A power grid live working tool preventive test connecting tool and test method

Abstract

The application provides a power grid live working tool preventive test connecting tool, which comprises a U-shaped plate and a base; one end of the U-shaped plate is connected with a fixed end of a tensile load testing machine, and the other end of the U-shaped plate is detachably provided with the base; the base comprises a conventional base and a boss base; the contact surface of the conventional base and a linear tower head card test piece is a plane, which can simulate the stress state of the linear tower head card test piece on a cross arm; the contact surface of the boss base and a rectangular block of a single collecting screw rod test piece is provided with a boss, which can simulate the stress state of the single collecting screw rod test piece on a steel tower angle steel. Through the preventive test connecting tool, the bearing capacity of the linear tower head card and the single collecting screw rod can be evaluated, and the linear tower head card and the single collecting screw rod with defects can be exposed in advance, so as to provide an important guarantee for the safety of the power grid live working.

Description

Technical Field

[0001] This invention relates to a preventive testing connection fixture and testing method for live-line working tools in power grids. Background Technology

[0002] Linear insulator clamps are live-line working tools primarily used for replacing suspension insulators. Their function is to support heavy objects such as insulators and conductors, preventing them from falling or swaying, thus ensuring the safety of live-line work. Specifically, linear insulator clamps securely fix the insulator to the crossarm of the power grid tower by clamping the insulator's wire rope or grounding wire, preventing it from falling or swaying. The advantage of linear insulator clamps is that they can be installed and removed while the power is on, without needing to disconnect the power supply. This saves time and costs and improves work efficiency. Furthermore, the design of linear insulator clamps has undergone rigorous testing and verification to ensure their load-bearing capacity and stability, thereby guaranteeing the safety of live-line work. In summary, linear insulator clamps have significant application value in the replacement, maintenance, and repair of suspension insulators and are an indispensable tool in live-line work.

[0003] Single-twist lead screws are mainly used for replacing suspension insulators. When replacing suspension insulators, the new insulator needs to be installed on the suspension insulator string. However, the suspension insulator string is often located in a high position, making direct manual operation difficult. This is where single-twist lead screws come in; they achieve the purpose of installing the insulator by extending and retracting the screw. Single-twist lead screws have advantages such as being lightweight, flexible, and easy to operate, which can greatly improve work efficiency and safety.

[0004] According to the requirements of DL / T976-2017 "Preventive Testing Procedures for Live Working Tools, Devices and Equipment", load-bearing tools for live working need to undergo regular mechanical load tests. Currently, mechanical load tests on straight-line tower head clamps and single-lead rods are mainly carried out using tensile testing machines. The difficulty in mechanical load testing of straight-line tower head clamps and single-lead rods lies in the connection between the straight-line tower head clamps and single-lead rods and the testing equipment. Because in actual use, the stress support point of the straight-line tower head clamp is on the crossarm, and the stress support point of the single-lead rod is on the angle steel of the steel tower, mechanical load tests using ordinary ropes cannot simulate the actual stress state of the straight-line tower head clamps and single-lead rods due to the different stress support points of the straight-line tower head clamps and single-lead rods. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a preventive testing connection fixture and testing method for live-line working tools in power grids. This preventive testing connection fixture can fulfill the requirements of DL / T 976-2017 "Preventive Testing Procedures for Live-line Working Tools, Devices and Equipment" to assess the load-bearing capacity of straight-line tower head clamps and single-lead screws. For straight-line tower head clamps and single-lead screws with existing defects, it can expose these defects in advance, thus providing an important guarantee for ensuring the safe conduct of live-line working in power grids.

[0006] The technical solution adopted in this invention is as follows:

[0007] A preventive testing connection fixture for live-line working tools in power grids includes a U-shaped plate and a base. One end of the U-shaped plate can be connected to the fixed end of a tensile load testing machine. The U-shaped opening size of the U-shaped plate is the same as the width of the straight tower head clamp specimen. The other end of the U-shaped plate is detachably fitted with a base. The base includes a conventional base and a boss base. The contact surface between the conventional base and the straight tower head clamp specimen is planar, which can simulate the stress state of the straight tower head clamp specimen on the crossarm. The boss base has a boss on the contact surface with the rectangular block of the single-lead screw specimen, which can simulate the stress state of the single-lead screw specimen on the angle steel of the steel tower.

[0008] Furthermore, one end of the U-shaped plate is provided with a connecting hole, through which two U-shaped shackles are installed in sequence, and the U-shaped plate is connected to the fixed end of the tensile load testing machine through the U-shaped shackles.

[0009] Furthermore, the conventional base is installed in the opening of the U-shaped plate, and its two sides are provided with connecting ends that cooperate with the U-shaped plate. The conventional base is connected to the pin shaft of the U-shaped plate through the connecting ends on both sides. The conventional base is provided with an opening groove, and one side of the conventional base can contact the straight tower head clamp specimen, and the contact surface is a plane.

