Large-diameter track ball valve seat cold assembly and its using method

Abstract

This invention belongs to the field of hydraulic valves, specifically relating to a cold-fitting assembly for a large-diameter ball valve seat and its usage method. The large-diameter ball valve includes a valve body and a valve seat. The valve body has a mounting groove for installing the valve seat. The outer circumferential surface of the valve seat has an assembly ramp inclined towards the axis, and the inner circumferential surface of the valve seat has an annular process groove. The cold-fitting assembly includes: a cryogenic connection module for connecting to the valve seat; and a lifting assembly for transporting and installing the valve seat. This cold-fitting assembly can cooperate with the valve seat to achieve reliable valve seat assembly and provide effective protection for the operator.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic valves, specifically relating to a cold-fitting assembly for a large-diameter orbital ball valve seat and its usage method. Background Technology

[0002] During the cold assembly of large-diameter ball valve seats, the seats must first be immersed in liquid nitrogen at -196℃. Afterward, the seats are removed from the liquid nitrogen tank and placed into the valve body annulus. This placement process must be completed within a short time; exceeding this time will cause the seats to warm up, become too large, and become impossible to assemble or jam. However, due to the large outer diameter and weight of the seats, and the fact that the diameter of the valve body cavity is less than 50mm on one side, the operating space for the seats in the cavity is limited. If the seats cannot be effectively and smoothly delivered to the intended position and sufficient assembly clearance cannot be ensured, the seats cannot be installed correctly, easily causing damage to both the seats and the valve body.

[0003] If the valve body or seat is damaged during assembly, it must be repaired and qualified before reassembly. Both the valve body and seat are precision parts, and repairs after damage are time-consuming and expensive. Furthermore, the valve seat is immersed in liquid nitrogen at -196°C, and its subsequent removal and assembly are all at extremely low temperatures. Improper handling and inadequate protection could potentially cause serious injury to the operator.

[0004] Currently, in the cold assembly process of large-diameter ball valve seats, existing technology makes the assembly component into an integral rigid frame connected to the valve seat. However, when experiencing a drastic temperature change of over 200°C, such as "room temperature assembly → immersion in -196°C liquid nitrogen → removal from liquid nitrogen", significant thermal stress will be generated between the integral assembly component and the valve seat due to the difference in the thermal expansion coefficient of the materials and structural constraints. This may lead to loosening of the connection, jamming, or even local plastic deformation of the integral assembly component or valve seat. Summary of the Invention

[0005] To address the problems existing in the prior art, the purpose of this invention is to provide a cold-fitting assembly for a large-diameter ball valve seat and its usage method. This cold-fitting assembly can cooperate with the valve seat to achieve reliable assembly of the valve seat and provide effective protection for the operator.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: A cold-fitting assembly for a large-diameter orbital ball valve seat, the large-diameter orbital ball valve including a valve body and a valve seat, the valve body having a mounting groove for mounting the valve seat, the outer circumferential surface of the valve seat having an axially inclined mounting surface, and the inner circumferential surface of the valve seat having an annular process groove, the cold-fitting assembly comprising: A refrigeration connection module, the refrigeration connection module being used to connect to the valve seat; A lifting assembly for transporting and installing the valve seat; The freezing connection module includes a first connection plate, a second connection plate, a third connection plate, and a fourth connection plate that are sequentially assembled; one side of the first connection plate and the third connection plate is provided with a boss that mates with the process tank; The hoisting assembly includes a movable base, a first crossbeam is provided above the base, the first crossbeam is connected to the base via a first longitudinal beam, a lifting assembly is provided on the first longitudinal beam, the lifting assembly is used to drive the first crossbeam to rise and fall along the longitudinal direction; wherein, the first crossbeam is connected to the refrigeration connection module.

[0007] Preferably, the freezing connection module further includes a lifting plate, which is connected to four connecting plates by quick-release screws, and two first lifting rings are provided on one side of the lifting plate, which are symmetrical about the center of the lifting plate.

