A cable buffer layer friction measurement device and method

Abstract

The present invention relates to a cable buffer layer friction measurement device and method, which is used to measure the friction between the cable core and the buffer layer in the tested cable. The device includes an electric push rod, a cable fixing mechanism and a frame supporting the entire device. The output end of the electric push rod is provided with a pressure sensor. The cable fixing mechanism includes a cable fixing base, a cable fixing assembly and a cable support assembly. The cable support assembly is used to horizontally support the tested cable. When the tested cable is supported by the cable support assembly, the output end of the electric push rod is directly opposite to the cable core. The cable fixing assembly is used to cooperate with the cable support assembly to fix the tested cable. The cable fixing base is also provided with a photoelectric sensor. Compared with the prior art, the present invention adopts a certain fixture design to fix the buffer layer of the tested cable, and the maximum axial static friction of the buffer layer is tested by the electric push rod, so as to achieve the characterization of the tightness between the cable core and the buffer layer.

Description

Technical Field

[0001] The invention relates to the field of friction force detection of power transmission cables, and in particular to a device and method for measuring the friction force of a cable buffer layer. Background Art

[0002] Transmission cables play a key role in urban power supply and economic development. In recent years, with the rapid development of urbanization, it is of great significance to ensure the safe and stable operation of cables.

[0003] my country's high-voltage power cables generally use a semi-conductive buffer layer as a structural layer for the transition from the insulation core to the metal sheath and grounding. The semi-conductive buffer layer is generally wrapped with a semi-conductive buffer tape, and the tightness of the semi-conductive buffer layer with the metal sheath is one of the important manifestations of its reliability, especially for the structure of the corrugated aluminum sheath, which is generally positively correlated with the transition conductivity.

[0004] During cable laying, the cable will be deformed when it is stretched from the bent state of the cable drum to the straight state on site, and the cable buffer layer will generate stress, which requires static friction of the cable buffer layer to offset the stress. The existing technical standards do not make relevant provisions for the detection and evaluation indicators of static friction of cable buffer layers. The experimental technology for detecting friction of cable buffer layers is not yet mature, and there is a lack of quantitative measurement and evaluation standards for cable performance. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide a cable buffer layer friction measurement device and method for detecting the static friction of the cable buffer layer.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A cable buffer layer friction measurement device is used to measure the friction between the cable core and the buffer layer of a measured cable. The device includes an electric push rod, a cable fixing mechanism and a frame supporting the entire device. The output end of the electric push rod is provided with a pressure sensor. The cable fixing mechanism includes a cable fixing base, a cable fixing assembly and a cable support assembly. The cable fixing assembly and the cable support assembly are both connected to the cable fixing base. The cable support assembly is used to horizontally support the measured cable. When the measured cable is supported by the cable support assembly, the output end of the electric push rod is directly opposite to the cable core. The cable fixing assembly is used to cooperate with the cable support assembly to fix the measured cable. The cable fixing base is also provided with a photoelectric sensor for detecting the movement of the cable core.

[0008] Further, the cable support assembly includes a first cable fixing block, a second cable fixing block, a screw and a screw driving member, the first cable fixing block and the second cable fixing block are both provided with a supporting inclined surface for supporting the measured cable, the first cable fixing block and the second cable fixing block are both connected to the screw, and the screw is driven by the screw driving member;

[0009] The cable fixing base is provided with a track for horizontal movement of the first cable fixing block and the second cable fixing block. Driven by the screw rod, the first cable fixing block and the second cable fixing block approach or move away from each other in the track. The first cable fixing block and the second cable fixing block form a movable V-shaped groove for supporting the cable under test and adjusting the height of the cable under test.

[0010] Furthermore, the screw rod is a positive and negative thread screw rod, provided with a positive thread portion and a negative thread portion, the first cable fixing block is connected to the positive thread portion, and the second cable fixing block is connected to the negative thread portion.

[0011] Furthermore, the screw drive member is a handle.

[0012] Furthermore, there are multiple cable support assemblies for horizontally supporting the tested cable.

[0013] Furthermore, the cable fixing assembly includes a first fixing rod, a second fixing rod and a wire clamp, the first cable fixing block and the second cable fixing block in each of the cable support assemblies are provided with a through hole, the first fixing rod passes through the through hole of the first cable fixing block in each of the cable support assemblies and abuts against the cable fixing base, the second fixing rod passes through the through hole of the second cable fixing block in each of the cable support assemblies and abuts against the cable fixing base; the wire clamp fixes the first fixing rod, the second fixing rod and the cable under test.

[0014] Furthermore, there are multiple wire cages.

