High-purity ball valve

Abstract

The high-purity ball valve comprises a valve body, a valve ball and a valve rod, the valve body is provided with a hollow valve cavity, the valve ball is rotatably arranged in the valve cavity so as to open or close the valve, the valve rod is movably connected to the valve ball, the valve rod is provided with a first seal and a second seal in the axial direction, and the first seal and the second seal are arranged in the valve cavity. A first static conduction device is arranged between the first seal and the second seal, and a second static conduction device is arranged between the valve rod and the valve ball. Multiple seals are arranged on the valve rod, and the axial sealing effect of the valve rod is guaranteed. Static electricity conduction devices are arranged between the valve rod and the valve ball and between the valve rod and the valve body respectively, so that the valve ball, the valve rod and the valve body form a conductive channel, static electricity generated by rotating friction between the valve seat and the valve ball and rotating friction between the valve rod and the sealing piece is transmitted to the outside of the valve to be grounded, and electrostatic adsorption is prevented. The sealing surface of the valve ball and the valve seat adopts a reducing spherical surface structure, so that the inner side of the valve seat and the valve ball are sealed more tightly. An auxiliary support is arranged below the valve ball to prevent the valve seat from being excessively abraded due to overweight of the valve ball.

Description

TECHNICAL FIELD

[0001] The utility model relates to the application field of biological medicine and semiconductor high purity, and specifically relates to a high purity ball valve. BACKGROUND

[0002] The high purity ball valve is a valve widely used in high purity fluid conveying systems of energy chemical industry, semiconductor electronics, food processing, pharmaceutical and biotechnology, and has high requirements for sealing and cleanliness. The stem seal of the high purity ball valve mostly adopts PTFE packing seal. With the passage of time, the PTFE packing is prone to relaxation, which causes leakage at the stem. In the opening and closing process of the valve, static electricity is easily generated between the valve ball and the valve seat, and between the stem and the packing. The static electricity can cause small particles or contaminants to adhere to the surface of the valve, which is extremely unfavorable in the semiconductor, biological medicine and other industries. These adhered particles can be transferred to the fluid in the subsequent process, causing product contamination and affecting product quality. In addition, for large-size high purity ball valves, the valve ball is relatively heavy, and frequent rotation of the valve ball can increase the wear of the lower half of the valve seat. Over time, the sealing performance of the valve is affected, and the service life is greatly reduced. The larger the size of the valve, the greater the torque when the valve rotates, which not only wastes time and effort, but also affects the operation experience. SUMMARY

[0003] The utility model discloses a high purity ball valve, which solves the technical problems of the existing high purity ball valve, such as easy leakage at the stem, easy static adsorption, easy wear of the valve seat and large torque.

[0004] To achieve the above-mentioned purpose, the utility model provides a high purity ball valve, which comprises a valve body, a valve ball and a valve stem. The valve body has a hollow valve cavity. The valve ball is rotatably arranged in the valve cavity to open or close the valve. The valve stem is movably connected to the valve ball. The valve stem is provided with a first seal and a second seal in its axial direction. A first static electricity conduction device is arranged between the first seal and the second seal. A second static electricity conduction device is arranged between the valve stem and the valve ball.

[0005] Further, the valve stem is provided with a first seal and a second seal. The first seal is arranged on the radial protrusion of the valve stem. The second seal is arranged above the first seal. The first seal and the second seal form the first seal and the second seal in the axial direction of the valve stem.

[0006] Further, the protrusion is provided with a wedge surface on the side adjacent to the first seal. The first seal is provided with an inner tapered surface matched with the wedge surface. The included angle formed by the inner tapered surface is smaller than the included angle formed by the wedge surface.

[0007] Further, a valve rod channel is arranged on the valve body, a packing group is arranged in the valve rod channel, the packing group is above the second sealing element, and the packing group is limited in the valve rod channel by a guide compression compensation assembly.

[0008] Further, the guide compression compensation assembly comprises a compression sleeve, a disc spring and a compression plate, the disc spring is arranged on the compression sleeve, and the compression plate is arranged on the disc spring and axially compresses the disc spring.