[0008] Preferably, each of the four connecting discs has a notch at its end, and the four notches combine to form a weight-reducing hole. The central angle θ of the first connecting disc and the third connecting disc is 90°~140°.

[0009] Preferably, two second lifting rings are arranged sequentially along the length of the first crossbeam, and a flexible steel cable is provided between the first lifting ring and the second lifting ring.

[0010] Preferably, a pushing assembly is provided on the first crossbeam, the pushing assembly is located between the two second lifting rings, and the two second lifting rings are symmetrically arranged about the pushing assembly.

[0011] Preferably, it also includes a support head, one side of which is connected to the working end of the pushing assembly, and the other side is connected to the lifting plate of the refrigeration connection module, so as to uniformly transmit the thrust of the pushing assembly to the valve seat.

[0012] Preferably, a second crossbeam is provided above the first crossbeam, and the first crossbeam and the second crossbeam are connected by a second longitudinal beam. A support rod is also provided between the first crossbeam and the second crossbeam. When the working end of the pushing assembly pushes the support head, the two ends of the support rod abut against the first crossbeam and the second crossbeam respectively, so as to reduce the deformation of the first crossbeam.

[0013] Preferably, a positioning rod is installed on the valve body, and a limiting block is provided on the positioning rod. The limiting block cooperates with the second longitudinal beam. When the second longitudinal beam abuts against the limiting block, the axis of the valve seat coincides with the axis of the mounting groove.

[0014] A method for using a cold-fitting assembly of a large-diameter orbital ball valve seat includes the following steps: Step S1: Place the valve body on the assembly platform with the mounting groove facing upwards; Step S2: Insert the bosses of the first connecting plate and the third connecting plate into the process groove on the inner circumferential surface of the valve seat, adjust the position of the first connecting plate and the third connecting plate, and insert the second connecting plate and the fourth connecting plate between the first connecting plate and the third connecting plate; after the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate are assembled, place the lifting plate on the surface of the four connecting plates, and use the quick-release screws to connect and fix the lifting plate to the four connecting plates to form the freezing connection module; Step S3: Insert the flexible steel cable between the first lifting ring and the second lifting ring, then control the lifting assembly to drive the first crossbeam to rise and lift the valve seat, drive the lifting assembly to move as a whole, lift the valve seat to directly above the liquid nitrogen at -196℃, control the lifting assembly to drive the first crossbeam to descend, and lower the valve seat into the liquid nitrogen to immerse it until the size shrinkage is stable; Step S4: After the valve seat is frozen, remove the valve seat from the liquid nitrogen, then move the hoisting assembly to hoist the valve seat into the valve cavity of the valve body, and make the second longitudinal beam of the hoisting assembly abut against the limiting block. Under the guidance of the limiting block, the valve seat is hoisted to the predetermined assembly position. Step S5: Control the lifting assembly to slowly lower the valve seat to the annular position of the mounting groove, so that the mounting inclined surface on the valve seat contacts the mounting groove, and then remove the flexible steel cable; Step S6: Place the support head at the center of the lifting plate, then control the push assembly to move so that the working end of the push assembly abuts against the support head and continuously outputs thrust, and finally assemble the valve seat into the predetermined position in the mounting groove; Step S7: After the temperature of the valve seat returns to room temperature, remove the lifting plate and the four connecting plates in sequence.

[0015] Preferably, step S6 further includes the following steps: Step S61: Control the working end of the pushing assembly to abut against the support head; Step S62: Insert the support rod between the first crossbeam and the second crossbeam; Step S63: Control the pushing assembly to continuously output thrust until the valve seat is assembled to the predetermined position.

