Back seal guide pre-tightening device for floating ball valve

Abstract

The invention relates to a back-sealing guide pre-tightening device for a floating ball valve, which comprises a valve body and a valve cover connected with the far end of the valve body, a valve cavity is arranged in the valve body, a flow control unit is accommodated in the valve cavity, a valve rod penetrates through the valve cover, the far end of the valve rod is connected with a floating ball in the flow control unit through a connecting block, and the floating ball is connected with the valve cover through the connecting block. The diameter of the connecting block is larger than that of the valve rod, a pressing assembly is arranged at the far end of the valve cover and comprises a first disc spring and a pressing ring, the pressing ring is fixed to the near end of the valve cover, the part, facing the connecting block, of the pressing ring extends out of the valve cover, and one end of the first disc spring abuts against the far end, extending out of the valve cover, of the pressing ring. The other end abuts against the near end of the connecting block. When the medium pressure is low, upward pressure is provided for the connecting block through the first disc spring, so that the sealing surface between the thrust washers and the sealing surface between the thrust washers and the valve cover reach the set sealing specific pressure, and the sealing effect can be guaranteed under any working condition.

Description

Technical Field

[0001] The invention relates to the technical field of ball valves, in particular to a reverse sealing guide pre-tightening device for a floating ball valve. Background Art

[0002] Valves are control components in fluid delivery systems, with functions such as shutoff, regulation, flow diversion, backflow prevention, pressure stabilization, flow diversion or overflow pressure relief. Valves used in fluid control systems come in a wide variety of varieties and specifications, from the simplest shutoff valves to the various valves used in extremely complex automatic control systems.

[0003] Ball valves are also a common valve body on the market. However, the sealed ball valves on the market now, such as the one-piece high-temperature metal sealed ball valve with document number CN211715815U, although the contact part between the valve stem and the valve cover is provided with a shaft sleeve and packing, when the medium pressure is low, the contact part between the valve stem and the valve cover cannot have sufficient sealing pressure ratio, resulting in the sealing effect not meeting expectations. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a reverse seal guide pre-tightening device for a floating ball valve to solve one or more problems in the prior art.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A reverse seal guide pre-tightening device for a floating ball valve comprises a valve body and a valve cover connected to the distal end of the valve body, a valve cavity is provided in the valve body, a flow control unit is accommodated in the valve cavity, a valve stem passes through the valve cover, the distal end of the valve stem is connected to a floating ball in the flow control unit via a connecting block, the diameter of the connecting block is larger than the diameter of the valve stem, a clamping assembly is arranged at the distal end of the valve cover, the clamping assembly comprises a first disc spring and a pressing ring, the pressing ring is fixed at the proximal end of the valve cover, and the pressing ring extends out of the valve cover toward a part of the connecting block, one end of the first disc spring abuts against the distal end of the part of the pressing ring extending out of the valve cover, and the other end abuts against the proximal end of the connecting block.

[0007] Furthermore, extension parts are arranged on both sides of the connecting block, and the other end of the first disc spring abuts against the extension parts.

[0008] Furthermore, the pressing ring is connected to the proximal end of the valve cover through a first fixing member.

[0009] Furthermore, a step hole is opened on the inner side of the valve cover, and the step hole includes a first hole, a second hole, and a third hole from the distal end to the proximal end, the first hole is in sealing contact with the valve stem, the second hole is in clearance fit with the valve stem, and the third hole is slidably connected to the connecting block.

[0010] Furthermore, the clamping assembly also includes a thrust washer arranged between the connecting block and the third hole.

[0011] Furthermore, the clamping assembly also includes a first sleeve sleeved on the side of the connecting block, and the first sleeve is arranged in the gap between the extension part and the third hole.

[0012] Furthermore, a sealing sleeve assembly is arranged between the first hole and the valve stem, and the sealing sleeve assembly includes a second sleeve, a packing, a packing sleeve, and a packing cover which are arranged in the first hole from the proximal end to the distal end, and the packing cover is connected to the distal end of the valve cover through a second fixing member.

[0013] Furthermore, an inlet and an outlet are respectively provided on both sides of the valve body, and the flow control unit includes a floating ball, a front valve seat arranged at the front end of the floating ball, and a rear valve seat arranged at the rear end of the floating ball. A second disc spring is arranged at the front end of the front valve seat, and the rear valve seat is fixed to the valve body by an adjustment ring. The second disc spring is used to support the sealing contact between the inner annular surface of the front valve seat and the outer surface of the floating ball, and the sealing contact between the outer surface of the floating ball and the inner annular surface of the rear valve seat. The through holes in the inlet, front valve seat, floating ball, rear valve seat and outlet are connected to form a flow channel.

