Pull rod cryogenic testing device

Abstract

This utility model relates to the field of pull rod testing technology, and more particularly to a low-temperature pull rod testing device, comprising a main body, a coolant pool, and a first pull rod seat and a second pull rod seat disposed within the coolant pool. The second pull rod seat can move in a direction away from or towards the first pull rod seat. Both the first and second pull rod seats are provided with multiple mounting slots. A coolant pool is fixed to one end of the main body, and a lifting mechanism and a servo motor with a transmission connection are fixed externally to the other end. The lifting rod of the lifting mechanism is horizontally positioned; the end of the lifting rod is fixedly connected to the second pull rod seat via a tensile testing instrument. A waste liquid pool is located below the coolant pool, and an absorbent layer is laid inside the waste liquid pool. When using this utility model's low-temperature pull rod testing device, multiple pull rods can be tested simultaneously. Furthermore, by setting the required tensile force and turning on the servo motor, one-button start is achieved, providing a continuous and stable tensile force to the pull rod under test. It has advantages such as saving time and effort, saving liquid nitrogen, and high testing efficiency.

Description

Technical Field

[0001] This utility model relates to the field of pull rod testing technology, and in particular to a pull rod low temperature testing device. Background Technology

[0002] The tie rod is a crucial component in a superconducting magnet. Its mass determines the distance between the magnet's cylinders. In cryogenic environments, if the tie rod's performance deteriorates, the carbon fiber may detach from the screw head, leading to a decrease in magnet performance and, in severe cases, loss of superconductivity and significant damage.

[0003] Tensile testing of tie rods is a crucial step in verifying their quality. Tie rod testing is divided into room temperature tensile testing and liquid nitrogen cryogenic tensile testing. Room temperature testing requires applying a continuous and stable tensile force to the tie rod and maintaining it for a period of time, then releasing the force and observing the tie rod's condition after the force is released. Cryogenic testing requires placing the tie rod in a low-temperature environment, applying a continuous and stable tensile force to it and maintaining it for a period of time, then releasing the force and observing the tie rod's condition after the force is released.

[0004] Chinese utility model patent CN219084640U discloses an immersion-type pull rod tensile testing device. This device can only test one pull rod at a time, resulting in low testing efficiency and high liquid nitrogen consumption. Furthermore, it requires manual rotation of a handwheel to apply the tensile force, necessitating continuous observation of the force during room temperature testing and constant handwheel rotation to maintain a constant force. This device suffers from drawbacks such as low testing efficiency, high liquid nitrogen consumption, time-consuming and labor-intensive processes, and unstable tensile force. Moreover, during low-temperature tensile testing of pull rods, the low temperature of the coolant pool causes large gas molecules in the air to liquefy and adhere to the outside of the coolant pool. As the liquid accumulates, droplets fall onto the workbench or the floor where the device is placed, causing varying degrees of frost damage to the workbench or floor. Long-term use can lead to some degree of damage to the workbench or floor.

[0005] Therefore, designing a low-temperature testing device for a pull rod has become a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0006] The technical problem this utility model aims to solve is to provide a low-temperature testing device for pull rods, which can complete the testing of multiple pull rods at once. When using it, the required pulling force can be set and the servo motor can be turned on to achieve one-button start and provide a continuous and stable pulling force to the pull rod under test. It has the advantages of saving time and effort, saving liquid nitrogen, and high testing efficiency.

[0007] To solve the above problems, the technical solution adopted by this utility model is as follows: A low-temperature testing device for a pull rod includes a coolant pool and a first pull rod seat and a second pull rod seat spaced apart inside the coolant pool. The second pull rod seat can move in a direction away from or towards the first pull rod seat. Both the first and second pull rod seats are provided with multiple mounting slots for fixing the ends of the pull rods. The number of mounting slots on the first and second pull rod seats is equal, and their positions correspond one-to-one.

[0008] As an improvement, it also includes a main body; the coolant pool is fixed to the inner side of one end of the main body, and an elevator and a servo motor connected to the elevator are fixed to the outer side of the other end of the main body; the lifting rod of the elevator is set horizontally; one end of the lifting rod extends into the inner side of the main body and is fixedly connected to the second tie rod seat through a tensile tester; when the lifting rod of the elevator moves horizontally, it drives the tensile tester and the second tie rod seat to move horizontally.

