Large compensation amount z-shaped compression spring test bench

Abstract

The present application relates to the field of spring test, disclose a kind of big compensation amount Z-shaped compression spring test bench, including from top to bottom upper support plate, backing plate, hydraulic jack and lower support plate, is equipped with connecting piece for connecting upper support plate and lower support plate, multiple groups of hydraulic jack is evenly distributed in the lower side of backing plate for providing pressure, also include the same number of pressure sensor and displacement sensor as hydraulic jack, pressure sensor is arranged between hydraulic jack and backing plate, displacement sensor is used to measure the displacement distance of backing plate.To provide a kind of device capable of detecting the performance of big compensation amount Z-shaped compression spring.

Description

Technical Field

[0001] This invention relates to the field of spring testing, and specifically to a test bench for Z-shaped compression springs with large compensation. Background Technology

[0002] The Z-shaped compression spring is a Z-shaped annular component made of special martensitic stainless steel, designed for long-term operation in extremely harsh operating environments, such as high temperature, high pressure, high radiation, and corrosive conditions. Therefore, high requirements are placed on the tensile properties, ductility, impact toughness, surface hardness, and corrosion resistance of this compression spring material. With dimensions approaching 3 meters, this compression spring can be used in nuclear power plant reactors. It is a crucial component within the reactor's internal structure, its main function being to provide sufficient preload pressure to the reactor internal components via the reactor pressure vessel's main bolts, compensating for axial manufacturing errors and thermal expansion differences in the pressure vessel, basket flange, and upper support flange, and preventing axial movement and vibration of the basket assembly and upper support assembly. Due to its special function, its performance must be tested before use. However, currently, it is not possible to perform performance testing on large compression springs domestically. To solve this problem, a compression spring repeated loading test bench was invented. Summary of the Invention

[0003] The present invention aims to provide a test bench for Z-shaped compression springs with large compensation amount, so as to provide a device capable of testing the performance of Z-shaped compression springs with large compensation amount.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a large compensation Z-shaped compression spring test bench, comprising an upper support plate, a liner plate, hydraulic jacks, and a lower support plate from top to bottom, and a connecting piece for connecting the upper support plate and the lower support plate. Multiple sets of hydraulic jacks are circumferentially distributed below the liner plate to provide pressure. The test bench also includes pressure sensors and displacement sensors of the same number as the hydraulic jacks. The pressure sensors are located between the hydraulic jacks and the liner plate, and the displacement sensors are used to measure the displacement distance of the liner plate.

[0005] The beneficial effects of this plan are:

[0006] 1. Performance testing of large-diameter Z-shaped compression springs is possible. These Z-shaped springs are made of special martensitic stainless steel, which possesses high hardness and toughness, as well as good corrosion resistance, heat resistance, cold deformation resistance, and vibration damping performance. They are well-suited for use in nuclear power plant reactors and are typically required to operate safely for over 40 years. However, their high hardness and large diameter make testing challenging. In this technical solution, the upper and lower support plates are connected together as a rigid unit. Multiple hydraulic jacks apply pressure to the compression spring through the liner, causing the Z-shaped compression spring to deform under internal forces within the rigid structure. Because the action and reaction forces are equal in magnitude and opposite in direction, and because the upper and lower support plates form a rigid unit that does not deform, displacement sensors measure the displacement distance of the liner, and pressure sensors measure the pressure on the spring. This allows for precise measurement of the compression spring's preload compensation and the relationship between the preload and the applied force, ensuring accurate performance measurement and further guaranteeing the stability and reliability of the reactor operation. The reason for setting up multiple sets of hydraulic jacks is twofold. Firstly, the clamping spring has a ring-shaped structure with a large diameter, making it difficult for a single hydraulic jack to apply pressure evenly, thus hindering accurate measurement. Secondly, the clamping spring has high hardness and toughness, making it difficult for ordinary hydraulic jacks to provide sufficient pressure. Furthermore, the clamping spring often requires repeated testing, so setting up multiple sets of hydraulic jacks also helps improve testing efficiency.

[0007] 2. This solution enables uniform pressure application to the compression spring, ensuring the accuracy of the measurement results. A liner is placed between the hydraulic jack and the spring being tested. Firstly, the liner averages the clamping force from multiple hydraulic jacks, preventing even slight variations in pressure from a single jack from significantly affecting or influencing the test results. Furthermore, the solution incorporates multiple pressure and displacement sensors; by calculating the average value, the accuracy of the results is guaranteed. Secondly, the liner prevents the pressure sensors from directly contacting the compression spring, protecting the spring's surface.