[0014] Furthermore, the far end of the valve stem is connected to an actuator.

[0015] Furthermore, the valve cover is connected to the far end of the valve body through a third fixing member.

[0016] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0017] (I) The floating ball valve of the present invention uses an inverted seal guide pre-tightening device. When the medium pressure is low, the first disc spring provides an upward pressure to the connecting block so that the sealing surface between the thrust washers and the sealing surface between the thrust washers and the valve cover reach a set sealing pressure ratio, thereby ensuring the sealing effect under any working conditions.

[0018] (ii) Furthermore, a thrust washer is arranged between the connecting block and the third hole, and the surface of the thrust washer after matching grinding can achieve self-tight sealing and guide the valve stem at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic structural diagram of a reverse seal guide pre-tightening device for a floating ball valve provided in a first embodiment of the present invention is shown.

[0020] Figure 2 The enlarged structural schematic diagram of a reverse seal guide pre-tightening device for a floating ball valve provided in the first embodiment of the present invention is shown at position A.

[0021] Figure 3The enlarged structural schematic diagram of a reverse seal guide pre-tightening device for a floating ball valve provided in the first embodiment of the present invention is shown at B.

[0022] Markings in the accompanying drawings:

[0023] 1. Valve body; 11. Inlet; 12. Outlet; 13. Valve cavity; 131. First through hole; 2. Valve cover; 21. Step hole; 211. First hole; 212. Second hole; 213. Third hole; 22. Sealing sleeve assembly; 221. Second sleeve; 222. Packing; 223. Packing gland; 224. Packing gland; 225. Second fixing piece; 23. Third fixing piece; 3. Valve stem; 31. Connecting block; 311. Extension; 32. Clamping assembly; 321. Thrust washer; 322. First sleeve; 323. First disc spring; 324. Pressing ring; 325. First fixing piece; 4. Flow control unit; 41. Front valve seat; 42. Rear valve seat; 43. Floating ball; 5. Actuator. DETAILED DESCRIPTION

[0024] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, please refer to the attached drawings. It should be noted that the structures, proportions, sizes, etc. illustrated in the attached drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no technical substantive significance. Any modification of the structure, change of the proportion relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0025] In the description of the present invention, the orientations or positional relationships indicated by terms such as “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “top”, “bottom”, “inside”, “outside”, “axial”, “radial”, and “circumferential” are defined as orientations or positional relationships based on those shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] In order to more clearly describe the structure of the above-mentioned inverted seal guide pre-tightening device for a floating ball valve, the present invention defines the terms "distal end" and "proximal end", "front end" and "rear end". Specifically, the "distal end" refers to the end close to the actuator 5, the "proximal end" refers to the end away from the actuator 5, the "front end" refers to the end close to the fluid inlet direction, and the "rear end" refers to the end away from the fluid inlet direction. Figure 1 For example, Figure 1 The lower end of the middle valve cover 2 is the proximal end. Figure 1The upper end of the middle valve cover 2 is the distal end. Figure 1 The right side of the middle valve body 1 is the front end. Figure 1 The left side of the middle valve body 1 is the rear end.

[0027] Embodiment 1

[0028] Please refer to Figure 1 and Figure 2 A reverse seal guide pre-tightening device for a floating ball valve comprises a valve body 1 and a valve cover 2 connected to the distal end of the valve body 1, a valve cavity 13 is provided in the valve body 1, a first through hole 131 is provided at the distal end of the valve cavity 13 for a part of the valve cover 2 to be inserted, a flow control unit 4 is accommodated in the valve cavity 13, a valve stem 3 passes through the valve cover 2, a distal end of the valve stem 3 is connected to a floating ball 43 in the flow control unit 4 through a connecting block 31, a diameter of the connecting block 31 is larger than a diameter of the valve stem 3, a clamping assembly 32 is arranged at the distal end of the valve cover 2, the clamping assembly 32 comprises a first disc spring 323 and a pressing ring 324, the pressing ring 324 is fixed at the proximal end of the valve cover 2, and the pressing ring 324 extends out of the valve cover 2 toward a part of the connecting block 31, one end of the first disc spring 323 abuts against the distal end of the part of the pressing ring 324 extending out of the valve cover 2, and the other end abuts against the proximal end of the connecting block 31.