[0009] As an improvement, the end of the first pull rod seat is provided with a first connecting shaft, which passes through the coolant pool and is fixedly connected to the body.

[0010] As an improvement, a positioning plane is machined on the first connecting shaft through the coolant pool and the body, and both the coolant pool and the body are provided with through holes that are adapted to the size and shape of the first connecting shaft.

[0011] As an improvement, the end of the second tie rod seat is provided with a second connecting shaft, which extends to the outside of the coolant pool and is fixedly connected to the tensile tester.

[0012] As an improvement, both the first and second pull rod seats are box-shaped with an open top, and multiple mounting slots are respectively provided on the top of the side wall of the first pull rod seat and the top of the side wall of the second pull rod seat.

[0013] As an improvement, vacuum sealant is applied to the locations on both the first and second connecting shafts that penetrate the coolant pool.

[0014] As an improvement, a waste liquid pool is provided below the coolant pool, and an absorbent layer is laid in the waste liquid pool.

[0015] The present invention adopts the above technical solution and has the following advantages compared with the prior art: When using this low-temperature testing device for tie rods, simply set the required tensile force and turn on the servo motor for one-button start, providing a continuous and stable tensile force to the tie rod under test. The servo motor automatically compensates for the unloading caused by the elongation of the tie rod under stress, intelligently maintaining the force state and saving time; no manual intervention is required. Furthermore, it can complete the testing of multiple tie rods at a time, saving time and liquid nitrogen, and saving both time and effort.

[0016] Vacuum sealing mud is applied to the locations on both the first and second connecting shafts that penetrate the coolant pool. The vacuum sealing mud can be used to seal the connection between the first connecting shaft and the coolant pool, and between the second connecting shaft and the coolant pool.

[0017] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a low-temperature testing device for a pull rod according to the present invention; Figure 2 This is a three-dimensional schematic diagram of a low-temperature testing device for a pull rod according to the present invention; Figure 3 for Figure 1 AA section view in the middle; Figure 4 for Figure 1 Enlarged view of point D in the image; Wherein: 1-body, 2-coolant pool, 3-first tie rod seat, 4-second tie rod seat, 5-installation groove, 6-waste liquid pool, 7-liquid absorption layer, 8-lifting machine, 9-lifting rod, 10-servo motor, 11-tensile tester, 12-first connecting shaft, 13-second connecting shaft, 14-positioning plane, 15-tie rod. Detailed Implementation

[0019] Example

[0020] The tie rod for superconducting magnets is a rod composed of carbon fiber and stainless steel screw head. Under ultra-low temperature environment and certain tensile force, the carbon fiber and stainless steel screw head cannot be pulled apart. The tie rod in superconducting magnets plays the role of bearing load and connecting various components.

[0021] like Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, a low-temperature testing device for a pull rod includes a box-shaped body (1) with an open top, a coolant pool (2), and a first pull rod seat (3) and a second pull rod seat (4) spaced apart inside the coolant pool (2) for fixing the two ends of a pull rod 15. The second pull rod seat (4) can move away from or towards the first pull rod seat (3). Both the first pull rod seat (3) and the second pull rod seat (4) are provided with multiple mounting slots (5) for fixing the ends of the pull rod; the number of mounting slots (5) on the first pull rod seat (3) and the second pull rod seat (4) are equal, and their positions correspond one-to-one. When using this low-temperature testing device to perform a tensile test on a pull rod 15, multiple pull rods 15 can be tested at once. In this embodiment, two pull rods 15 are tested at once, and the number of mounting slots (5) on the first pull rod seat (3) and the second pull rod seat (4) are both two. In actual use, the number of mounting slots (5) can be set according to the number of pull rods 15 tested at once.

