A device for testing the crushing strength of a cable protection tube
By designing a cable protection pipe flattening strength testing device that includes a motor-driven screw and a stabilizing guide rail, the problem of pressure not being able to be applied vertically in the existing technology is solved, achieving high-precision pressure resistance evaluation and data accuracy, and is suitable for testing in different pipe diameters and temperature environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANJING ZHUOSHI ELECTRIC
- Filing Date
- 2025-07-11
- Publication Date
- 2026-08-04
AI Technical Summary
Existing cable protection pipe flattening strength testing devices lack a vertical guiding mechanism, which prevents the pressure from acting perpendicularly on the central axis of the pipe. This causes the test data to deviate from the true compressive strength performance, especially for non-metallic pipes such as PVC and HDPE pipes, where uneven stress distribution leads to premature failure.
A testing device was designed, comprising a worktable, mounting bracket, motor, bushing, screw, connecting plate, guide block, pressure plate, sliding frame, dial indicator, placement plate, adjustment assembly, and clamping assembly. The motor drives the screw mechanism to achieve vertical downward pressure, and combined with the stabilizing guide rail and guide block, it ensures that the pressure plate is vertical and without deviation. A dial indicator is provided to monitor displacement. It is compatible with different pipe diameters. The clamping assembly achieves flexible clamping through an electric cylinder and rubber pads. A constant temperature chamber is provided to simulate different temperature environments.
It achieves high-precision flattening strength testing, eliminates test data errors, provides original data benchmarks, is compatible with different pipe diameters, simulates actual environments, protects pipe bodies from damage, and provides high-precision compressive strength evaluation.
Smart Images
Figure CN224594344U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of cable protection, and in particular to a device for testing the flattening strength of cable protection pipes. Background Technology
[0002] Cables consist of a conductor (copper / aluminum), insulation layer, shielding layer, and sheath. They are used to transmit high-voltage electrical energy above 10kV and are core power transmission and distribution components of power systems. Cable protection pipes are metal or non-metal conduits laid around the cable. Common types include PVC plastic pipes, HDPE pipes, steel-reinforced armored pipes, epoxy resin pipes, and fiberglass pipes.
[0003] The purpose of the flattening strength test for cable protection pipes is to evaluate the deformation resistance and structural reliability of the protection pipes by simulating the external pressure during underground laying.
[0004] Currently, many traditional devices use hydraulic pressure or gravity weights to apply pressure, but the pressure head lacks a vertical guiding mechanism, making it prone to uneven loading and tilting. This results in the pressure not being applied perpendicularly to the central axis of the pipe, causing measured data to deviate from the true compressive strength. This is especially problematic for non-metallic pipes (such as PVC and HDPE), where uneven stress distribution can lead to premature failure.
[0005] To address this issue, a special device for testing the flattening strength of cable protection pipes was designed. Utility Model Content
[0006] In order to overcome the shortcomings of the existing technology, this utility model provides a cable protection pipe flattening strength testing device.
[0007] A cable protection pipe flattening strength testing device includes a workbench, a mounting frame, a motor, a bushing, a screw, a connecting plate, a guide block, a pressure plate, a sliding frame, a dial indicator, a placement plate, an adjustment assembly, and a clamping assembly. The mounting frame is located on the top of the workbench, and a motor with its output shaft facing downwards is mounted on top of the mounting frame. A reinforcing plate is located on the upper side of the mounting frame, and a bushing is rotatably connected to the middle of the reinforcing plate. The bushing is connected to the output shaft of the motor, and a screw is rotatably connected inside the bushing. A connecting plate is located at the bottom of the screw, and a stabilizing guide rail is located on the rear side of the mounting frame. A guide block is slidably connected to the stabilizing guide rail, and the guide block is connected to the side of the connecting plate. A pressure plate is provided at the bottom of the connecting plate. A matching guide rail is provided on the front side of the mounting bracket, and a sliding frame is slidably connected to the matching guide rail. A bearing rod is provided on the side of the sliding frame, and a dial indicator is installed on the bearing rod. A pull rope is provided at the bottom of the dial indicator, and the lower end of the pull rope is connected to the front side of the connecting plate. A through groove is opened in the middle of the worktable, and a placement plate is slidably connected in the through groove. An adjustment component is provided at the bottom of the worktable, which drives the placement plate to slide. A clamping component is provided at the top of the worktable.