[0029] The specific structure of the clamping assembly 32 and the valve cover 2 is described below:

[0030] Please refer to Figure 2 Furthermore, the connecting block 31 is provided with extensions 311 on both sides, the other end of the first disc spring 323 abuts against the extension 311, the extension 311, the valve cover 2, and the pressing ring 324 extend out of the valve cover 2 to form a groove (not marked in the figure), and the groove is used to provide a deformation space for the first disc spring 323 to prevent the first disc spring 323 from deforming excessively. The initial sealing specific pressure of the sealing surface between the thrust washers 321 and the sealing surface between the thrust washers 321 and the valve cover 2 is given by the first disc spring 323.

[0031] Please refer to Figure 2 Further, the pressing ring 324 is connected to the proximal end of the valve cover 2 through a first fixing member 325. Preferably, the first fixing member 325 includes a hexagon socket screw and a locking washer, and the hexagon socket screw passes through the locking washer and the pressing ring 324 and is threadedly connected to the valve cover 2.

[0032] Please refer to Figure 1 and Figure 3Furthermore, a step hole 21 is formed on the inner side of the valve cover 2 along the axis, and the step hole 21 includes a first hole 211, a second hole 212, and a third hole 213 from the distal end to the proximal end. The first hole 211 is in sealing contact with the valve stem 3 to ensure the sealing and guide the valve stem 3 at the same time. The second hole 212 is in clearance fit with the valve stem 3 to reduce the friction of the valve stem 3. The third hole 213 is slidably connected to the connecting block 31.

[0033] Please refer to Figure 2 Furthermore, the clamping assembly 32 also includes a thrust washer 321 disposed between the connecting block 31 and the third hole 213. The surface of the thrust washer 321 after matching grinding can achieve self-tight sealing and guide the valve stem 3 at the same time.

[0034] Please refer to Figure 2 Furthermore, the clamping assembly 32 also includes a first sleeve 322 sleeved on the side of the connecting block 31, and the first sleeve 322 is arranged in the gap between the extension portion 311 and the third hole 213, and is used to guide the pressure on the valve stem 3 to become a vertical force.

[0035] Please refer to Figure 3 , further, a sealing sleeve assembly 22 is also arranged between the first hole 211 and the valve stem 3, and the sealing sleeve assembly 22 includes a second shaft sleeve 221, a packing 222, a packing gland 223, and a packing gland 224 which are arranged in the first hole 211 from the proximal end to the distal end, and the packing gland 224 is connected to the distal end of the valve cover 2 through a second fixing member 225. Preferably, the second fixing member 225 includes a full-thread stud, a locking nut, a disc spring limiting sleeve, and a disc spring, and the disc spring is arranged in the disc spring limiting sleeve, and the full-thread stud passes through the disc spring limiting sleeve and the disc spring and is threadedly connected to the valve cover 2, and the locking nut is threadedly connected to the full-thread stud to compress the disc spring limiting sleeve.

[0036] Please refer to Figure 1 Furthermore, an inlet 11 and an outlet 12 are respectively provided on both sides of the valve body 1, and the flow control unit 4 includes a floating ball 43, a front valve seat 41 arranged at the front end of the floating ball 43, and a rear valve seat 42 arranged at the rear end of the floating ball 43. A second disc spring (not marked in the figure) is arranged at the front end of the front valve seat 41, and the rear valve seat 42 is fixed to the valve body 1 through an adjustment ring (not marked in the figure). Since the floating ball 43 floats relative to the valve stem 3, the second disc spring is used to support the inner annular surface of the front valve seat 41 to be in sealing contact with the outer surface of the floating ball 43, and the outer surface of the floating ball 43 to be in sealing contact with the inner annular surface of the rear valve seat 42. The through holes in the inlet 11, the front valve seat 41, the floating ball 43, the rear valve seat 42, and the outlet 12 are connected to form a flow channel.

[0037] Please refer to Figure 1Furthermore, the far end of the valve stem 3 is connected to an actuator 5 for driving the valve stem 3 to rotate between an open position and a closed position.

[0038] Please refer to Figure 1 Further, the valve cover 2 is connected to the far end of the valve body 1 through a third fixing member 23. Preferably, the third fixing member 23 includes a full-thread stud, a hexagonal nut, a locking washer, and an internally threaded cylindrical pin. The full-thread stud passes through the locking washer and is threadedly connected to the valve cover 2. The hexagonal nut is threadedly connected to the full-thread stud to tighten the valve cover 2. The internally threaded cylindrical pin is used for positioning the valve body 1 and the valve cover 2.