[0015] Furthermore, the cable buffer layer friction force measuring device also includes a wire pressing block, and the output end of the electric push rod is connected to the pressure sensor and the wire pressing block in sequence.

[0016] Furthermore, the wire pressing block is a cylindrical structure.

[0017] Furthermore, the cable buffer layer friction force measuring device also includes a computer, and the electric push rod, pressure sensor and photoelectric sensor are all connected to the computer.

[0018] The present invention also provides a method for measuring the friction force of a cable buffer layer as described above, comprising the following steps:

[0019] First, the cable to be tested is placed on the cable support assembly, and the cable fixing assembly is used to relatively fix the cable to be tested and the cable fixing base; then the electric push rod is started to push the cable core to move until the photoelectric sensor detects a signal, and the value of the pressure sensor is recorded at this time as the friction measurement result of the cable buffer layer.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) The present invention aligns the cable core with the electric push rod through a cable support assembly, fixes the buffer layer of the tested cable through a cable fixing assembly, and pushes the cable core axially by the electric push rod to push the cable core out of the cable metal sheath of the buffer layer with a certain thrust; a pressure sensor installed in front of the electric push rod detects the force of the electric push rod pushing the cable, and when the cable core is pushed out of the cable metal sheath, the photoelectric sensor on the front side of the device is triggered by the cable core, and a corresponding test force value is obtained as the maximum static friction force of the semi-conductive buffer layer of the cable. The automation level is high, and the tightness between the insulating core and the metal sheath of the wrapped buffer tape is characterized.

[0022] (2) The first cable fixing block and the second cable fixing block with supporting inclined surfaces are driven by a lead screw to adjust the height of the measured cable. This setting is easy to adjust and ensures control accuracy.

[0023] (3) A forward and reverse threaded screw is used to simultaneously control the movement of the first cable fixing block and the second cable fixing block, thereby reducing the complexity of the structure.

[0024] (4) The first fixing rod and the second fixing rod fixed to the cable fixing block cooperate with a plurality of wire clamps to achieve reliable fixation of the tested cable.

[0025] (5) A wire pressing block is added at the contact point between the electric push rod and the cable core to increase the force-bearing area, which not only reduces the loss of the cable core and the pressure sensor, but also facilitates the pushing of the cable core.

[0026] (6) After the installation of the cable under test is completed, it can be automatically controlled by a computer to measure the friction force of the cable buffer layer. It has a high level of automation and is easy to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the cable buffer layer friction force measuring device of the present invention;

[0028] Figure 2 This is a schematic diagram of the cable support assembly of the present invention in use;

[0029] Figure 3 This is a control circuit diagram of the cable buffer layer friction force measuring device of the present invention;

[0030] In the figure, 1. electric push rod, 2. pressure sensor, 3. wire pressing block, 4. cable support assembly, 401. first cable fixing block, 402. second cable fixing block, 403. screw rod, 404. handle, 405. through hole, 5. cable fixing assembly, 501. first fixing rod, 502. wire lock, 6. tested cable, 601. buffer layer, 602. cable core, 7. photoelectric sensor, 8. frame, 9. cable fixing base, 10. computer. DETAILED DESCRIPTION

[0031] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0032] Example 1

[0033] The present embodiment provides a cable buffer layer friction force measuring device for measuring the friction force between the cable core 602 and the buffer layer 601 in the tested cable 6. A certain fixture design is used to fix a section of the finished cable sheath to be tested to the cable buffer layer friction force measuring device, so as to test the axial maximum static friction force of the cable semi-conductive buffer layer and characterize the tightness between the insulating core and the metal sleeve of the wrapped buffer tape.

[0034] like Figure 1 As shown, the cable buffer layer friction force measuring device of this embodiment includes an electric push rod 1, a cable fixing mechanism and a frame 8 supporting the entire device, the output end of the electric push rod 1 is provided with a pressure sensor 2, the cable fixing mechanism includes a cable fixing base 9, a cable fixing assembly 5 and a cable support assembly 4, the cable fixing assembly 5 and the cable support assembly 4 are both connected to the cable fixing base 9; the cable support assembly 4 is used to horizontally support the measured cable 6, when the measured cable 6 is supported by the cable support assembly 4, the output end of the electric push rod 1 is opposite to the cable core 602; the cable fixing assembly 5 is used to cooperate with the cable support assembly 4 to fix the measured cable 6, and the cable fixing base 9 is also provided with a photoelectric sensor 7 for detecting the movement of the cable core 602.

[0035] The various components and the measuring method of the device are described in detail below.