[0008] More preferably, it also includes a temperature control chamber, with a temperature control chamber installed at the bottom of the workbench.
[0009] More preferably, the adjustment assembly includes a guide rod, a lead screw, and a knob. The guide rod is connected to one side of the bottom of the constant temperature chamber, and the lead screw is connected to the side of the bottom of the constant temperature chamber adjacent to the guide rod. A mating plate is provided on one side of the bottom of the placement plate. The mating plate is slidably connected to the guide rod and rotatably connected to the lead screw. A knob is rotatably connected to one side of the top of the worktable. The bottom of the knob rotates through the worktable and connects to the top of the lead screw.
[0010] More preferably, the clamping assembly includes an electric cylinder, a connecting block, a connecting rod, clamping plates, rubber pads, and a bidirectional drive guide rail. An electric cylinder with its telescopic end facing forward is installed at the middle of the rear of the worktable. A connecting block is provided on the telescopic end of the electric cylinder. Connecting rods are rotatably connected to both sides of the connecting block. Clamping plates are slidably connected to both sides of the through groove in the middle of the worktable. The upper side of each of the two clamping plates is rotatably connected to the corresponding connecting rod. Rubber pads are connected to the opposite ends of the two clamping plates. A bidirectional drive guide rail is installed on the front side of the top of the worktable. The front of each of the two clamping plates is slidably connected to the bidirectional drive guide rail.
[0011] More preferably, it also includes a baffle, which is rotatably connected to the bottom of the worktable on the side away from the knob. When the baffle slides, it can cover the through groove in the middle of the worktable, and the side of the baffle is exposed above the worktable.
[0012] More preferably, the baffle is provided with a push handle on the side exposed on the workbench, and the push handle is designed vertically.
[0013] The beneficial effects of this utility model are as follows: 1. The screw mechanism driven by the motor converts rotary motion into linear motion through the bushing. Combined with the rigid constraint of the stable guide rail and guide block, it ensures that the pressure plate is pressed down vertically without deviation, eliminating test data errors. The dial indicator directly monitors the displacement of the pressure plate by pulling the rope, forming a high-precision deformation-to-pressure curve, providing original data benchmark for evaluating the pressure resistance performance of the protective tube. The sliding fit design of the through groove and the placement plate is compatible with samples of different pipe diameters. The adjustment component controls the height of the placement plate by driving the screw through the knob, realizing the rapid centering of the sample center with the pressure plate. The bidirectional drive guide rail of the clamping component is linked with the electric cylinder, so that the clamping plate synchronously clamps the sample. The rubber pad adapts to the surface of the tube body, avoiding sample slippage or surface damage.
[0014] 2. A physical barrier is formed by covering the slot opening with a baffle, which, together with the push handle, enables quick opening and closing, effectively preventing debris from splashing during testing; when the motor is overloaded, the friction pair between the bushing and the screw slips and relieves the load, protecting the transmission mechanism; the constant temperature chamber isolates external temperature interference, ensuring the stability of the testing environment.
[0015] 3. By connecting the constant temperature chamber with the workbench through the slot, the underground laying temperature field (such as low temperature frozen soil or high temperature environment) can be simulated to test the coupling effect of temperature variables on the flattening strength of the pipe.
[0016] 4. The electric cylinder drives the bidirectional guide rail through the linkage mechanism, so that the clamping plates on both sides are clamped with constant force; the elastic deformation of the rubber pad compensates for the expansion of the tube under pressure, maintains the stability of the clamping force and protects the surface of the tube. Attached Figure Description
[0017] Figure 1 This is a three-dimensional structural diagram of the present invention.
[0018] Figure 2 This is a structural schematic diagram of the workbench, mounting frame, motor, and other components of this utility model.
[0019] Figure 3 This is a cross-sectional structural diagram of the electric cylinder, connecting block, and connecting rod of this utility model.
[0020] Figure 4 This is a cross-sectional structural diagram of the constant temperature chamber, placement plate, and guide rod of this utility model.