[0010] Furthermore, the boss base is installed in the opening of the U-shaped plate, and has connecting ends on both sides that cooperate with the U-shaped plate. The boss base is connected to the pin shaft of the U-shaped plate through the connecting ends on both sides. The boss base has an opening groove, and a boss of a rectangular block that cooperates with a single lead screw specimen is symmetrically provided on one side of the boss base.

[0011] Furthermore, both the conventional base and the boss base have locking pins in their opening slots.

[0012] A preventive testing method for a straight-line tower head clamp, the method being based on the aforementioned preventive testing connection fixture for live-line working tools in power grids, includes the following steps:

[0013] Step 1: Connect one end of the U-shaped plate to the fixed end of the tensile load testing machine using two U-shaped shackles, and install a conventional base on the other end of the U-shaped plate;

[0014] Step 2: Insert the linear tower head clamp specimen into the U-shaped opening of the U-shaped plate, while ensuring that the lead screw of the linear tower head clamp specimen is located in the opening groove of the conventional base.

[0015] Step 3: Lock the opening slot of the conventional base with a locking pin, and connect the screw end of the straight tower head specimen to the force application end of the tensile load testing machine through a single parallel hanging plate and a U-shaped shackle.

[0016] Step 4: Apply load using a tensile load testing machine. At this time, the straight tower head clamp contacts one end face of the conventional base, simulating the load-bearing capacity of the straight tower head clamp specimen when the force support point is on the crossarm in actual use.

[0017] A preventive testing method for a single-lead screw, the method being based on the aforementioned preventive testing connection fixture for live-line working tools in power grids, includes the following steps:

[0018] Step 1: Connect one end of the U-shaped plate to the fixed end of the tensile load testing machine through two U-shaped shackles, and install the boss base on the other end of the U-shaped plate;

[0019] Step 2: Install the rectangular block of the single lead screw specimen on the two bosses on one side of the boss base, while ensuring that the single lead screw specimen is located in the opening slot of the boss base.

[0020] Step 3: Lock the opening slot of the boss base with the locking pin, and connect it to the force application end of the tensile load testing machine at the end of the single screw rod specimen through a single parallel hanging plate and a U-shaped shackle.

[0021] Step 4: Apply load using a tensile load testing machine to simulate the load-bearing capacity of a single-lead screw specimen when the stress support point is on the angle steel of a steel tower in actual use.

[0022] The beneficial effects of this invention are:

[0023] This preventive testing fixture for live-line working tools is simple in structure and easy to manufacture. By replacing the conventional base or the boss base, it can simulate the crossarm or steel tower angle steel, thus enabling it to work with a tensile load testing machine to meet the actual stress conditions of straight tower head clamps and single lead screws in actual use. This preventive testing fixture for live-line working tools can meet the requirements of DL / T976-2017 "Preventive Testing Procedures for Live-line Working Tools, Devices and Equipment" to assess the load-bearing capacity of straight tower head clamps and single lead screws. For straight tower head clamps and single lead screws with existing defects, it can expose their defects in advance, thus providing an important guarantee for ensuring the safe conduct of live-line working on the power grid. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0025] Figure 1 This is a side view of the preventive test connection fixture of the present invention;

[0026] Figure 2 This is a schematic diagram of the end face structure of the preventive test connection tooling of the present invention;

[0027] Figure 3 This is the structural intent of the preventive test connection tooling boss base of the present invention;

[0028] Figure 4 This is a schematic diagram of the preventive test of the linear tower head clamp of the present invention;

[0029] Figure 5 This is a schematic diagram of the preventive test of the single-lead screw of the present invention;

[0030] In the figure, 1—U-shaped plate, 2—conventional base, 3—boss base, 4—connecting hole, 5—U-shaped shackle, 6—connecting end, 7—pin, 8—opening groove, 9—contact surface, 10—boss, 11—locking pin, 12—straight tower head clamp specimen, 13—straight tower head clamp specimen lead screw, 14—single parallel hanging plate, 15—fixed end of tensile load testing machine, 16—force application end of tensile load testing machine, 17—rectangular block of single lead screw specimen, 18—single lead screw specimen. Detailed Implementation

[0031] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] To address the issue that mechanical load tests on straight-line tower head clamps and single-lead rods using ordinary ropes cannot simulate their actual stress state, this embodiment provides a preventive testing connection fixture for live-line working tools in power grids. This fixture can meet the requirements of DL / T976-2017 "Preventive Testing Procedures for Live-line Working Tools, Devices and Equipment" to assess the load-bearing capacity of straight-line tower head clamps and single-lead rods. For straight-line tower head clamps and single-lead rods with existing defects, it can proactively expose their flaws, thus providing crucial protection for the safe conduct of live-line working in power grids.