[0009] Further, a positioning plate is arranged on the valve rod, the positioning plate rotates under the driving of the valve rod, a positioning pin is arranged on the valve body, and the positioning pin limits the rotation of the positioning plate.

[0010] Further, a lock plate is connected to the positioning pin, and the lock plate is used to form a locking state with the positioning plate.

[0011] Further, valve seats are further arranged at both ends of the valve body, a sealing spherical surface is arranged on the side of the valve seat facing the valve ball, and the diameter of the sealing spherical surface is greater than the diameter of the valve ball.

[0012] Further, the valve seat is limited in the valve cavity by an end connector connected to the end of the valve body, and a valve body sealing element is arranged between the end connector and the valve body.

[0013] Further, the valve cavity further comprises a cylindrical hole at the bottom, and the bottom of the valve ball is provided with a support.

[0014] Compared with the prior art, the beneficial effects of the utility model are that multiple seals are arranged on the valve rod to guarantee the axial sealing effect of the valve rod. Meanwhile, electrostatic conduction devices are arranged between the valve rod and the valve ball and between the valve rod and the valve body, so that the valve ball, the valve rod and the valve body form a conductive channel, the static electricity generated in the valve is transmitted to the outside of the valve body, static adsorption is prevented, and the entry of tiny particles into the valve cavity is reduced. The valve ball and the valve seat sealing surface adopt a stepped spherical surface structure, so that the inner side of the valve seat and the valve ball are more tightly sealed. An auxiliary support is arranged below the valve ball to prevent excessive wear of the valve seat caused by excessive weight of the valve seat. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a whole schematic view of the utility model;

[0016] Figure 2 It is a top view of the utility model;

[0017] Figure 3 It is Figure 2 a sectional view in direction A-A;

[0018] Figure 4 It is Figure 3 a local enlarged view at B;

[0019] Figure 5 is a structural schematic view of a valve body;

[0020] Figure 6 is a structural schematic view of a valve stem;

[0021] Figure 7 is a structural schematic view of a first sealing member;

[0022] Figure 8 is a structural schematic view of a valve seat;

[0023] In the figure, 1, valve body; 2, valve ball; 3, valve seat; 4, end fitting; 5, valve body sealing member; 6, bolt; 7, nut; 8, valve stem; 9, packing group; 10, pressure sleeve; 11, disc spring; 12, pressure plate; 13, inlet; 14, outlet; 15, valve stem passage; 16, protrusion; 17, positioning plate; 18, valve cavity; 19, first sealing member; 20, second sealing member; 21, cylindrical hole; 22, steel ball; 23, support; 24, locking plate; 25, positioning pin; 26, snap ring; 27, connecting bolt; 28, fastening bolt; 29, handle; 30, upper part; 31, lower part; 32, spring; 33, inner conical surface; 34, sealing spherical surface; 35, annular groove; 36, first side hole; 37, second side hole; 38, washer; 39, retaining ring; 40, guide boss; 41, connecting part; 42, positioning part. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but merely represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor fall within the scope of the present application.

[0026] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0027] In the description of the utility model, it needs to explain, the term "center", "upper", "lower", "left", "right", "top", "bottom", "inner", "outer" and so on indicate the orientation or position relation is based on the orientation or position relation shown in the drawing, or it is the orientation or position relation that the utility model uses when usually placed, only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element indicated must have a particular orientation, with a particular orientation structure and operation, therefore can not be understood as the limitation of the utility model.

[0028] In addition, the terms "horizontal", "vertical" and the like do not mean that the components must be absolutely horizontal or hanging, but can be slightly inclined. For example, "horizontal" only means that it is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0029] In the description of the utility model, it also needs to explain that, unless otherwise specified and limited, the terms "set", "install", "connect", "connect" should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium, can be the communication inside two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0030] Some embodiments of the utility model will be described in detail below with reference to the drawings.

[0031] For details, see the drawings Figures 1-3 The utility model discloses a high purity ball valve, including valve body 1, valve ball 2, valve stem 8. Valve body 1 has hollow valve cavity 18, and valve cavity 18 is through inlet 13 and outlet 14. Valve ball 2 is rotatably arranged in valve cavity 18, and valve ball 2 can be installed in valve body 1 in the way of side loading or upper loading, in this embodiment, valve body 1 is integrally cast into shape, and valve ball 2 is installed in valve body 1 in the way of side loading.