[0016] Compared with the prior art, the cold-fitting assembly of a large-diameter orbital ball valve seat and its usage method provided by the present invention have the following beneficial technical effects: 1. Compared to external clamping and internal expansion clamping methods, the valve seat in this invention has a process groove. The freezing connection module cooperates with the process groove, which can reduce the plastic deformation of the valve seat caused by clamping. The split freezing connection module is connected to the valve seat at room temperature. After that, the operator can operate remotely using the hoisting component without touching the valve seat or freezing connection module again, achieving a one-time room temperature connection and low temperature isolation throughout the process, reducing the risk of frostbite. The four connecting plates and hoisting plates used are all independent and replaceable parts, which facilitates separate installation. In addition, if one of them is damaged, it can be replaced individually without replacing the entire freezing connection module.

[0017] 2. The present invention provides several cooling channels to guide liquid nitrogen into and fully wet the inner surface of the valve seat, so that the valve seat shrinks fully and stably, providing reliable dimensional assurance for smooth assembly in a short time. The notches at the ends of the four connecting plates provide flow channels for liquid nitrogen to enter the cooling channels, and also reduce the weight of the device.

[0018] 3. This invention integrates lifting rings and a pushing assembly on the first crossbeam of the lifting assembly, enabling simultaneous handling of valve seat transport and assembly. The two lifting rings are symmetrically arranged about the pushing assembly to ensure the valve seat is stably placed at the annular opening of the mounting groove and to evenly transmit the pushing force of the pushing assembly to the valve seat. The first crossbeam and base, as well as the first and second crossbeams, all adopt a C-shaped structure to ensure the valve seat can be smoothly inserted from the valve body cavity without interference.

[0019] A support rod is provided between the first crossbeam and the second crossbeam. When the working end of the pushing assembly pushes the support head, both ends of the support rod abut against the first crossbeam and the second crossbeam respectively, so as to reduce the deformation of the first crossbeam and ensure that the pushing assembly pushes the valve seat to the designated position.

[0020] 4. The method of using the cold assembly assembly of the large-diameter orbital ball valve seat provided by the present invention will significantly reduce the assembly difficulty of the valve seat and effectively reduce the risk of damage to the internal parts of the valve. It performs particularly well in the assembly of orbital ball valves with a diameter of 20 inches or more and has extremely high applicability. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the cold-packing assembly of the present invention; Figure 2 This is a schematic diagram of the structure of the cryogenic connection module of the present invention; Figure 3 This is a partially enlarged schematic diagram of the valve seat of the present invention; Figure 4 This is a top view of the cryogenic connection module of the present invention; Figure 5 This is a schematic diagram of another embodiment of the connecting disk of the present invention; Figure 6 This is a schematic diagram of the structure of the valve seat during hoisting according to the present invention; Figure 7 This is a schematic diagram of the valve seat assembly intermediate state of the present invention; Figure 8 This is a schematic diagram of the valve seat of the present invention in place.

[0022] The meanings of the reference numerals in the figures are as follows: 1. Valve body; 2. Valve seat; 3. Refrigeration connection module; 4. Lifting assembly; 11. Mounting groove; 21. Assembly ramp; 22. Process groove; 31. First connecting plate; 32. Second connecting plate; 33. Third connecting plate; 34. Fourth connecting plate; 35. Lifting plate; 36. Quick-release screw; 37. First lifting ring; 38. Boss; 39. Weight reduction hole; 391. Cooling channel; 41. Base; 42. First crossbeam; 43. Second crossbeam; 44. Positioning rod; 45. Lifting assembly; 46. Limiting block; 47. Pushing assembly; 48. Flexible rope; 49. Support head; 50. Support rod; 421. Second lifting ring. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0024] Therefore, the following detailed description of embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely illustrates some embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0025] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the present invention can be combined with each other.

[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. These terms are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0028] See appendix Figure 1 -Appendix Figure 8 As shown, the present invention provides a cold-fitting assembly for a large-diameter orbital ball valve seat. The large-diameter orbital ball valve includes a valve body 1 and a valve seat 2. The valve body 1 is provided with a mounting groove 11 for mounting the valve seat 2, and the outer peripheral surface of the valve seat 2 is provided with an assembly inclined surface 21 that is inclined toward the axis.