[0033] like Figure 1 As shown in Figure 3, the preventive testing fixture for the linear tower head clamp used in live-line work includes a U-shaped plate 1 and a base. One end of the U-shaped plate 1 can be connected to the fixed end of a tensile load testing machine. The U-shaped opening size of the U-shaped plate 1 is the same as the width of the linear tower head clamp specimen. The other end of the U-shaped plate 1 is detachably fitted with a base. The base includes two types: a conventional base 2 and a boss base 3. The conventional base 2 is used for preventive testing of the linear tower head clamp specimen, while the boss base 3 is used for preventive testing of single-lead screw specimens.

[0034] like Figure 2 As shown, the conventional base 2 is installed within the opening of the U-shaped plate 1. The conventional base 2 has connecting ends 6 on both sides to mate with the U-shaped plate 1. The conventional base 2 is connected to the pin 7 of the U-shaped plate 1 via the connecting ends 6 on both sides. The conventional base 2 has an opening slot 8, which allows the lead screw of the linear tower head clamping specimen to pass through. Figure 4 As shown, one side of the conventional base 2 can contact the linear tower head card specimen, and the contact surface 9 is a plane. The contact surface 9 between the conventional base 2 and the linear tower head card specimen is a plane to simulate the stress state of the linear tower head card specimen on the crossarm.

[0035] like Figure 3 As shown, the boss base 3 is installed inside the opening of the U-shaped plate 1. The boss base 3 has connecting ends 6 on both sides that mate with the U-shaped plate 1, and the boss base 3 is connected to the pin 7 of the U-shaped plate 1 through the connecting ends 6 on both sides. The boss base 3 has an opening slot 8, which allows the single-lead screw specimen to pass through. Symmetrically, one side of the boss base 3 has a rectangular block boss 10 that mates with the single-lead screw specimen, which simulates the stress state of the single-lead screw specimen on the angle steel of the steel tower.

[0036] The U-shaped plate 1, the standard base 2, and the boss base 3 are all made of Q345 material, enabling this live-line working linear tower head clamp preventive test connection fixture to withstand mechanical load tests with rated loads of 3 tons, 5 tons, and 8 tons. Considering the ease of installation and disassembly of one end of the U-shaped plate 1 to the fixed end of the tensile load testing machine, such as... Figure 1 , Figure 3 , Figure 4 and Figure 5 As shown, one end of the U-shaped plate 1 is provided with a connecting hole 4. Two U-shaped shackles 5 are installed in sequence through the connecting hole 4. The U-shaped plate 1 is connected to the fixed end of the tensile load testing machine through the U-shaped shackles 5.

[0037] Furthermore, as a preferred technical solution in this embodiment, considering the safety during the preventative testing process, to prevent the straight tower head clamp specimen and the single lead screw specimen from sliding out of the opening slot 8, therefore, as Figure 1 , Figure 2 and Figure 3 As shown, in this embodiment, locking pins 11 are provided in the opening slots 8 of both the conventional base 2 and the boss base 3.

[0038] The process of conducting a preventive test on the straight-line tower head clamp using the preventive test connection tooling for live-line working is as follows: Figure 4 As shown:

[0039] Step 1: First, connect one end of the U-shaped plate 1 to the fixed end 15 of the tensile load testing machine through two U-shaped shackles 5, and install the conventional base 2 at the other end of the U-shaped plate 1. After the conventional base 2 is connected to the pin 7 of the U-shaped plate 1 through the connecting ends 6 on both sides, the straight tower head clamp specimen 12 can be installed.

[0040] Step 2, when installing the linear tower head clamp test piece 12, insert the linear tower head clamp test piece 12 into the U-shaped opening of the U-shaped plate 1, while the lead screw 13 of the linear tower head clamp test piece is located in the opening groove 8 of the conventional base 2; since the U-shaped opening size of the U-shaped plate 1 is compatible with the width size of the linear tower head clamp test piece 12, the linear tower head clamp test piece 12 can be inserted into the U-shaped opening of the U-shaped plate 1 and slide within the U-shaped opening.

[0041] Step 3: Lock the opening slot 8 of the conventional base 2 with locking pin 11, and connect the end of the screw 13 of the straight tower head clamping specimen to the force application end 16 of the tensile load testing machine through a single parallel hanging plate 14 and a U-shaped shackle 5.

[0042] Step 4: Apply load using a tensile load testing machine. At this time, the straight tower head clamp specimen 12 contacts one side end face, i.e., the contact surface 9, of the conventional base 2, thus truly simulating the load-bearing capacity of the straight tower head clamp specimen 12 when the force support point is on the crossarm in actual use.