[0032] Valve stem 8 is movably connected with valve ball 2, and valve stem 8 is cylindrical, including upper part 30 and lower part 31, see the drawings Figure 6As shown, the lower part 31 is used to enter the connecting groove on the valve ball 2. The valve stem 8 can be axially rotated to drive the valve ball 2 to switch between the open and closed positions. When the valve ball 2 is in the open position, the medium can flow from the inlet 13 to the outlet 14, and when the valve ball 2 is in the closed position, the medium is blocked and cannot flow. The valve stem 8 is provided with a first seal and a second seal in its axial direction, and further, a radial protrusion 16 is arranged between the upper part 30 and the lower part 31 of the valve stem 8, and the first seal 19 is arranged on the protrusion 16, which forms a first seal in the axial direction of the valve stem 8. The upper part 30 of the valve stem 8 is also provided with an annular groove 35, and the second seal 20 is arranged in the annular groove 35, which forms a second seal in the axial direction of the valve stem 8.

[0033] Preferably, the first seal 19 and the protrusion 16 form a wedge-shaped seal, and the specific structure can be seen from the accompanying Figure 6 and 7 . The protrusion 16 has a wedge surface 28 on the side facing the first seal 19, and the first seal 19 has an inner tapered surface 33 adjacent to the inner side of the protrusion 16. The wedge surface 28 forms an included angle α, and the inner tapered surface 33 forms an included angle β, and α>β. In one embodiment, the included angle β is 80°, and the included angle α is 90°. The contact diameter of the first seal 19 with the valve body 1 is D1, and the contact outer diameter with the valve stem 8 is d2, and D1>d2. The wedge surface 28 and the inner tapered surface 33 have an angle difference, which is beneficial to sealing. When the pipeline system is under pressure, the medium under pressure will generate an upward thrust on the valve stem 8, and the valve stem 8 will press the first seal 19, thereby forming a first seal at this position. Within the allowable pressure range of the valve, the larger the system pressure, the better the wedge-shaped sealing effect.

[0034] One aspect of the utility model lies in eliminating electrostatic adsorption caused by rotation of the valve ball or the valve stem. Specifically, a first electrostatic conduction device is arranged between the first seal and the second seal, and a second electrostatic conduction device is arranged between the valve stem 8 and the valve ball 2. Referring to the accompanying Figure 6 , the valve stem 8 is provided with a first side hole 36 and a second side hole 37. The first side hole 36 is arranged on the upper part 30 of the valve stem 8 and located between the annular groove 35 and the protrusion 16, and the second side hole 37 is located on the lower part 31 of the valve stem 8. The first electrostatic conduction device is arranged in the first side hole 36, and the second electrostatic conduction device is arranged in the second side hole 37. The first electrostatic conduction device and the second electrostatic conduction device can also be arranged on the valve body 1 or the valve ball 2. The electrostatic conduction device includes a steel ball 22 and a spring 32, and the specific structure can be seen from the accompanying Figure 3 and 4The steel ball 22 is located at the front end of the spring 32. The first and second electrostatic conduction devices form a conductive channel between the valve body 1, the valve ball 2, and the valve stem 8. A grounded wire can be installed on the valve body 1 to transfer static electricity from inside the valve and prevent electrostatic adsorption. The first electrostatic conduction device is located between the first seal 19 and the second seal 20 to prevent tiny particles generated by the friction between the steel ball 8 in the first electrostatic conduction device and the valve body 1 during valve stem 8 rotation from falling into the valve cavity 18.