[0036] 1. Cable support assembly 4

[0037] like Figure 2As shown, the cable support assembly 4 includes a first cable fixing block 401, a second cable fixing block 402, a screw rod 403 and a screw rod driving member. The first cable fixing block 401 and the second cable fixing block 402 are both provided with a supporting inclined surface for supporting the tested cable 6. The first cable fixing block 401 and the second cable fixing block 402 are both connected to the screw rod 403, and the screw rod 403 is driven by the screw rod driving member.

[0038] The cable fixing base 9 is provided with a track for horizontal movement of the first cable fixing block 401 and the second cable fixing block 402. Driven by the screw rod 403, the first cable fixing block 401 and the second cable fixing block 402 move closer to or farther away from each other in the track. The first cable fixing block 401 and the second cable fixing block 402 form a movable V-groove for supporting the cable 6 under test and adjusting the height of the cable 6 under test.

[0039] Specifically, the inclination angles of the supporting slopes of the first cable fixing block 401 and the second cable fixing block 402 are the same, but the first cable fixing block 401 and the second cable fixing block 402 are symmetrically arranged, and there is a gap between them. Under the drive of the screw rod 403, they can approach or move away from each other, thereby forming the movable V-groove.

[0040] When the first cable fixing block 401 and the second cable fixing block 402 are close to each other, their supporting inclined surfaces are close to each other, driving the cable under test 6 to rise; when the first cable fixing block 401 and the second cable fixing block 402 are away from each other, their supporting inclined surfaces are away from each other, driving the cable under test 6 to descend, thereby achieving height adjustment.

[0041] The screw rod 403 is a positive and negative thread screw rod, and is provided with a positive thread portion and a negative thread portion. The first cable fixing block 401 is connected to the positive thread portion, and the second cable fixing block 402 is connected to the negative thread portion.

[0042] In this embodiment, the screw drive member is a handle 404 , and the number of the cable support assemblies 4 is four, which are used to horizontally support the cable 6 under test.

[0043] 2. Cable support assembly 4

[0044] The cable fixing assembly 5 includes a first fixing rod 501, a second fixing rod and a wire lock 502. The first cable fixing block 401 and the second cable fixing block 402 in each cable support assembly 4 are provided with a through hole 405. The first fixing rod 501 passes through the through hole 405 of the first cable fixing block 401 in each cable support assembly 4 and abuts against the cable fixing base 9. The second fixing rod passes through the through hole 405 of the second cable fixing block 402 in each cable support assembly 4 and abuts against the cable fixing base 9. The wire lock 502 is fixedly connected to the first fixing rod 501, the second fixing rod and the cable 6 under test.

[0045] In this embodiment, there are three wire clamps 502 ; the cable fixing base 9 is provided with a baffle for fixing the photoelectric sensor 7 , and the first fixing rod 501 and the second fixing rod are close to the photoelectric sensor 7 at one end thereof and abut against the baffle of the cable fixing base 9 .

[0046] 3. Other components

[0047] The cable buffer layer friction force measuring device also includes a wire pressing block 3, and the output end of the electric push rod 1 is connected to the pressure sensor 2 and the wire pressing block 3 in sequence.

[0048] The wire pressing block 3 is a cylindrical structure.

[0049] The cable buffer layer friction force measuring device also includes a computer 10 , and the electric push rod 1 , the pressure sensor 2 and the photoelectric sensor 7 are all connected to the computer 10 .

[0050] 4. Measurement method of cable buffer layer friction force measurement device

[0051] This embodiment also provides a measurement method of the cable buffer layer friction force measurement device, which can be summarized as follows:

[0052] First, the cable 6 to be tested is placed on the cable support assembly 4, and the cable fixing assembly 5 is used to relatively fix the cable 6 to the cable fixing base 9; then the electric push rod 1 is started to push the cable core 602 to move until the photoelectric sensor 7 detects a signal. At this time, the value of the pressure sensor 2 is recorded as the friction measurement result of the cable buffer layer 601.

[0053] The specific implementation includes the following steps:

[0054] like Figure 2 As shown, place the cable under test on two cable fixing blocks (i.e., the first cable fixing block and the second cable fixing block). The distance between the two cable fixing blocks is adjusted by rotating the handle to drive the positive and negative threaded screws. The height of the cable under test is adjusted according to the distance between the two cable fixing blocks until the height of the cable core reaches the center of the electric push rod.

[0055] like Figure 1 As shown, pass the wire clamp through the fixing rods on the two cable fixing blocks and the cable under test, and fix the cable under test to the two cable fixing blocks to ensure that the cable under test cannot be pushed.