[0029] The refrigerated assembly includes a refrigeration connection module 3, which is used to connect to the valve seat 2; and a hoisting assembly 4, which is connected to the refrigeration connection module 3 for transporting and installing the valve seat 2.

[0030] In practice, the inventors discovered that existing technologies often employ external clamping (similar to a chuck) or internal expansion clamping for valve seats. However, both external clamping and internal expansion methods cause deformation of the valve seat, which hinders accurate subsequent installation. Furthermore, in the process scenario of this invention, the cryogenic connection module 3 and the valve seat undergo a -196°C liquid nitrogen freezing process. Due to the different coefficients of thermal expansion between the cryogenic connection module 3 and the valve seat, their deformation during the freezing process differs, leading to either excessive clamping force (damaging the valve seat) or insufficient clamping force (ineffective valve seat clamping). To minimize plastic deformation of the valve seat due to clamping and reduce the risk of loosening or jamming between the cryogenic connection module 3 and the valve seat caused by temperature differences exceeding 200°C, this invention proposes the following technical solution: An annular process groove 22 is provided on the inner circumferential surface of the valve seat 2. The refrigeration connection module 3 includes a first connecting plate 31, a second connecting plate 32, a third connecting plate 33, and a fourth connecting plate 34, which are sequentially assembled. A boss 38 that mates with the process groove 22 is provided on one side of the first connecting plate 31 and the third connecting plate 33. By creating the process groove 22 on the valve seat 2 and having it mate with the boss 38, deformation of the valve seat caused by external clamping or internal expansion clamping methods is avoided. It should be noted that the process groove should not be located on the sealing surface at the bottom of the valve seat 2, so as not to adversely affect the sealing performance.

[0031] Preferably, the freezing connection module 3 is fitted with the inner side of the valve seat 2 with a clearance, and the second connection plate 32 and the fourth connection plate 34 are in circumferential contact with the first connection plate 31 and the third connection plate 33 respectively, so as to prevent the first connection plate 31 and the third connection plate 33 from rotating.

[0032] The hoisting assembly 4 includes a movable base 41, with a first crossbeam 42 positioned above the base 41. The first crossbeam 42 is connected to the base 41 via a first longitudinal beam. A lifting assembly 45 is mounted on the first longitudinal beam, which is used to move the first crossbeam 42 up and down in the longitudinal direction. The refrigeration connection module 3 is connected to the first crossbeam 42.

[0033] Preferably, the freezing connection module 3 further includes a lifting plate 35, which is connected to four connecting plates by quick-release screws 36. Two first lifting rings 37 are provided on one side of the lifting plate 35, which are symmetrical about the center of the lifting plate 35.

[0034] The above setup has the following advantages: (1) Compared with the external clamping and internal expansion clamping methods, the valve seat in this invention has a process groove. The freezing connection module cooperates with the process groove, which can reduce the plastic deformation of the valve seat caused by clamping; (2) The split freezing connection module is connected to the valve seat at room temperature. After that, the operator can use the hoisting component to operate remotely without touching the valve seat or freezing connection module again, realizing a one-time room temperature connection and low temperature isolation throughout the process, reducing the risk of frostbite; (3) The four connecting plates and hoisting plates used are all independent replaceable parts, which are convenient for separate installation; in addition, if one of them is damaged, it can be replaced separately without replacing the entire freezing connection module.

[0035] Preferably, each of the four connecting discs has a notch at its end, and the four notches combine to form a weight-reducing hole 39. The central angle θ of the first connecting disc 31 and the third connecting disc 33 is 90°~140°. Several cooling channels 391 are provided radially along each connecting disc, and the two ends of the cooling channels 391 are respectively connected to the outer peripheral surface of the connecting disc and the notch.

