Opening device and opening method for field maintenance of low-temperature top-mounted ball valve

Abstract

The opening device comprises a ball valve mechanism and a dismounting mechanism, the ball valve mechanism comprises a valve body, valve seats and a ball seal, the valve seats are arranged on the left side and the right side in the valve body, and the ball seal is arranged on the top of the valve body and used for sealing the valve body; the dismounting mechanism comprises a positioning piece and two guide assemblies, the positioning piece is of an annular structure, a receding hole is formed in the center of the positioning piece, and the diameter of the receding hole is larger than that of the ball seal; the guide assembly is connected with the positioning piece, and the tail end of the guide assembly is obliquely arranged towards the central axis of the positioning piece; the guide assembly is in plug-in fit with the valve body for mounting or dismounting the ball seal; two sets of guide assemblies are arranged below a positioning piece of the dismounting mechanism, each set of guide assembly comprises two guide pieces arranged at intervals, the guide pieces are obliquely arranged towards the central axis of the positioning piece, and the valve seat is separated through the pressure generated when the guide pieces are inserted into the valve body so that the ball seal can be rapidly taken down from the valve body or rapidly installed.

Description

Technical Field

[0001] The invention belongs to the technical field of low-temperature top-mounted ball valves, and in particular relates to an opening device and an opening method for on-site maintenance of a low-temperature top-mounted ball valve. Background Art

[0002] The cryogenic top-mounted ball valve is a special ball valve for the liquid nitrogen and liquefied natural gas industries. The cryogenic top-mounted ball seal usually includes a valve body, a valve seat, a ball seal and a valve cover. The ball seal is arranged under the valve cover, and the valve cover and the valve body are fixedly connected by bolts. When the valve body is maintained, the valve cover and the ball seal need to be removed to maintain and service the inside of the valve body. The existing valve body usually uses an external wedge-shaped workpiece to insert into the valve seat, pry the ball seal and the valve seat, and separate the valve seat from the ball seal, thereby realizing the disassembly and installation process of the ball seal. There are many operating steps when disassembling the ball seal using this method. During the operation, it is necessary to open a hole in the valve body. After the maintenance is completed, a seal needs to be designed, which increases the risk of valve leakage. Moreover, when the valve body is maintained using the above method, the construction requirements are high and experienced operators are required to operate, thereby increasing the maintenance cost of the valve body. Summary of the invention

[0003] The purpose of the present invention is to provide an opening device and an opening method for on-site maintenance of a low-temperature top-mounted ball valve. Two groups of guide assemblies are arranged below the positioning member of the disassembly mechanism, and each group of guide assemblies includes two guide members arranged at intervals. The guide members are inclined toward the central axis position of the positioning member. The pressure of the guide members inserted into the valve body is used to separate the valve seat so that the ball seal can be quickly removed from the valve body or the ball seal can be quickly installed.

[0004] The present invention is achieved through the following technical solutions: An opening device for on-site maintenance of a low-temperature top-mounted ball valve comprises a ball valve mechanism and a disassembly mechanism, wherein the ball valve mechanism comprises a valve body, a valve seat and a ball seal, wherein the valve seat is arranged on the left and right sides of the inside of the valve body, and the ball seal is arranged on the top of the valve body for sealing the valve body; the disassembly mechanism comprises a positioning piece and two sets of guide assemblies, wherein the positioning piece is an annular structure, and a clearance hole is arranged at the center position of the positioning piece, and the diameter of the clearance hole is larger than the diameter of the ball seal; the guide assembly is connected to the positioning piece, and the end of the guide assembly is inclined toward the position of the central axis of the positioning piece; the guide assembly is plug-in-matched with the valve body for installing or disassembling the ball seal.

[0005] Furthermore, the positioning member is provided with a plurality of threaded holes, and the threaded holes are arranged at the edge of the positioning member; the valve body is provided with fixing bolts and nuts; the positioning member cooperates with the fixing bolts to adjust the insertion depth of the guide assembly in the valve body by rotating the nut.

[0006] Furthermore, each group of the guide assemblies includes two guide members, each of which is a rod-shaped structure. The positioning member is provided with a mounting hole, which is a rectangular structure and is inclined toward the central axis of the positioning member; the top end of the guide member is plug-fittedly connected to the mounting hole.

[0007] Furthermore, a positioning hole is provided on the side of the positioning member at the position of the mounting hole, and a plug hole is provided at the top position of the guide member. After the guide member is inserted into the mounting hole, a positioning screw is passed through the positioning hole and the plug hole to fix the guide member on the positioning member.

[0008] Furthermore, an inserting portion is provided at the end of the guide member, and the inserting portion is configured as a wedge-shaped structure.