[0008] Preferably, as an improvement, the number of hydraulic jacks is six, and the number of connecting parts around each hydraulic jack is two sets. This configuration strengthens the structural strength of the test bench. When the hydraulic jacks are working, the connecting parts reinforce the connection between the upper and lower support plates, preventing localized deformation of the upper and lower support plates due to hydraulic pressure, which would affect the accuracy of the test results. Furthermore, the advantage of having six sets of hydraulic jacks is that, firstly, the six sets of hydraulic jacks are evenly distributed circumferentially, ensuring uniform pressure on the compression springs and improving the reliability of the test data; secondly, the total pressure provided by the six sets of hydraulic jacks can exceed 10,000 kN, fully capable of simulating the working environment of the compression springs.

[0009] Preferably, as an improvement, one end of the connector is fixedly connected to the lower support plate, and the other end of the connector is threaded with two nuts for fixing the upper support plate. By making the other end of the connector threaded and connected with two nuts, on the one hand, the space between the upper and lower support plates can be adjusted to meet the needs of different specifications of Z-shaped compression springs with varying thicknesses; on the other hand, fixing the upper support plate with two nuts better ensures the stability of the test bench structure, making it less prone to loosening when the upper support plate is under stress, and ensuring reliable repeated data acquisition.

[0010] Preferably, as an improvement, it also includes a screw plug and a pressure sensor pad. The pressure sensor has a threaded hole, and the screw plug is threaded into the threaded hole. The upper end of the screw plug contacts the lower surface of the liner. The pressure sensor pad is located below the pressure sensor and is fixedly connected to the pressure sensor. By setting the screw plug to contact the lower surface of the liner, on the one hand, the height of the screw plug can be adjusted by rotating it during installation, making it easy to adjust the height of all screw plugs to the same level to ensure the stability of the test results. On the other hand, it can prevent the liner from being damaged due to uneven stress, which would affect the strength of the liner. The pressure sensor pad can protect the pressure sensor and extend the service life of the device.

[0011] Preferably, as an improvement, the lower surface of the upper support plate is provided with a first annular protrusion, and the upper surface of the liner is provided with a second annular protrusion. The first and second annular protrusions limit the movement of the compression spring. This design improves the accuracy of the compression spring's position, thereby ensuring the validity of the test results. During use, the compression spring will not shift left or right under force due to the limiting effect of the upper support plate and the liner.

[0012] Preferably, as an improvement, the pressure sensor pad has a circular groove for positioning and mounting the pressure sensor. This design facilitates the installation of the pressure sensor within the groove during assembly, ensuring the sensor is placed in the designated position each time, thus improving the reliability of data acquisition.

[0013] Preferably, as an improvement, the upper support plate, the liner plate, and the lower support plate are all annular. With this arrangement, since the Z-shaped compression spring has an annular structure, the production cost of the test bench can be reduced. Attached Figure Description

[0014] Figure 1 This is a cross-sectional view of an embodiment of the present invention;

[0015] Figure 2 This is a top view of an embodiment of the present invention. Detailed Implementation

[0016] The following detailed description illustrates the specific implementation method:

[0017] The reference numerals in the accompanying drawings include: upper support plate 1, lower support plate 2, hydraulic jack 3, liner plate 4, nut 5, bolt 6, pressure sensor 7, displacement sensor 8, pressure sensor pad 9, compression spring 10, screw plug 11, mounting plate 12, washer 13, power system 14.

[0018] Example

[0019] The implementation examples are basically as follows Figures 1-2 As shown, Figure 1 The large-compensation Z-shaped compression spring test bench shown includes, from top to bottom, an upper support plate 1, a liner plate 4, hydraulic jacks 3, and a lower support plate 2. In this embodiment, there are six hydraulic jacks 3, which are evenly distributed circumferentially below the liner plate 4 to provide pressure. Figure 2As shown, two sets of bolts 6 are set around the hydraulic jack 3 to connect the upper support plate 1 and the lower support plate 2, which can strengthen the structural strength of the test bench. When the hydraulic jack 3 is working, the two sets of bolts 6 strengthen the connection between the upper support plate 1 and the lower support plate 2, so as to avoid the upper support plate 1 and the lower support plate 2 from local deformation due to hydraulic pressure, which would affect the accuracy of the test results. It also includes the same number of pressure sensors 7 and displacement sensors 8 as the hydraulic jack 3. The pressure sensors 7 and displacement sensors 8 are evenly distributed around the upper support plate 1. The pressure sensors 7 are located between the hydraulic jack 3 and the liner 4 and can detect the pressure provided by the hydraulic jack 3 at that point. The displacement sensors 8 are used to measure the displacement distance of the liner 4 to test the compensation amount of the compression spring 10. A test hole is opened on the upper support plate 1. One end of the displacement sensor 8 is fixed to the upper surface of the upper support plate 1 by a bracket, and the other end of the displacement sensor 8 passes through the test hole and is connected to the liner 4. The detection end of the displacement sensor 8 is elastic and retractable. The displacement sensor 8 monitors the compensation amount of the compression spring 10 by detecting the relative distance between the liner 4 and the upper support plate 1. In this embodiment, the upper support plate 1, the liner 4 and the lower support plate 2 are all annular. This embodiment also includes a mounting plate 12. When in use, the lower support plate 2 and the mounting plate 12 are fixedly connected.