[0036] The above setup has the following advantages: (1) Setting up several cooling channels can guide liquid nitrogen into and fully wet the inner surface of the valve seat, so that the valve seat shrinks fully and stably, providing reliable dimensional assurance for smooth assembly in a short time; (2) The notches at the ends of the four connecting plates provide a flow channel for liquid nitrogen to enter the cooling channel, and can also reduce the weight of the device.

[0037] Preferably, two second lifting rings 421 are sequentially arranged along the length of the first crossbeam 42, and a flexible rope 48 is provided between the first lifting ring 37 and the second lifting ring 421. A pushing assembly 47 is provided on the first crossbeam 42, located between the two second lifting rings 421, and the two second lifting rings 421 are symmetrically arranged about the pushing assembly 47. The working end of the pushing assembly 47 is connected to the refrigeration connection module 3 and is used to push the refrigeration connection module 3 to move vertically so as to install the valve seat 2 into the predetermined position in the mounting groove 11. In this embodiment, the pushing assembly 47 uses a hydraulic jack to push the refrigeration connection module 3 to move vertically, stably installing the valve seat 2 into the predetermined position in the mounting groove 11. Of course, it is not limited to the above arrangement, and other actuating components, such as electric push rods, can also be used to push the refrigeration connection module 3 to move.

[0038] Preferably, it also includes a support head 49, one side of which is connected to the working end of the pushing assembly 47, and the other side is connected to the lifting plate 35 of the freezing connection module 3, so as to evenly transmit the thrust of the pushing assembly 47 to the valve seat 2.

[0039] Preferably, a second crossbeam 43 is also provided on the upper part of the first crossbeam 42. The first crossbeam 42 and the second crossbeam 43 are connected by a second longitudinal beam. A support rod 50 is also provided between the first crossbeam 42 and the second crossbeam 43. When the working end of the pushing assembly 47 pushes the support head 49, the two ends of the support rod 50 abut against the first crossbeam 42 and the second crossbeam 43 respectively, so as to reduce the deformation of the first crossbeam 42.

[0040] This invention integrates lifting rings and a pushing assembly on the first crossbeam of the lifting assembly, simultaneously facilitating the transfer and assembly of the valve seat. The two lifting rings are symmetrically arranged about the pushing assembly, ensuring the valve seat is stably placed at the annular opening of the mounting groove and that the pushing force of the pushing assembly is evenly transmitted to the valve seat. The first crossbeam and base, as well as the first and second crossbeams, all adopt a C-shaped structure to ensure the valve seat can be smoothly inserted from the valve body cavity without interference.

[0041] A support rod is provided between the first crossbeam and the second crossbeam. When the working end of the pushing assembly pushes the support head, both ends of the support rod abut against the first crossbeam and the second crossbeam respectively, so as to reduce the deformation of the first crossbeam and ensure that the pushing assembly pushes the valve seat to the designated position.

[0042] Preferably, a positioning rod 44 is installed on the valve body 1, and a limiting block 46 is provided on the positioning rod 44. The limiting block 46 cooperates with the second longitudinal beam. When the second longitudinal beam abuts against the limiting block 46, the axis of the valve seat 2 coincides with the axis of the mounting groove 11.

[0043] The present invention also provides a method for using a cold-fitting assembly of a large-diameter orbital ball valve seat, the method comprising the following steps: Step S1: Place the valve body 1 on the assembly platform (not shown in the figure) with the mounting groove 11 facing upwards.

[0044] Step S2: Insert the bosses 38 of the first connecting plate 31 and the third connecting plate 33 into the annular process groove 22 on the inner circumferential surface of the valve seat 2, adjust the position of the first connecting plate 31 and the third connecting plate 33, and insert the second connecting plate 32 and the fourth connecting plate 34 between the first connecting plate 31 and the third connecting plate 33; after the first connecting plate 31, the second connecting plate 32, the third connecting plate 33 and the fourth connecting plate 34 are spliced, place the lifting plate 35 on the surface of the four connecting plates, and use quick-release screws 36 to connect and fix the lifting plate 35 to the four connecting plates to form the freezing connection module 3.