[0009] Furthermore, at least one ball is arranged on the side of the guide member close to the valve seat, the ball is limited by the guide member, and the end of the ball is protruding from the side of the guide member.

[0010] Furthermore, both left and right sides of the valve seat are provided with limiting grooves, and the limiting grooves are used to limit the guide assembly.

[0011] A method for opening a cryogenic top-mounted ball valve for on-site maintenance, wherein the cryogenic top-mounted ball valve is opened on-site by using the above-mentioned disassembly mechanism, comprising the following steps: S1: Remove the valve cover and clean the ball seal surface; S2: Install the disassembly mechanism, insert the fixing bolt into the threaded hole of the positioning piece, and tighten the nut; S3: Turn the four nuts in sequence to make the guide enter the valve body and drive the valve seat to move; S4: Remove the ball seal, clean and maintain the inside of the valve body, install the ball seal, and remove the disassembly mechanism.

[0012] Furthermore, in step S2, when the disassembly mechanism is installed, the insertion portions of the four guide members are inserted between the valve seat and the ball seal and are located at the position of the limit groove of the ball seal.

[0013] Furthermore, in step S3, the specific operation method of rotating the four nuts in sequence is: rotating the four nuts clockwise or counterclockwise in sequence, rotating each nut the same number of turns, and rotating the four nuts into place in multiple times, so that the positioning member and the guide member gradually move downward to prevent the positioning member from deforming.

[0014] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1) In the present invention, two sets of guide assemblies are arranged below the positioning member of the disassembly mechanism, and each set of guide assemblies includes two guide members arranged at intervals, and the guide members are inclined toward the central axis position of the positioning member. The pressure of the guide members inserted into the valve body is used to separate the valve seat so that the ball seal can be quickly removed from the valve body or the ball seal can be quickly installed.

[0015] 2) In the present invention, two limit grooves are arranged on the valve seats on both sides of the valve body, and the limit grooves are used to limit the guide member so that the guide member slides along the limit grooves and is inserted into the valve body; in addition, two spaced balls are arranged on the side of the guide member close to the valve seat, thereby reducing the friction of the guide member on the valve seat and preventing the valve seat from being scratched to affect the air tightness of the valve body. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 It is a schematic diagram of the assembly structure of the disassembly mechanism and the valve body in the present invention.

[0018] Figure 2 It is a front view of the disassembly mechanism in the present invention.

[0019] Figure 3 It is a top view of the disassembly mechanism in the present invention.

[0020] Figure 4 It is a structural schematic diagram of the valve seat in the present invention.

[0021] Figure 5 It is a schematic diagram of the overall structure of the low-temperature top-mounted ball valve in the present invention.

[0022] Among them: 1-positioning piece, 11-threaded hole, 12-positioning screw, 13-allowance hole, 2-guide piece, 21-ball, 22-insertion part, 3-valve body, 4-valve seat, 41-limiting groove, 5-ball seal, 6-fixing bolt, 7-nut, 8-valve cover. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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.

[0024] Embodiment 1: The main structure of this embodiment is an opening device for on-site maintenance of a low-temperature top-mounted ball valve, such as Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, it includes a ball valve mechanism and a disassembly mechanism. The ball valve mechanism includes a valve body 3, a valve seat 4, a ball seal 5 and a valve cover 8 on the top. The valve seat 4 is arranged on the left and right sides of the valve body 3, the ball seal 5 is arranged on the top of the valve body 3 to seal the valve body 3, and the valve cover 8 is arranged on the top of the ball seal 5 to further seal the valve body 3. The valve body 3 is provided with fixing bolts 6 and nuts 7. The valve cover 8 is fixed to the valve body 3 by fixing bolts 6 and nuts 7. To disassemble the valve cover 8, it is only necessary to unscrew the nuts 7. However, to disassemble the ball seal 5, it is necessary to first separate the valve seats 4 on both sides of the ball seal 5 before the ball seal 5 can be removed; the disassembly mechanism is used to disassemble the ball seal 5. The disassembly mechanism includes a positioning member 1 and two sets of guide components. The positioning member 1 is annular in structure. A clearance hole 13 is arranged at the center of the positioning member 1. The diameter of the clearance hole 13 is larger than the diameter of the ball seal 5. When disassembling the ball seal 5, the ball seal 5 can be taken out from the clearance hole 13 of the positioning member 1, or it can be taken out by a rope or a binding. The end of the ball seal 5 is tightened with a belt, and as the positioning piece 1 is pressed down, the valve seat 4 is separated and then the ball seal 5 is lifted; the guide assembly is connected to the positioning piece 1, and the end of the guide assembly is inclined toward the central axis position of the positioning piece 1. When the guide assembly is inserted into the valve body 3, as the insertion depth increases, the valve seat 4 can expand and the ball seal 5 can be squeezed upward, so that the ball seal 5 can be quickly removed; the guide assembly is plug-in-fitted and connected to the valve body 3, and a plurality of threaded holes 11 are provided on the positioning piece 1 on the outside of the guide assembly. The threaded holes 11 are provided at the edge of the positioning piece 1, and the threaded holes 11 can cooperate with the four fixing bolts 6 that fix the valve cover 8; after the valve cover 8 is removed, the positioning piece 1 is plug-in-fitted with the fixing bolts 6 of the valve body 3, and the nuts 7 are pressed above the positioning piece 1. The positioning piece 1 is gradually moved downward by gradually rotating the four nuts 7 respectively, so that the guide assembly is gradually inserted into the valve body 3 to expand the valve seat 4, thereby removing the ball seal 5.