[0021] The following are the labels in the diagram: 1. Workbench, 2. Mounting bracket, 3. Motor, 4. Bushing, 5. Screw, 6. Connecting plate, 7. Guide block, 8. Pressure plate, 9. Sliding frame, 10. Dial indicator, 11. Electric cylinder, 12. Connecting block, 13. Connecting rod, 14. Clamping plate, 15. Rubber pad, 16. Two-way drive guide rail, 17. Constant temperature chamber, 18. Placement plate, 19. Guide rod, 20. Lead screw, 21. Knob, 22. Baffle. Detailed Implementation
[0022] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings.
[0023] Example: A device for testing the flattening strength of cable protection pipes, such as... Figures 1-4As shown, the device includes a workbench 1, a mounting frame 2, a motor 3, a bushing 4, a screw 5, a connecting plate 6, a guide block 7, a pressure plate 8, a sliding frame 9, a dial indicator 10, a placement plate 18, adjustment components, and clamping components. The workbench 1 serves as the basic platform for the entire testing device, supporting all functional components and providing a stable testing environment. A mounting frame 2 is mounted on top of the workbench 1, and a motor 3 with its output shaft facing downwards is mounted on top of the mounting frame 2. The motor 3 serves as the power source, providing stable rotational torque. A reinforcing plate is located on the upper side of the mounting frame 2, and a bushing 4 is rotatably connected to the middle of the reinforcing plate. The bushing 4 is connected to the output shaft of the motor 3, and a screw 5 is rotatably connected inside the bushing 4. A connecting plate 6 is located at the bottom of the screw 5. A stabilizing guide rail is located on the rear side of the mounting frame 2. A guide block 7 is slidably connected to the stabilizing guide rail. The guide block 7 is connected to the side of the connecting plate 6. A pressure plate 8 is provided at the bottom of the connecting plate 6. A matching guide rail is provided on the front side of the mounting bracket 2. A sliding frame 9 is slidably connected to the matching guide rail. A bearing rod is provided on the side of the sliding frame 9. A dial indicator 10 is installed on the bearing rod. A pull rope is provided at the bottom of the dial indicator 10. The lower end of the pull rope is connected to the front side of the connecting plate 6. The dial indicator 10 measures the displacement of the pressure plate 8 by the change in tension of the pull rope. When the protective tube undergoes plastic deformation, the pointer of the dial indicator 10 suddenly changes to form an obvious inflection point. A through groove is opened in the middle of the workbench 1. A placement plate 18 is slidably connected in the through groove. An adjustment component is provided at the bottom of the workbench 1. The adjustment component drives the placement plate 18 to slide. A clamping component is provided at the top of the workbench 1.
[0024] like Figure 1 , Figure 3 and Figure 4 As shown, it also includes a constant temperature chamber 17. The constant temperature chamber 17 is installed at the bottom of the workbench 1. The constant temperature chamber 17 controls the temperature field of the sample through the through groove in the middle of the workbench 1.
[0025] like Figure 1 and Figure 4 As shown, the adjustment assembly includes a guide rod 19, a lead screw 20, and a knob 21. The guide rod 19 is connected to one side of the bottom of the constant temperature chamber 17, and the lead screw 20 is connected to the side of the bottom of the constant temperature chamber 17 adjacent to the guide rod 19. A mating plate is provided on one side of the bottom of the placement plate 18. The mating plate is slidably connected to the guide rod 19 and rotatably connected to the lead screw 20. A knob 21 is connected to one side of the top of the workbench 1. The bottom of the knob 21 rotates through the workbench 1 and is connected to the top of the lead screw 20. By rotating the knob 21, the lead screw 20 is driven to rotate, so that the guide rod 19 drives the placement plate 18 to rise and fall to the test height.