[0039] The specific workflow of the present invention is as follows:

[0040] The operator operates the actuator 5 to drive the valve stem 3 to rotate the floating ball 43, so that the flow channel in the valve body 1 is connected, and the medium flows out through the through holes in the inlet 11, the front valve seat 41, the floating ball 43, the rear valve seat 42, and the outlet 12. When the medium pressure is high, the medium provides an upward pressure to the connection block 31 that is sufficient to make the sealing surface between the thrust washers 321 and the sealing surface between the thrust washers 321 and the valve cover 2 reach the set sealing pressure ratio; when the medium pressure is low, the first disc spring 323 provides an upward pressure to the connection block 31 so that the sealing surface between the thrust washers 321 and the sealing surface between the thrust washers 321 and the valve cover 2 reach the set sealing pressure ratio.

[0041] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0042] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A reverse seal guide pre-tightening device for a floating ball valve, Features: The invention comprises a valve body (1) and a valve cover (2) connected to the distal end of the valve body (1), wherein a valve cavity (13) is provided in the valve body (1), wherein a flow control unit (4) is accommodated in the valve cavity (13), wherein a valve stem (3) passes through the valve cover (2), wherein the distal end of the valve stem (3) is connected to a floating ball (43) in the flow control unit (4) via a connecting block (31), wherein the diameter of the connecting block (31) is larger than the diameter of the valve stem (3), wherein a clamping assembly (32) is arranged at the distal end of the valve cover (2), wherein the clamping assembly (32) comprises a first disc spring (323) and a pressing ring (324), wherein the pressing ring (324) is fixed at the proximal end of the valve cover (2), and wherein the pressing ring (324) extends out of the valve cover (2) toward a portion of the connecting block (31), wherein one end of the first disc spring (323) abuts against the distal end of the portion of the pressing ring (324) extending out of the valve cover (2), and the other end abuts against the proximal end of the connecting block (31).

2. A reverse seal guide pre-tightening device for a floating ball valve as claimed in claim 1, Features: Extension parts (311) are arranged on both sides of the connection block (31), and the other end of the first disc spring (323) abuts against the extension part (311).

3. A reverse seal guide pre-tightening device for a floating ball valve as claimed in claim 2, Features: The pressing ring (324) is connected to the proximal end of the valve cover (2) via a first fixing member (325).

4. A reverse seal guide pre-tightening device for a floating ball valve as claimed in claim 2, Features: A step hole (21) is provided on the inner side of the valve cover (2), and the step hole (21) includes a first hole (211), a second hole (212), and a third hole (213) from the far end to the near end, the first hole (211) is in sealing contact with the valve stem (3), the second hole (212) is in clearance fit with the valve stem (3), and the third hole (213) is slidably connected to the connecting block (31).

5. A reverse seal guide pre-tightening device for a floating ball valve as claimed in claim 4, Features: The pressing assembly (32) further comprises a thrust washer (321) arranged between the connecting block (31) and the third hole (213).

6. A reverse seal guide pre-tightening device for a floating ball valve as claimed in claim 5, Features: The clamping assembly (32) further comprises a first shaft sleeve (322) sleeved on the side of the connecting block (31), wherein the first shaft sleeve (322) is arranged in the gap between the extension portion (311) and the third hole (213).

7. A reverse seal guide pre-tightening device for a floating ball valve as claimed in claim 4, Features: A sealing sleeve assembly (22) is also arranged between the first hole (211) and the valve stem (3), and the sealing sleeve assembly (22) comprises a second shaft sleeve (221), a packing (222), a packing gland (223), and a packing gland (224) which are arranged in sequence from the proximal end to the distal end in the first hole (211), and the packing gland (224) is connected to the distal end of the valve cover (2) via a second fixing member (225).

8. A reverse seal guide pre-tightening device for a floating ball valve as claimed in claim 1, Features: An inlet (11) and an outlet (12) are respectively provided on both sides of the valve body (1); the flow control unit (4) comprises a floating ball (43), a front valve seat (41) arranged at the front end of the floating ball (43), and a rear valve seat (42) arranged at the rear end of the floating ball (43); a second disc spring is arranged at the front end of the front valve seat (41); the rear valve seat (42) is fixed to the valve body (1) by an adjustment ring; the second disc spring is used to support the inner annular surface of the front valve seat (41) to be in sealing contact with the outer surface of the floating ball (43), and the outer surface of the floating ball (43) to be in sealing contact with the inner annular surface of the rear valve seat (42); the through holes in the inlet (11), the front valve seat (41), the floating ball (43), the rear valve seat (42), and the outlet (12) are connected together to form a flow channel.

9. A reverse seal guide pre-tightening device for a floating ball valve as claimed in claim 1, Features: The far end of the valve stem (3) is connected to an actuator (5).

10. The inverted seal guide pre-tightening device for a floating ball valve according to claim 1, Features: The valve cover (2) is connected to the far end of the valve body (1) via a third fixing member (23).

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