[0025] Embodiment 2: Based on the above embodiment, this embodiment further defines the guide assembly and the valve body 3, such as Figure 1 , Figure 2 and Figure 4As shown, each guide assembly includes two guide members 2, which are arranged at intervals, and the four guide members 2 are arranged in an array on the positioning member 1. The guide members 2 are all inclined toward the central axis of the positioning member 1, and the angle between the guide member 2 and the surface of the positioning member 1 is 60°-75°; the guide member 2 is a rod-shaped structure, and a mounting hole is provided on the positioning member 1. The mounting hole is a rectangular structure and is inclined toward the central axis of the positioning member 1, and the top of the guide member 2 is plug-fitted and connected with the mounting hole; at the same time, a positioning hole is provided on the side of the positioning member 1 at the position of the mounting hole, and the positioning hole is connected with the mounting hole, and a plug hole is provided at the top position of the guide member 2. After the guide member 2 is inserted into the mounting hole, the positioning screw 12 is passed through the positioning hole and the plug hole to fix the guide member 2 on the positioning member 1, so as to further prevent the guide member 2 from rotating; an insertion portion 2 is provided at the end of the guide member 2 2, the inserting part 22 is set as a wedge-shaped structure, and the inserting part 22 can be inserted into the gap between the ball seal 5 and the valve seat 4; two balls 21 are arranged on the side of the guide member 2 close to the valve seat 4, and the two balls 21 are arranged at intervals up and down. The balls 21 are limited by the guide member 2, and the balls 21 can rotate in the guide member 2. The ends of the balls 21 are protruding from the side of the guide member 2; the left and right sides of the valve seat 4 are provided with limiting grooves 41, and the limiting grooves 41 are used to limit the guide assembly. After the guide member 2 is inserted into the valve body 3, the balls 21 on the guide member 2 abut against the limiting grooves 41 of the valve seat 4, thereby avoiding large friction between the guide member 2 and the valve seat 4 to damage the valve seat 4; when installing the ball seal 5, the disassembly mechanism is inserted into the valve body 3 to expand the gap between the valve seats 4, and the ball seal 5 is pressed tightly. After pressing the ball seal 5, the disassembly mechanism can be pulled out, and the operation is simple and quick. The other parts of this embodiment are the same as the above embodiment, and will not be repeated here.

[0026] Embodiment 3: A method for opening a cryogenic top-mounted ball valve for on-site maintenance, wherein the cryogenic top-mounted ball valve is opened on-site by using the above-mentioned disassembly mechanism, comprising the following steps: S1: Remove the valve cover 8 and clean the surface of the ball seal 5; S2: Install the disassembly mechanism, insert the fixing bolt 6 into the threaded hole 11 of the positioning member 1, and tighten the nut 7; S3: Turn the four nuts 7 in sequence to make the guide member 2 enter the valve body 3 and drive the valve seat 4 to move; S4: Remove the ball seal 5, clean and maintain the inside of the valve body 3, install the ball seal 5, and remove the disassembly mechanism.

[0027] When the cryogenic top-mounted ball valve is opened for on-site maintenance, first remove the valve cover 8, clean and inspect the surface of the ball seal 5, then install the disassembly mechanism, align the threaded holes 11 on the positioning member 1 with the four fixing bolts 6 respectively, check whether the angle of the guide member 2 is correct, so that the insertion portions 22 of the four guide members 2 are all inserted between the valve seat 4 and the ball seal 5 and are located at the position of the limit groove 41 of the ball seal 5, screw in the nut 7, then turn the four nuts 7 clockwise or counterclockwise in sequence, each nut 7 is turned the same number of times each time, and the four nuts 7 are turned into place in sequence in multiple times, so that the positioning member 1 and the guide member 2 are gradually moved down, and the nuts 7 are gradually turned in sequence to prevent the positioning member 1 from deforming; after the valve seat 4 is displaced, the ball seal 5 is loosened and the ball seal 5 can be taken out for maintenance and cleaning of the inside of the valve body 3. During maintenance and cleaning, the disassembly mechanism can be left unremoved. After the maintenance and cleaning is completed, the ball seal 5 is installed in place, and after the ball seal 5 is pressed, the nut 7 is unscrewed, the disassembly mechanism is pulled out, and the valve cover 8 is installed. The cleaning and maintenance process of the entire cryogenic top-mounted ball valve is simple and efficient.