[0043] The process of conducting a preventive test on a single lead screw using the preventive test connection tooling for the straight-line tower head clamp used in live-line work is as follows: Figure 5 As shown:

[0044] Step 1: First, connect one end of the U-shaped plate 1 to the fixed end 15 of the tensile load testing machine through two U-shaped shackles 5, and install the boss base 3 at the other end of the U-shaped plate 1. After the boss base 3 is connected to the pin 7 of the U-shaped plate 1 through the connecting ends 6 on both sides, the single lead screw specimen 18 can be installed.

[0045] Step 2, when installing the single lead screw specimen 18, the rectangular block 17 of the single lead screw specimen is installed on the two bosses 10 on one side of the boss base 3, while the single lead screw specimen 18 is located in the opening slot 8 of the boss base 3.

[0046] Step 3: Lock the opening slot 8 of the conventional base 2 with locking pin 11, and connect the single lead screw specimen 18 to the force application end 16 of the tensile load testing machine through single parallel hanging plate 14 and U-shaped shackle 5.

[0047] Step 4: Apply load using a tensile load testing machine. The rectangular block 17 of the single-lead screw specimen forms a fulcrum through the boss 10, thereby realistically simulating the load-bearing capacity of the single-lead screw specimen 18 when the force support point is on the angle steel of the steel tower in actual use.

[0048] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A preventive testing connection fixture for live-line working tools in power grids, characterized in that: This preventive testing connection fixture for live-line working straight tower head clamps includes a U-shaped plate and a base. One end of the U-shaped plate can be connected to the fixed end of a tensile load testing machine. The U-shaped opening size of the U-shaped plate is the same as the width of the straight tower head clamp specimen. The other end of the U-shaped plate is detachably fitted with a base. The base includes a conventional base and a boss base. The contact surface between the conventional base and the straight tower head clamp specimen is a plane, which can simulate the stress state of the straight tower head clamp specimen on the crossarm. The boss base has a boss on the contact surface with the rectangular block of the single-lead screw specimen, which can simulate the stress state of the single-lead screw specimen on the angle steel of the steel tower. One end of the U-shaped plate is provided with a connecting hole, through which two U-shaped shackles are installed in sequence. The U-shaped plate is connected to the fixed end of the tensile load testing machine through the U-shaped shackles. The conventional base is installed in the opening of the U-shaped plate, and has connecting ends on both sides to cooperate with the U-shaped plate. The conventional base is connected to the U-shaped plate pin through the connecting ends on both sides. The conventional base has an opening groove, and one side of the conventional base can contact the straight tower head clamp specimen, and the contact surface is a plane. The boss base is installed in the opening of the U-shaped plate, and has connecting ends on both sides to cooperate with the U-shaped plate. The boss base is connected to the pin shaft of the U-shaped plate through the connecting ends on both sides. The boss base has an opening groove, and a boss of a rectangular block to cooperate with a single lead screw specimen is symmetrically provided on one side of the boss base. Both the conventional base and the boss base have locking pins in their opening slots.

2. A preventive testing method for a straight-line tower head clamp, the preventive testing method for the straight-line tower head clamp is based on the preventive testing connection fixture for live-line working tools of claim 1, characterized in that, Includes the following steps: Step 1: Connect one end of the U-shaped plate to the fixed end of the tensile load testing machine using two U-shaped shackles, and install a conventional base on the other end of the U-shaped plate; Step 2: Insert the linear tower head clamp specimen into the U-shaped opening of the U-shaped plate, while ensuring that the lead screw of the linear tower head clamp specimen is located in the opening groove of the conventional base. Step 3: Lock the opening slot of the conventional base with a locking pin, and connect the screw end of the straight tower head specimen to the force application end of the tensile load testing machine through a single parallel hanging plate and a U-shaped shackle. Step 4: Apply load using a tensile load testing machine. At this time, the straight tower head clamp contacts one end face of the conventional base, simulating the load-bearing capacity of the straight tower head clamp specimen when the force support point is on the crossarm in actual use.

3. A preventive testing method for a single-lead screw, the preventive testing method for a single-lead screw being based on the preventive testing connection fixture for live-line working tools of claim 1, characterized in that, Includes the following steps: Step 1: Connect one end of the U-shaped plate to the fixed end of the tensile load testing machine through two U-shaped shackles, and install the boss base on the other end of the U-shaped plate; Step 2: Install the rectangular block of the single lead screw specimen on the two bosses on one side of the boss base, while ensuring that the single lead screw specimen is located in the opening slot of the boss base. Step 3: Lock the opening slot of the boss base with the locking pin, and connect it to the force application end of the tensile load testing machine at the end of the single screw rod specimen through a single parallel hanging plate and a U-shaped shackle. Step 4: Apply load using a tensile load testing machine to simulate the load-bearing capacity of a single-lead screw specimen when the stress support point is on the angle steel of a steel tower in actual use.

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