[0035] See appendix Figure 5 As shown, the valve body 1 includes a valve stem passage 15 for receiving the valve stem 8, and the valve stem passage 15 extends through the valve cavity 18. The lower part 31 of the valve stem 8 is connected to the valve ball 2, and the upper part 30 extends outside the valve stem passage 15. A packing assembly 9 is provided in the valve stem passage 15. The packing assembly 9 is V-shaped, made of PTFE, and axially located above the second seal 20. A compression compensation assembly is provided above the packing assembly 9, so that the packing assembly 9 forms a third seal in the axial direction of the valve stem 8, further reducing the leakage risk at the valve stem 8, reducing the friction between the packing assembly and the valve stem 8, and reducing the torque required for the valve stem 8 to rotate the valve ball 2. The compression compensation assembly includes a pressure sleeve 10, a disc spring 11, and a pressure plate 12. See Appendix Figure 3 and 4 The pressure sleeve 10 is located above the packing assembly 9, and the disc spring 11 is located on the pressure sleeve 10. A guide boss 40 extends upward from the inner edge of the pressure sleeve 10, facilitating the guidance of the disc spring 11 and preventing it from tilting. A pressure plate 12 is positioned above the disc spring 11, and is connected to the valve body 1 by fastening bolts 28, holding the disc spring 11 and the pressure sleeve 10 in place. The pressure plate 12 has a certain axial length, facilitating the guidance of the disc spring 11's inner hole, preventing it from deviating, and ensuring more even force distribution. The disc spring 11 is installed face-to-face or back-to-back; this arrangement more effectively compensates for axial clamping force when the packing assembly 9 loosens.

[0036] See appendix Figures 1-2A positioning plate 17 is also provided on the valve stem 8, and the positioning plate 17 is held on the valve stem 8 by an elastic retaining ring 39. The positioning plate 17 includes a circular connecting part 41 and positioning parts 42 symmetrically arranged at both ends of the connecting part 41. The connecting part 41 is provided with a waist-shaped hole that mates with the flat part of the valve stem 8, and the valve stem 8 can drive the positioning plate 17 and the valve stem 8 to rotate together. A handle 29 is provided above the positioning plate 17, and a washer 38 is provided on the handle 29. The washer 38 is connected to the valve stem 8 by a connecting bolt 27, which also limits the handle 29 to the valve stem 8. The handle 29 is used to drive the valve stem 8 to rotate, thereby driving the valve ball 2 to rotate. A positioning pin 25 is provided on the valve body 1. The positioning pin 25 is arranged within the rotation circumference of the positioning part 42 and is used to limit the rotation amplitude of the positioning plate 17, thereby limiting the rotation angle of the valve stem 8, so that the valve switches between the open and closed positions. When the handle 29 is turned to the open position, the positioning part 42 at one end of the positioning plate 17 contacts the positioning pin 25 to prevent the valve ball from being over-opened or over-closed. (See attached...) Figure 2 As shown, when the handle 29 is rotated to the valve closed position, the positioning part 42 at the other end of the positioning plate 17 contacts the positioning pin 25.

[0037] A locking plate 24 is also provided on the positioning pin 25. The locking plate 24 is oblong, with a connecting hole at one end and a locking hole at the other end. The locking plate 24 is fixed to the positioning pin 25 by a retaining ring 26. A locking hole is also provided on the positioning part 42 of the positioning plate 17, as shown in the attached figure. Figure 1 As shown, when the handle 29 is rotated to the valve open position, the locking hole on the positioning plate 17 is aligned with the locking hole on the locking plate 24. Simply locking the two locking holes can prevent accidental rotation of the handle 29.

[0038] A valve seat 3 may also be installed inside the valve body 1. The valve seat 3 is positioned at both ends of the valve body 1, closely attached to the valve ball 2. (See appendix) Figure 8 The valve seat 3 has a sealing spherical surface 34 on the side facing the valve ball 2. The diameter of the sealing spherical surface 34 is larger than the diameter of the valve ball 2, and the diameter D3 of the sealing part on the side of the valve seat 3 is larger than the average diameter D4 of the valve seat sealing surface. This progressive structure allows the valve seat 3 to have initial elastic deformation, resulting in a tighter seal between the inner side of the valve seat 3 and the valve ball 2, while the outer side experiences relatively less elastic deformation, further reducing the rotational torque of the valve ball 2. End connectors 4 are connected to both ends of the valve body 1. The end connectors 4 are connected to both ends of the valve body 1 by bolts 6 and nuts 7, pressing the valve seat 3 against the valve ball 2. A valve body seal 5 is also provided between the end connector 4 and the valve body 1. The valve body seal 5 is located in a groove on the end face of the valve body 1 to provide a seal between the valve body 1 and the end connector 4. The end connector 4 can be made from a valve cover or steel pipe by rail welding or laser welding, thereby reducing manufacturing costs.