[0056] like Figure 1 As shown, the electric push rod is started, and the electric push rod drives the pressure sensor and the wire pressing block to press onto the cable core of the tested cable. When the tested cable core is pushed, the photoelectric sensor is triggered to stop the test.

[0057] like Figure 3As shown in the figure, the electric push rod, pressure sensor and photoelectric sensor are controlled by a computer. When the computer issues a command to start the test, the electric push rod slowly applies pressure to push the cable core under test and records the pressure data sent back by the pressure sensor. When the photoelectric sensor is triggered, the electric push rod stops advancing, and the current pressure data is the value of the maximum static friction of the cable buffer layer.

[0058] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A cable buffer layer friction measurement device, used to measure the friction between a cable core (602) and a buffer layer (601) in a measured cable (6), the device comprising an electric push rod (1), a cable fixing mechanism and a frame (8) supporting the entire device, characterized in that: The output end of the electric push rod (1) is provided with a pressure sensor (2); the cable fixing mechanism comprises a cable fixing base (9), a cable fixing assembly (5) and a cable supporting assembly (4); the cable fixing assembly (5) and the cable supporting assembly (4) are both connected to the cable fixing base (9); the cable supporting assembly (4) is used to horizontally support the cable (6) under test; when the cable (6) under test is supported by the cable supporting assembly (4), the output end of the electric push rod (1) faces the cable core (602); the cable fixing assembly (5) is connected to the cable supporting assembly (4) and fixes the cable (6) under test; the cable fixing base (9) is also provided with a photoelectric sensor (7) for detecting the movement of the cable core (602); The cable support assembly (4) comprises a first cable fixing block (401), a second cable fixing block (402), a screw rod (403) and a screw rod driving member, the first cable fixing block (401) and the second cable fixing block (402) are both provided with a supporting inclined surface for supporting the measured cable (6), the first cable fixing block (401) and the second cable fixing block (402) are both connected to the screw rod (403), and the screw rod (403) is driven by the screw rod driving member; The first cable fixing block (401) and the second cable fixing block (402) form a movable V-shaped groove for supporting the tested cable (6) and adjusting the height of the tested cable (6); the cable fixing base (9) is provided with a track for the first cable fixing block (401) and the second cable fixing block (402) to move horizontally; the first cable fixing block (401) and the second cable fixing block (402) are driven by the screw rod (403) to move closer to or farther from each other in the track; The cable buffer layer friction force measuring device also includes a wire pressing block (3), and the output end of the electric push rod (1) is connected to the pressure sensor (2) and the wire pressing block (3) in sequence.

2. A cable buffer layer friction force measuring device according to claim 1, characterized in that: The screw rod (403) is a positive and negative thread screw rod, provided with a positive thread portion and a negative thread portion, the first cable fixing block (401) is connected to the positive thread portion, and the second cable fixing block (402) is connected to the negative thread portion.

3. A cable buffer layer friction force measuring device according to claim 1, characterized in that: The screw drive member is a handle (404).

4. A cable buffer layer friction force measuring device according to claim 1, characterized in that: The cable support components (4) are multiple in number and are used to horizontally support the tested cable (6).

5. A cable buffer layer friction force measuring device according to claim 4, characterized in that: The cable fixing assembly (5) comprises a first fixing rod (501), a second fixing rod and a wire clamp (502); the first cable fixing block (401) and the second cable fixing block (402) in each of the cable support assemblies (4) are provided with a through hole (405); the first fixing rod (501) passes through the through hole (405) of the first cable fixing block (401) in each of the cable support assemblies (4) and abuts against the cable fixing base (9); the second fixing rod passes through the through hole (405) of the second cable fixing block (402) in each of the cable support assemblies (4) and abuts against the cable fixing base (9); the wire clamp (502) fixes the tested cable (6) on the first fixing rod (501) and the second fixing rod.

6. A cable buffer layer friction force measuring device according to claim 5, characterized in that: The number of the wire clamps (502) is multiple.

7. A cable buffer layer friction force measuring device according to claim 1, characterized in that: The cable buffer layer friction force measuring device also includes a computer (10), and the electric push rod (1), the pressure sensor (2) and the photoelectric sensor (7) are all connected to the computer (10).

8. A method for measuring the friction force of a cable buffer layer as claimed in claim 1, characterized in that: The following steps are involved: First, the cable to be tested (6) is placed on the cable support assembly (4), and the cable fixing assembly (5) is used to relatively fix the cable to be tested (6) and the cable fixing base (9); then, the electric push rod (1) is started to push the cable core (602) to move until the photoelectric sensor (7) detects a signal, and at this time, the value of the pressure sensor (2) is recorded as the friction measurement result of the cable buffer layer (601).

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