[0022] The coolant pool (2) is fixed to the inner side of one end of the main body (1), and the elevator (8) and the servo motor (10) connected to the elevator (8) are fixed to the outer side of the other end of the main body (1). The lifting rod (9) of the elevator (8) is set horizontally. A clearance hole is provided on the main body (1) at the position corresponding to the lifting rod (9). One end of the lifting rod (9) passes through the clearance hole and extends to the inner side of the main body (1). The end of the lifting rod (9) is fixedly connected to the second tie rod seat (4) through the tensile tester (11). When the servo motor (10) drives the lifting rod (9) of the elevator (8) to move horizontally, the lifting rod (9) can drive the tensile tester (11) and the second tie rod seat (4) to move horizontally.

[0023] like Figures 1 to 4 As shown, the end of the first tie rod seat (3) is provided with a first connecting shaft (12), which passes through the coolant pool (2) and is fixedly connected to the body (1). In this embodiment, preferably, a positioning plane (14) is machined at the position on the first connecting shaft (12) that passes through the coolant pool (2) and the body (1). Both the coolant pool (2) and the body (1) are provided with through holes that are adapted to the size and shape of the first connecting shaft (12). The end of the first connecting shaft (12) is machined with a threaded section, and a nut is installed on the threaded section. The first tie rod seat (3), the coolant pool (2), and the body (1) are fixedly connected by the first connecting shaft (12) and the nut. During installation, the circumferential installation angle of the first tie rod seat (3) should be ensured so that the tie rod 15 is subjected to a tensile force along its axial direction during testing. When manufacturing this tie rod low temperature testing device, the positioning plane (14) can quickly and conveniently help the first tie rod seat (3) to be circumferentially positioned during installation.

[0024] The end of the second tie rod seat (4) is provided with a second connecting shaft (13), which extends to the outside of the coolant pool (2) and is fixedly connected to the tensile tester (11).

[0025] Both the first tie rod seat (3) and the second tie rod seat (4) are box-shaped with open tops. Multiple mounting slots (5) are respectively located on the top of the side wall of the first tie rod seat (3) and the top of the side wall of the second tie rod seat (4). Vacuum sealant is applied to the positions on the first connecting shaft (12) and the second connecting shaft (13) that penetrate the coolant pool (2). During the tie rod test, the tie rod 15 will elongate by about 1 mm under force; the vacuum sealant is used to seal between the first connecting shaft (12) and the coolant pool (2), and between the second connecting shaft (13) and the coolant pool (2). During the tie rod low-temperature test, the vacuum sealant can prevent coolant from flowing out of the coolant pool (2) and avoid coolant waste.

[0026] Below the coolant pool (2) is a waste liquid pool (6), and inside the waste liquid pool (6) is a liquid-absorbing layer (7). In this embodiment, preferably, the liquid-absorbing layer (7) is a cotton cloth layer. During the low-temperature tensile test of the pull rod, due to the low temperature of the coolant pool 2, the large molecular gas in the air will liquefy upon cooling and adhere to the outside of the coolant pool 2. As the liquid continues to accumulate, the droplets will drip into the waste liquid pool (6) and be absorbed by the liquid-absorbing layer (7), preventing liquid splashing. The waste liquid pool (6) and the liquid-absorbing layer (7) can effectively prevent the workbench or the ground on which the low-temperature test device for the pull rod is placed from freezing or being damaged.

[0027] This embodiment uses a 300mm long tie rod as an example to illustrate the testing process. When using this low-temperature testing device for the tie rod, the tie rod is first tested at room temperature. According to... Figure 3 The pull rod 15 is fixed between the first pull rod seat (3) and the second pull rod seat (4). The tensile force value of the tensile tester 11 is set, and the servo motor 10 is turned on. The servo motor 10 drives the lifting rod 9 of the elevator 8 to move. When the lifting rod 9 moves, it drives the tensile tester 11 and the second pull rod seat 4 to move horizontally and applies a tensile force to the pull rod 15 until the tensile force value measured by the tensile tester 11 reaches the set value, at which point the servo motor 10 stops working. For room temperature testing, the low-temperature testing device needs to continuously provide a tensile force of 0.45 tons to the pull rod 15 and maintain it for 10 minutes. Then, the force is released, and the state of the pull rod 15 is observed to determine whether the pull rod 15 is qualified at room temperature. If a change in the tensile force value is detected during the room temperature test, the servo motor 10 should be controlled to move until the tensile force value reaches the set value.

