a helium internal leakage test. The test standard is 4.0*10-10Pa m 3 / s.

[0065] The heat preservation test steps in S4 are:

[0066] First, put the assembled valve core into a high temperature box at 115℃ for 12 hours, observe the changes of the valve core, and determine the cracking factor of the bushing 10;

[0067] Specifically, PCTFE cracking was found after the valve core was exposed to a high temperature of 115 degrees Celsius for 12 hours; 5 valve cores were assembled, and 2 of them were cracked; after the high temperature of 115115℃ for 12 hours, the valve stem insert under the rear valve core protruded, and 5 valve cores were assembled, and one of them protruded;

[0068] The following cracking factors were obtained:

[0069] 1. When assembling the valve core, the pressure of the tooling is too large, causing the valve seat to crack quickly during assembly.

[0070] Cracks appear after high temperature;

[0071] 2. When assembling the valve core, the force of the tooling is too large, which will cause cracks during assembly;

[0072] 3. PCTEF material will crack at a high temperature of 115 degrees Celsius for 12 hours;

[0073] 4. The valve core assembly interference is large, resulting in cracks after assembly.

[0074] Secondly, according to the possible cracking factors of the bushing 10, verification is carried out separately;

[0075] Specifically, factor 1 and factor 2 are verified in the following way:

[0076] Control the installation height, ①, 0.17-0.18 ②, 0.19-0.25, press the valve core 5pcs each;

[0077] Put both valve cores in a high temperature box and keep them at 115 degrees Celsius for 12 hours, then take them out to observe whether there is any cracking;

[0078] Verification results: After the valve core is assembled, no cracks will occur at room temperature;

[0079] Installation height, ①, 0.17-0.18 ②, 0.19-0.25, all have cracks after high temperature;

[0080] Installation height, ①, 0.17-0.18, tested 5 pieces, 3 pieces had cracks;

[0081] Installation height, ②, 0.19-0.25, tested 5 pieces, 2 pieces had cracks;

[0082] The conclusion is: cracks will not occur at room temperature, but will occur after high temperature.

[0083] Factor 3 is verified by:

[0084] The bushing 10 is placed in a high temperature of 115 degrees Celsius for 12 hours according to the three states of bushing 10 and insert 9 connection, bushing 10 and insert 11 connection, and bushing 10 alone, and then taken out and observed under a 10x microscope to see if there are cracks;

[0085] Test results: There are no cracks in the three states. In the first and second states, the bushing 10 is displaced after high temperature.

[0086] Factor 4 was verified by measuring the dimensions of the three mating parts (bushing 10, insert 9 and insert 11) and analyzing them. As shown in Figure 8, it was concluded that whether the interference fit was reasonable needed further testing, and whether the insert 11 and bushing 10 would crack due to excessive temperature after assembly;

[0087] Then the interference is adjusted, as shown in Figure 9, it can be concluded that after reducing the interference, the bushing 10 will not crack after high temperature, thereby determining that the bushing 10 and the insert 9 are clearance-fitted, and the clearance is 0 to +0.05 mm.

[0088] Then, based on the verification results, the cracking factors are determined and the valve core is improved.

[0089] Finally, the sealing effect and service life of the improved valve core are verified, and if qualified, the valve core is produced according to the improved process.

[0090] Specifically, Fig.10 Obtain the qualified status diagram of the final product after testing.

[0091] Finally, a few points should be explained: First, in the description of the present invention, it should be noted that, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, which may refer to mechanical connection or electrical connection, or internal communication between two components, or direct connection. "upper", "lower", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may change;

[0092] Secondly: In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0093] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A leak-proof precision valve core, comprising a valve body (1), a locking sleeve (2), an upper rod sleeve (3) and a handle (4), Features: The valve body (1) and the upper rod sleeve (3) are connected and fixed by a locking sleeve (2); an upper valve stem (5) is screwed into the upper rod sleeve (3); a handle (4) is provided at the top end of the upper valve stem (5); a slider seat (6) is screwed at the bottom end of the upper valve stem (5); a diaphragm (12) is provided between the upper rod sleeve (3) and the valve body (1); a gasket (8) is pressed at the bottom of the diaphragm (12); A lower valve stem (7) is arranged in the valve body (1), a spring (14) is sleeved on the lower valve stem (7), an embedded cylinder (9) is sleeved on the bottom end of the lower valve stem (7), a bushing (10) is arranged in the embedded cylinder (9), and an insert (11) is embedded in the bushing (10); The bushing (10) and the insert (9) are clearance-fitted, with the clearance amount being 0 to +0.05 mm. The roughness of the sealing surface where the insert (9) and the bushing (10) are connected is Ra≤0.7, and the bushing (10) is made of PCTFE material.

2. A leak-proof precision valve core according to claim 1, Features: A guide member (13) is provided at the bottom end of the valve body (1), the bottom end of the spring (14) is pressed onto the guide member (13), the guide member (13) is coaxially arranged with the embedded cylinder (9), and the outer wall of the embedded cylinder (9) is slidably connected to the guide member (13).

3. A leak-proof precision valve core according to claim 1, Features: The top of the embedded cylinder (9) is symmetrically provided with protrusions, the inner wall of the top end of the embedded cylinder (9) is provided with a screw groove, and the bottom end of the lower valve stem (7) is spirally connected to the screw groove.

4. A leak-proof precision valve core according to claim 1, Features: A communication port is provided at the bottom end of the valve body (1), and the bushing (10) and the insert (11) are arranged in cooperation with the communication port.

5. A leak-proof precision valve core according to claim 1, Features: The gasket (8) is made of SS316L and has a PTFE coating on its surface.

6. A valve core processing technology, Features: Includes steps: S1: Precisely process the bushing (10) and the insert (9) to within the design dimensional tolerance range; S2: Precision machining is performed on the sealing surface where the bottom of the insert (9) and the bushing (10) are connected to obtain the required roughness; S3: Use special tooling to control the assembly process of the valve core to ensure that the installation height and concentricity meet the requirements; S4: Perform a long-term heat preservation test on the valve core in a high temperature environment to verify its temperature resistance.

7. A valve core processing technology according to claim 6, Features: The insulation test condition in S4 is to tighten the handle (4) with a torque of 5 N / m to close the valve, keep it at a high temperature of 115 degrees Celsius for 12 hours, and perform a helium internal leakage test with a test standard of 4.0*10-10Pa m 3 / s.

8. A valve core processing technology according to claim 7, Features: The heat preservation test steps in S4 are: First, the assembled valve core is placed in a high temperature box at 115°C for 12 hours, and the changes in the valve core are observed to determine the cracking factor of the bushing (10); Secondly, according to the possible cracking factors of the bushing (10), verification is performed separately; Then, based on the verification results, the cracking factors are determined and the valve core is improved; Finally, the sealing effect and service life of the improved valve core are verified, and if qualified, the valve core is produced according to the improved process.

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