[0045] Step S3: Insert a flexible rope 48 between the first lifting ring 37 and the second lifting ring 421. Then, control the lifting assembly 45 to work, drive the first crossbeam 42 to rise, lift the valve seat 2, drive the lifting assembly 4 to move as a whole, and lift the valve seat 2 directly above the liquid nitrogen at -196℃. At this time, the pushing assembly 47 is in the retracted state. Control the lifting assembly 45 to work, drive the first crossbeam 42 to descend, and lower the valve seat 2 into the liquid nitrogen for immersion until the size shrinks and stabilizes.

[0046] Step S4: After the valve seat 2 has been frozen, remove the valve seat 2 from the liquid nitrogen, then move the hoisting assembly 4 to hoist the valve seat 2 into the valve cavity of the valve body 1, and make the second longitudinal beam of the hoisting assembly 4 abut against the limiting block 46. Under the guidance of the limiting block 46, the valve seat 2 is hoisted to the predetermined assembly position.

[0047] Step S5: Control the lifting assembly 45 to operate and slowly lower the valve seat 2 to the ring position of the mounting groove 11 so that the mounting inclined surface 21 on the valve seat 2 contacts the mounting groove 11, and then remove the flexible rope 48.

[0048] Step S6: Place the support head 49 at the center of the lifting plate 35, and then control the push assembly 47 to move so that the working end of the push assembly 47 abuts against the support head 49 and continuously outputs thrust, and finally assembles the valve seat 2 into the predetermined position in the mounting groove 11.

[0049] Preferably, step S6 is completed using the following steps: Step S61: Control the working end of the pushing assembly 47 to abut against the support head 49; Step S62: Insert the support rod 50 between the first crossbeam 42 and the second crossbeam 43; Step S63: Control the pushing assembly 47 to continuously output thrust, and evenly transmit the thrust of the pushing assembly 47 to the valve seat 2 until the valve seat 2 is assembled to the predetermined position.

[0050] Step S7: After the temperature of valve seat 2 returns to room temperature, remove the lifting plate 35 and the four connecting plates in sequence.

[0051] The method of using the cold assembly assembly of the large-diameter orbital ball valve seat provided by the present invention will significantly reduce the assembly difficulty of the valve seat and effectively reduce the risk of damage to the internal parts of the valve. It performs particularly well in the assembly of orbital ball valves with a diameter of 20 inches or more and has extremely high applicability.

[0052] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described herein. Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to the specific embodiments described above. Therefore, any modifications or equivalent substitutions to the present invention, as well as all technical solutions and improvements that do not depart from the spirit and scope of the invention, are covered within the scope of the claims of the present invention.

Claims

1. A cold-fitting assembly for a large-diameter orbital ball valve seat, the large-diameter orbital ball valve comprising a valve body and a valve seat, characterized in that, The valve body is provided with a mounting groove for mounting the valve seat, the outer circumferential surface of the valve seat is provided with an assembly inclined surface inclined towards the axis, and the inner circumferential surface of the valve seat is provided with an annular process groove. The cold-fit assembly includes: A refrigeration connection module, which is used to connect to the valve seat; A lifting assembly for transporting and installing the valve seat; The freezing connection module includes a first connection plate, a second connection plate, a third connection plate, and a fourth connection plate that are sequentially assembled; one side of the first connection plate and the third connection plate is provided with a boss that mates with the process tank; The hoisting assembly includes a movable base, a first crossbeam is provided above the base, the first crossbeam is connected to the base via a first longitudinal beam, a lifting assembly is provided on the first longitudinal beam, the lifting assembly is used to drive the first crossbeam to rise and fall along the longitudinal direction; wherein, the first crossbeam is connected to the refrigeration connection module.

2. The cold-packing component as described in claim 1, characterized in that: The refrigeration connection module also includes a lifting plate, which is connected to four connecting plates by quick-release screws. Two first lifting rings are provided on one side of the lifting plate, symmetrically arranged along the center of the lifting plate.