[0026] like Figure 1 and Figure 3As shown, the clamping assembly includes an electric cylinder 11, a connecting block 12, a connecting rod 13, a clamping plate 14, a rubber pad 15, and a bidirectional drive guide rail 16. An electric cylinder 11 with its telescopic end facing forward is installed at the middle of the rear of the worktable 1. A connecting block 12 is provided on the telescopic end of the electric cylinder 11. Connecting rods 13 are rotatably connected to both sides of the connecting block 12. Clamping plates 14 are slidably connected to both sides of the through groove in the middle of the worktable 1. The upper side of each clamping plate 14 is rotatably connected to the corresponding connecting rod 13. Rubber pads 15 are glued to the opposite ends of the two clamping plates 14. The rubber pads 15 flexibly clamp the protective tube. A bidirectional drive guide rail 16 is installed on the front of the top of the worktable 1. The front of each clamping plate 14 is slidably connected to the bidirectional drive guide rail 16. The bidirectional drive guide rail 16 synchronously controls the movement of the clamping plates 14.
[0027] like Figure 1 and Figure 4 As shown, it also includes a baffle 22. The baffle 22 is rotatably connected to the bottom of the worktable 1 on the side away from the knob 21. When the baffle 22 slides, it can cover the through groove in the middle of the worktable 1. The side of the baffle 22 is exposed above the worktable 1. The side of the baffle 22 exposed on the worktable 1 is provided with a push handle. The push handle is designed to be vertical.
[0028] During the sample loading stage, the operator places the protective tube to be tested horizontally in the through slot of the workbench 1. By rotating the knob 21, the screw 20 mechanism is driven, causing the guide rod 19 to lift the placement plate 18 to the test height. The baffle 22 unfolds by pushing the handle to form a protective barrier to prevent the sample from accidentally falling off. The electric cylinder 11 of the clamping assembly pushes the connecting block 12 forward, and the connecting rod 13 mechanism causes the two clamping plates 14 to move synchronously along the bidirectional drive guide rail 16. After the rubber pad 15 contacts the tube body, it forms a flexible fixation to ensure the axial positioning accuracy of the sample. During the power transmission stage, after the motor 3 starts, the output shaft drives the bushing 4 to rotate. The internal threaded joint converts the vertical movement of the screw 5 into the vertical movement of the screw. The reinforcing plate enhances the support stability of the bushing 4 and prevents radial sway. The connecting plate 6 moves down along the stable guide rail under the drive of the screw 5. The guide block 7 eliminates lateral offset and ensures the perpendicularity of the movement trajectory of the pressure plate 8. At this time, the dial indicator 10 records the displacement of the connecting plate 6 in real time by pulling the rope, forming the reference data of the pressure to deformation curve. During the pressure application stage, the pressure plate 8 continues to press down after contacting the upper surface of the protective tube. The constant temperature chamber 17 controls the temperature field of the sample through the through groove. The placement plate 18 evenly transmits the pressure to the bottom of the tube. The mating plate in the adjustment assembly moves along the guide rail. The sliding rod 19 avoids testing errors caused by uneven loading. The bidirectional drive guide rail 16 maintains a constant clamping force on the clamping plate 14. The elastic deformation of the rubber pad 15 compensates for the radial expansion of the tube body under pressure. During the deformation monitoring stage, the sliding frame 9 moves down synchronously along the matching guide rail. The dial indicator 10 on the bearing rod measures the displacement of the pressure plate 8 by changing the tension of the pulling rope. When the protective tube undergoes plastic deformation, the pointer of the dial indicator 10 suddenly changes, forming a clear inflection point. The linkage 13 mechanism of the clamping assembly automatically adjusts the opening and closing degree of the clamping plate 14, preventing sample slippage and avoiding excessive constraint from affecting the deformation data. The safety protection mechanism baffle 22 is in place throughout the test. The shielding of the slot opening prevents fragments from splashing. The closed structure of the constant temperature chamber 17 maintains temperature stability. The rubber pad 15 generates buffer deformation under extreme pressure to protect the measuring mechanism from impact. When the motor 3 is overloaded, the friction pair between the bushing 4 and the screw 5 can slip and unload, avoiding mechanical damage. After the reset test is completed, the motor 3 reverses, the screw 5 drives the connecting plate 6 to move upward to reset, the dial indicator 10 pointer returns to zero, the electric cylinder 11 retracts and pulls the clamping plate 14 to release the sample, the knob 21 rotates in the opposite direction to lower the placement plate 18 to the loading and unloading position, and the baffle 22 retracts to remove the sample, completing the complete test cycle.