[0039] Another aspect of this invention is that it can prevent the valve ball 2 from excessively squeezing and wearing the lower half of the valve seat 3. (See attached document) Figure 3The bottom of the valve ball 2 is provided with a support 23. The support 23 is embedded in a cylindrical hole 21 at the bottom of the valve body 1, the cylindrical hole 21 is located in the valve cavity 18 and coaxial with the center line of the valve ball 2. The height of the support 23 is controlled at about 0.1mm gap between the bottom of the valve ball and the circular table, the support 23 is used to support the valve ball 2, prevent the valve ball 2 from excessive wear of the valve seat 3 caused by excessive weight.

[0040] The basic principle and advantages of the present application are described above. For those skilled in the art, the above examples are only used to illustrate the technical solutions of the present application, but not to limit it. Although the present application has been described in detail with reference to the foregoing examples, those skilled in the art can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features, by reading this specification. Without departing from the concept of the present application, any obvious replacement is within the protection scope of the present application.

Claims

1. A high purity ball valve characterized by, include: The valve body (1), valve ball (2), and valve stem (8) are provided. The valve body (1) has a hollow valve cavity (18). The valve ball (2) is rotatably disposed in the valve cavity (18) to open or close the valve. The valve stem (8) is movably connected to the valve ball (2). The valve stem (8) is provided with a first seal and a second seal in its axial direction. A first electrostatic conduction device is provided between the first seal and the second seal. A second electrostatic conduction device is provided between the valve stem (8) and the valve ball (2).

2. A high purity ball valve according to claim 1, wherein The valve stem (8) is provided with a first seal (19) and a second seal (20). The first seal (19) is disposed on the radial protrusion (16) of the valve stem (8), and the second seal (20) is disposed above the first seal (19). The first seal (19) and the second seal (20) form the first seal and the second seal in the axial direction of the valve stem (8).

3. A high purity ball valve according to claim 2, wherein The protrusion (16) has a wedge surface (28) on one side adjacent to the first seal (19), and the first seal (19) has an inner conical surface (33) that mates with the wedge surface (28). The included angle formed by the inner conical surface (33) is smaller than the included angle formed by the wedge surface (28).

4. A high purity ball valve according to claim 3, wherein The valve body (1) is provided with a valve stem channel (15), and a packing group (9) is provided in the valve stem channel (15). The packing group (9) is located above the second seal (20), and the packing group (9) is limited in the valve stem channel (15) by a guide compression compensation component.

5. A high purity ball valve according to claim 4, wherein The guide clamping compensation assembly includes a pressure sleeve (10), a disc spring (11), and a pressure plate (12). The disc spring (11) is disposed on the pressure sleeve (10), and the pressure plate (12) is disposed on the disc spring (11). The pressure plate (12) axially compresses the disc spring (11).

6. A high purity ball valve according to claim 5, wherein A positioning plate (17) is provided on the valve stem (8), and the positioning plate (17) rotates under the drive of the valve stem (8). A positioning pin (25) is provided on the valve body (1), and the positioning pin (25) limits the rotation of the positioning plate (17).

7. A high purity ball valve according to claim 6, wherein A locking plate (24) is connected to the positioning pin (25), and the locking plate (24) is used to form a locking state with the positioning plate (17).

8. A high purity ball valve according to claim 3, wherein The valve body (1) is also provided with valve seats (3) at both ends. The valve seat (3) has a sealing spherical surface (34) on the side facing the valve ball (2). The diameter of the sealing spherical surface (34) is larger than the diameter of the valve ball (2).

9. A high purity ball valve according to claim 8, wherein The valve seat (3) is defined in the valve cavity (18) by an end connector (4) connected to the end of the valve body (1), and a valve body seal (5) is provided between the end connector (4) and the valve body (1).

10. A high purity ball valve according to any one of claims 1 to 9, wherein The valve ball (2) is provided with a support (23) at its bottom.

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