3. The cold-packing component as described in claim 2, characterized in that: The ends of the four connecting discs are provided with notches, and the four notches are combined to form a weight reduction hole. The central angle θ of the first connecting disc and the third connecting disc is 90°~140°.

4. The cold-packing component as described in claim 3, characterized in that: Two second lifting rings are sequentially arranged along the length of the first crossbeam, and a flexible steel cable is provided between the first lifting ring and the second lifting ring.

5. The cold-packing assembly as described in claim 4, characterized in that: A pushing assembly is provided on the first crossbeam. The pushing assembly is located between the two second lifting rings, and the two second lifting rings are symmetrically arranged about the pushing assembly.

6. The cold-packing assembly as described in claim 5, characterized in that: It also includes a support head, one side of which is connected to the working end of the pushing assembly, and the other side is connected to the lifting plate of the refrigeration connection module, so as to evenly transmit the thrust of the pushing assembly to the valve seat.

7. The cold-packing assembly as described in claim 6, characterized in that: A second crossbeam is also provided above the first crossbeam. The first crossbeam and the second crossbeam are connected by a second longitudinal beam. A support rod is also provided between the first crossbeam and the second crossbeam. When the working end of the pushing assembly pushes the support head, the two ends of the support rod abut against the first crossbeam and the second crossbeam respectively, so as to reduce the deformation of the first crossbeam.

8. The cold-packing assembly as described in claim 7, characterized in that: A positioning rod is installed on the valve body, and a limit block is provided on the positioning rod. The limit block cooperates with the second longitudinal beam. When the second longitudinal beam abuts against the limit block, the axis of the valve seat coincides with the axis of the mounting groove.

9. A method of using the cold-packing component as described in claim 8, characterized in that, Includes the following steps: Step S1: Place the valve body on the assembly platform with the mounting groove facing upwards; Step S2: Insert the bosses of the first connecting plate and the third connecting plate into the process groove on the inner circumferential surface of the valve seat, adjust the position of the first connecting plate and the third connecting plate, and insert the second connecting plate and the fourth connecting plate between the first connecting plate and the third connecting plate; after the first connecting plate, the second connecting plate, the third connecting plate and the fourth connecting plate are assembled, place the lifting plate on the surface of the four connecting plates, and use the quick-release screws to connect and fix the lifting plate to the four connecting plates to form the freezing connection module; Step S3: Insert the flexible steel cable between the first lifting ring and the second lifting ring, then control the lifting assembly to drive the first crossbeam to rise and lift the valve seat, drive the lifting assembly to move as a whole, lift the valve seat to directly above the liquid nitrogen at -196℃, control the lifting assembly to drive the first crossbeam to descend, and lower the valve seat into the liquid nitrogen to immerse it until the size shrinkage is stable; Step S4: After the valve seat is frozen, remove the valve seat from the liquid nitrogen, then move the hoisting assembly to hoist the valve seat into the valve cavity of the valve body, and make the second longitudinal beam of the hoisting assembly abut against the limiting block. Under the guidance of the limiting block, the valve seat is hoisted to the predetermined assembly position. Step S5: Control the lifting assembly to slowly lower the valve seat to the annular position of the mounting groove, so that the mounting inclined surface on the valve seat contacts the mounting groove, and then remove the flexible steel cable; Step S6: Place the support head at the center of the lifting plate, then control the push assembly to move so that the working end of the push assembly abuts against the support head and continuously outputs thrust, and finally assemble the valve seat into the predetermined position in the mounting groove; Step S7: After the temperature of the valve seat returns to room temperature, remove the lifting plate and the four connecting plates in sequence.

10. The method of use as described in claim 9, characterized in that, Step S6 also includes the following steps: Step S61: Control the working end of the pushing assembly to abut against the support head; Step S62: Insert the support rod between the first crossbeam and the second crossbeam; Step S63: Control the pushing assembly to continuously output thrust until the valve seat is assembled to the predetermined position.

Images