[0029] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.
Claims
1. A device for testing the crushing strength of a cable protection pipe, comprising a worktable (1), characterized in that, It also includes a mounting bracket (2), a motor (3), a bushing (4), a screw (5), a connecting plate (6), a guide block (7), a pressure plate (8), a sliding frame (9), a dial indicator (10), a placement plate (18), an adjustment assembly, and a clamping assembly. The top of the worktable (1) is equipped with a mounting bracket (2), and the top of the mounting bracket (2) is equipped with a motor (3) with its output shaft facing downwards. The upper side of the mounting bracket (2) is equipped with a reinforcing plate, and the middle of the reinforcing plate is rotatably connected to a bushing (4). The bushing (4) is connected to the output shaft of the motor (3). The bushing (4) is rotatably connected to a screw (5), and the bottom of the screw (5) is equipped with a connecting plate (6). The rear side of the mounting bracket (2) is equipped with a stabilizing guide rail. A guide block (7) is slidably connected to the stable guide rail. The guide block (7) is connected to the side of the connecting plate (6). A pressure plate (8) is provided at the bottom of the connecting plate (6). A matching guide rail is provided on the front side of the mounting bracket (2). A sliding frame (9) is slidably connected to the matching guide rail. A bearing rod is provided on the side of the sliding frame (9). A dial indicator (10) is installed on the bearing rod. A pull rope is provided at the bottom of the dial indicator (10). The lower end of the pull rope is connected to the front side of the connecting plate (6). A through groove is provided in the middle of the workbench (1). A placement plate (18) is slidably connected in the through groove. An adjustment component is provided at the bottom of the workbench (1). The adjustment component drives the placement plate (18) to slide. A clamping component is provided at the top of the workbench (1).
2. The cable protection pipe flattening strength testing device as described in claim 1, characterized in that, It also includes a constant temperature chamber (17), and a constant temperature chamber (17) is installed at the bottom of the workbench (1).
3. A cable protection pipe crush strength testing apparatus as claimed in claim 2, wherein, The adjustment assembly includes a guide rod (19), a lead screw (20), and a knob (21). The guide rod (19) is connected to one side of the bottom of the constant temperature chamber (17). The lead screw (20) is connected to the side of the bottom of the constant temperature chamber (17) adjacent to the guide rod (19). A mating plate is provided on one side of the bottom of the placement plate (18). The mating plate is slidably connected to the guide rod (19) and rotatably connected to the lead screw (20). A knob (21) is rotatably connected to one side of the top of the workbench (1). The bottom of the knob (21) rotates through the workbench (1) and is connected to the top of the lead screw (20).
4. A cable protection pipe crush strength testing apparatus as claimed in claim 3, wherein, The clamping assembly includes an electric cylinder (11), a connecting block (12), a connecting rod (13), a clamping plate (14), a rubber pad (15), and a bidirectional drive rail (16). An electric cylinder (11) with its telescopic end facing forward is installed in the middle of the rear of the worktable (1). A connecting block (12) is provided on the telescopic end of the electric cylinder (11). A connecting rod (13) is rotatably connected to both sides of the connecting block (12). A clamping plate (14) is slidably connected to both sides of the through groove in the middle of the worktable (1). The upper side of the two clamping plates (14) is rotatably connected to the corresponding connecting rod (13). A rubber pad (15) is connected to the opposite end of the two clamping plates (14). A bidirectional drive rail (16) is installed on the front side of the top of the worktable (1). The front of the two clamping plates (14) is slidably connected to the bidirectional drive rail (16).
5. A cable protection pipe crush strength testing apparatus as claimed in claim 4, wherein, It also includes a baffle (22). The baffle (22) is rotatably connected to the bottom of the worktable (1) away from the knob (21). When the baffle (22) slides, it can cover the through groove in the middle of the worktable (1), and the side of the baffle (22) is exposed above the worktable (1).
6. A cable protection pipe crush strength testing apparatus as claimed in claim 5, wherein, The baffle (22) is exposed on the side of the workbench (1) and has a push handle with a vertical design.