[0028] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. used to indicate the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship commonly placed when the product of the invention is used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0029] In addition, if the terms "horizontal" or "vertical" appear in the description of the present invention, it does not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. An opening device for on-site maintenance of a cryogenic top-mounted ball valve, characterized in that: It includes a ball valve mechanism and a disassembly mechanism, the ball valve mechanism includes a valve body, a valve seat and a ball seal, the valve seat is arranged on the left and right sides of the valve body, and the ball seal is arranged on the top of the valve body to seal the valve body; the disassembly mechanism includes a positioning piece and two sets of guide components, the positioning piece is annular in structure, a clearance hole is arranged at the center position of the positioning piece, and the diameter of the clearance hole is larger than the diameter of the ball seal; the guide component is connected to the positioning piece, and the end of the guide component is inclined toward the center axis position of the positioning piece; the guide component is plug-in-matched with the valve body for installing or disassembling the ball seal.

2. The opening device for on-site maintenance of a cryogenic top-mounted ball valve as claimed in claim 1, characterized in that: The positioning member is provided with a plurality of threaded holes, and the threaded holes are arranged at the edge of the positioning member; the valve body is provided with fixing bolts and nuts; the positioning member cooperates with the fixing bolts to adjust the insertion depth of the guide assembly in the valve body by rotating the nut.

3. The opening device for on-site maintenance of a cryogenic top-mounted ball valve as claimed in claim 1, characterized in that: Each group of the guide components includes two guide members, each of which is a rod-shaped structure. The positioning member is provided with a mounting hole, which is a rectangular structure and is inclined toward the central axis of the positioning member; the top end of the guide member is plug-fitted and connected to the mounting hole.

4. The opening device for on-site maintenance of a cryogenic top-mounted ball valve as claimed in claim 3, characterized in that: A positioning hole is arranged on the side of the positioning member at the position of the mounting hole, and a plug hole is arranged at the top position of the guide member. After the guide member is inserted into the mounting hole, a positioning screw is passed through the positioning hole and the plug hole to fix the guide member on the positioning member.

5. The opening device for on-site maintenance of a cryogenic top-mounted ball valve as claimed in claim 3, characterized in that: An inserting portion is arranged at the end of the guide member, and the inserting portion is arranged as a wedge-shaped structure.

6. The opening device for on-site maintenance of a cryogenic top-mounted ball valve as claimed in claim 3, characterized in that: At least one ball is arranged on the side of the guide member close to the valve seat, the ball is limited by the guide member, and the end of the ball is protruding from the side of the guide member.

7. The opening device for on-site maintenance of a cryogenic top-mounted ball valve as claimed in claim 1, characterized in that: Limiting grooves are arranged on both the left and right sides of the valve seat, and the limiting grooves are used to limit the guide assembly.

8. A method for opening a cryogenic top-mounted ball valve for on-site maintenance, characterized in that: The method of opening the cryogenic top-mounted ball valve on site by using the disassembly mechanism as described in any one of claims 1 to 7 comprises the following steps: S1: Remove the valve cover and clean the ball seal surface; S2: Install the disassembly mechanism, insert the fixing bolt into the threaded hole of the positioning piece, and tighten the nut; S3: Turn the four nuts in sequence to make the guide enter the valve body and drive the valve seat to move; S4: Remove the ball seal, clean and maintain the inside of the valve body, install the ball seal, and remove the disassembly mechanism.

9. The method for opening a cryogenic top-mounted ball valve for on-site maintenance as claimed in claim 8, characterized in that: In step S2, when the disassembly mechanism is installed, the insertion portions of the four guide members are inserted between the valve seat and the ball seal and are located at the position of the limit groove of the ball seal.

10. The method for opening a cryogenic top-mounted ball valve for on-site maintenance as claimed in claim 8, characterized in that: In step S3, the specific operation method of rotating the four nuts in sequence is: rotating the four nuts clockwise or counterclockwise in sequence, rotating each nut the same number of turns, rotating the four nuts into place in multiple times, so that the positioning member and the guide member gradually move downward to prevent the positioning member from deforming.

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