[0020] like Figure 1 As shown, in this embodiment, one end of the bolt 6 is fixedly connected to the lower support plate 2, and the other end of the bolt 6 is threaded and connected to two nuts 5 for fixing to the upper support plate 1. When fixing, a washer 13 is provided between the nut 5 and the upper support plate 1. This setting makes the upper support plate 1 less prone to loosening when under force, ensuring reliable repeated data acquisition. It also includes a screw plug 11 and a pressure sensor pad 9. In this embodiment, the pressure sensor 7 has a threaded hole, and the screw plug 11 is threadedly connected to the threaded hole. The upper end of the screw plug 11 contacts the lower surface of the liner plate 4. The pressure sensor pad 9 is located below the pressure sensor 7 to protect the pressure sensor 7. The pressure sensor pad 9 is fixedly connected to the pressure sensor 7 by an internal hexagon screw.

[0021] like Figure 1 As shown, in this embodiment, the lower surface of the upper support plate 1 is provided with a first annular protrusion, and the upper surface of the liner plate 4 is provided with a second annular protrusion. The first and second annular protrusions limit the compression spring 10 in the horizontal direction; as shown... Figure 1 As shown, a circular groove is opened on the lower surface of the pressure sensor pad 9 for positioning the pressure sensor 7; this embodiment also includes a power system 14 to provide power to the hydraulic jack 3.

[0022] The specific implementation process is as follows:

[0023] In use, the compression spring 10 is installed between the upper support plate 1 and the liner plate 4 by the limiting position of the first and second annular protrusions. Then, the nut 5 is tightened to fix the position of the upper support plate 1. Then, the power system 14 is started, and the six sets of hydraulic jacks 3 start working at the same time. The hydraulic jacks 3 apply pressure to the compression spring 10 through the liner plate 4. The liner plate 4 can average the clamping force of multiple hydraulic jacks 3 to avoid a small change in the pressure of one hydraulic jack 3 from having a large impact or error on the test results. At this time, the pressure sensor 7 accurately measures the pressure generated by each hydraulic jack 3, and the displacement sensor 8 measures the displacement of the liner plate 4. After calculating the average value of each set of pressure sensor 7 and displacement sensor 8, the preload of the compression spring 10, the maximum compensation amount, and the relationship between them can be detected, and accurate results can be obtained.

[0024] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A large compensation amount Z-shaped compression spring test bench, characterized in that: The system includes, from top to bottom, an upper support plate, a liner, hydraulic jacks, and a lower support plate. Connectors are provided to connect the upper and lower support plates. Multiple sets of hydraulic jacks are circumferentially distributed below the liner to provide pressure. The liner averages the clamping force of the multiple hydraulic jacks to avoid significant impact or error on test results due to slight pressure variations in any single hydraulic jack. It also includes pressure sensors and displacement sensors, the same number as the hydraulic jacks. The pressure sensors are located between the hydraulic jacks and the liner, accurately measuring the pressure generated by each hydraulic jack. The displacement sensors measure the displacement distance of the liner. Test holes are provided on the upper support plate. One end of the displacement sensor is fixed to the upper surface of the upper support plate by a bracket, and the other end of the displacement sensor passes through the test hole and is connected to the liner. The lower surface of the upper support plate is provided with a first annular protrusion, and the upper surface of the liner is provided with a second annular protrusion. The first annular protrusion and the second annular protrusion limit the compression spring in the horizontal direction. The pressure sensor pad has a circular groove for limiting the installation of the pressure sensor; The upper support plate, the liner plate, and the lower support plate are all annular.

2. The large compensation amount Z-shaped compression spring test bench according to claim 1, characterized in that: There are six hydraulic jacks, and two sets of connectors around each hydraulic jack.

3. The large compensation amount Z-shaped compression spring test bench according to claim 2, characterized in that: One end of the connector is fixedly connected to the lower support plate, and the other end of the connector is threaded with two nuts for fixing the upper support plate.

4. The large compensation amount Z-shaped compression spring test bench according to claim 3, characterized in that: It also includes a screw plug and a pressure sensor pad. The pressure sensor has a threaded hole, and the screw plug is threaded into the threaded hole. The upper end of the screw plug contacts the lower surface of the liner. The pressure sensor pad is located below the pressure sensor and is fixedly connected to the pressure sensor. By setting the screw plug to contact the lower surface of the liner, the height of the screw plug can be adjusted by rotating it during installation, so that the height of all screw plugs can be adjusted to the same level, thus ensuring the stability of the test results.

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