[0028] The second step is to conduct a low-temperature test on the pull rod 15. During the low-temperature test, the coolant pool (2) is filled with low-temperature coolant, immersing the pull rod 15 in the coolant. In the prior art, liquid nitrogen is often used as the coolant for low-temperature testing of the pull rod. During the low-temperature test of the pull rod 15, the pulling force provided by the testing device to the pull rod 15 needs to be adjusted to 0.38 tons. Then, liquid nitrogen is poured into the coolant pool (2) until it completely covers the pull rod 15. This is maintained for 10 minutes. Then, the force is released, and the state of the pull rod is observed to determine whether the pull rod 15 is qualified under low-temperature conditions. If a change in the pulling force value is detected during the low-temperature test, the servo motor 10 should be controlled to move until the pulling force value reaches the set value.

[0029] In practical applications, different tensile force values ​​and static holding times need to be set for different parameters when testing tie rods.

[0030] In summary, this utility model provides a cryogenic testing device for tie rods that can test multiple tie rods at once, shortening the testing cycle and reducing liquid nitrogen consumption for batch tie rods. Furthermore, by setting the required tensile force and activating the servo motor, it achieves one-button start-up, providing a continuous and stable tensile force to the tie rod under test. It offers advantages such as saving time and effort, conserving liquid nitrogen, and high testing efficiency, and is particularly suitable for tensile testing of tie rods with a total length not exceeding 400 mm.

[0031] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A low-temperature testing device for a pull rod, characterized in that: It includes a coolant reservoir (2) and a first pull rod seat (3) and a second pull rod seat (4) spaced apart inside the coolant reservoir (2), wherein the second pull rod seat (4) can move in a direction away from or close to the first pull rod seat (3); Both the first tie rod seat (3) and the second tie rod seat (4) are provided with multiple mounting slots (5) for fixing the ends of the tie rods; the number of mounting slots (5) on the first tie rod seat (3) and the second tie rod seat (4) is equal, and their positions correspond one to one.

2. The low-temperature testing device for the pull rod as described in claim 1, characterized in that: It also includes a body (1); the coolant pool (2) is fixed to the inner side of one end of the body (1), and an elevator (8) and a servo motor (10) connected to the elevator (8) are fixed to the outer side of the other end of the body (1); the lifting rod (9) of the elevator (8) is set horizontally; one end of the lifting rod (9) extends to the inner side of the body (1) and is fixedly connected to the second tie rod seat (4) through the tensile tester (11); when the lifting rod (9) of the elevator (8) moves horizontally, it drives the tensile tester (11) and the second tie rod seat (4) to move horizontally.

3. The low-temperature testing device for the pull rod as described in claim 2, characterized in that: The first connecting shaft (12) is provided at the end of the first tie rod seat (3). The first connecting shaft (12) passes through one end of the coolant pool (2) and is fixedly connected to the end of the body (1).

4. The low-temperature testing device for the pull rod as described in claim 3, characterized in that: The first connecting shaft (12) has a positioning plane (14) through the coolant pool (2) and the body (1). Both the coolant pool (2) and the body (1) have through holes that are adapted to the size and shape of the first connecting shaft (12).

5. The low-temperature testing device for the pull rod as described in claim 3, characterized in that: The end of the second tie rod seat (4) is provided with a second connecting shaft (13), which extends to the outside of the coolant pool (2) and is fixedly connected to the tensile tester (11).

6. The low-temperature testing device for the pull rod as described in claim 2, characterized in that: The first pull rod seat (3) and the second pull rod seat (4) are both box-shaped with open tops, and multiple mounting slots (5) are respectively set on the top of the side wall of the first pull rod seat (3) and the top of the side wall of the second pull rod seat (4).

7. The low-temperature testing device for the tie rod as described in claim 5, characterized in that: Vacuum sealant is applied to the positions on the first connecting shaft (12) and the second connecting shaft (13) that penetrate the coolant pool (2).

8. The low-temperature testing device for a pull rod as described in any one of claims 1 to 6, characterized in that: Below the coolant pool (2) is a waste liquid pool (6), and the waste liquid pool (6) is lined with a liquid absorption layer (7).

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