Water absorption and wet penetration analysis device and analysis method for composite insulator sheath

Abstract

The invention provides a water absorption and moisture penetration analysis device and analysis method for a composite insulator sheath, and belongs to the technical field of electrical equipment detection, and the water absorption and moisture penetration analysis device comprises a sampling mechanism and a water absorption and moisture penetration measurement mechanism. The sampling mechanism comprises a fixing clamp and a cutting assembly, the cutting assembly comprises a power unit and a cutting stamping knife, the cutting stamping knife is coaxially arranged above the composite insulator, the lower end of the cutting stamping knife is provided with an annular blade part, and the outer surface layer of a sheath of the composite insulator is cut down to form a sheath outer pipe body; one axial side of the sheath outer tube body is cut off and then is unfolded to form an experiment sheet body; the water absorption and drenching measurement mechanism comprises an experiment cabin, a moisture permeable cup, a temperature and humidity control module and a quality monitoring module; and the experiment sheet body is sealed at the top of the moisture permeable cup and is arranged in the experiment cabin. According to the water absorption and moisture penetration analysis device for the composite insulator sheath, direct sampling of the composite insulator and accurate measurement of the moisture penetration rate are achieved, and a new thought is provided for follow-up research on the formation process of more water-related faults of the composite insulator.

Description

Technical Field

[0001] The invention belongs to the technical field of power equipment detection, and more specifically, relates to a water absorption and penetration analysis device and an analysis method for a composite insulator sheath. Background Art

[0002] The stability of the power system provides an important guarantee for the development of the national economy. As the link with the largest distance span in the power system, the transmission line is the link between the power generation side and the power consumption side. Its safety is directly linked to the stability of the power supply. As an important component of the transmission line, the importance of insulators is self-evident. Compared with traditional glass insulators and porcelain insulators, composite insulators, as a device with an increasing proportion of use in the domestic insulator field, have the advantages of low cost, short preparation cycle, long service life, light weight, pollution resistance, easy installation and low operation and maintenance costs.

[0003] Composite insulators are made of organic materials such as silicone rubber sheath and glass fiber composite core rod. During operation, they are affected by multiple factors such as high field strength, high humidity and heat, and mechanical load for a long time, resulting in inevitable aging. The surface sheath of the composite insulator ages, the moisture permeability increases, and micropores, discharge, temperature rise and other phenomena are generated. This leads to the hydrolysis of the resin in the core rod, the separation of the matrix and the fiber, and the induction of failures such as brittle fracture, which affects the safe operation of the power grid. However, there is no standard for sampling in the existing silicone rubber moisture permeability research, and the sample extraction cannot be reproduced. Only qualitative research can be carried out. It is impossible to standardize the sampling from the composite insulator that is actually out of the grid and quantitatively analyze the moisture permeability of the silicone rubber sheath. Therefore, quantitatively extracting the silicone rubber sheet in the sheath of the composite insulator and studying its moisture permeability has great theoretical guidance significance and engineering practical value for improving the reliability and stability of the transmission line system. Summary of the invention

[0004] The purpose of the present invention is to provide a water absorption and moisture permeation analysis device for a composite insulator sheath, which solves the problem of irregular sample thickness in the existing composite insulator sheath sampling process, realizes direct sampling of composite insulators and accurate measurement of moisture permeability, and provides new ideas for subsequent research on more water-related fault formation processes of composite insulators.

[0005] To achieve the above object, the technical solution adopted by the present invention is: to provide a composite insulator sheath water absorption and penetration analysis device, comprising: The sampling mechanism includes a fixing fixture and a cutting assembly. The fixing fixture is used to clamp the composite insulator longitudinally. The cutting assembly includes a power unit and a cutting punch. The cutting punch is coaxially arranged above the composite insulator. The lower end of the cutting punch is provided with an annular blade. The power unit is used to drive the cutting punch to move downward to cut off the outer layer of the sheath of the composite insulator to form a sheath outer tube body. The sheath outer tube body is cut off on one side axially and then unfolded to form a test sheet body. The water absorption and penetration measuring mechanism comprises an experimental chamber, a moisture permeability cup, a temperature and humidity control module and a quality monitoring module. The experimental sheet is sealed on the top of the moisture permeability cup and placed in the experimental chamber. The temperature and humidity control module is used to control the temperature and humidity changes in the experimental chamber. The quality monitoring module is used to periodically detect the weight difference of the moisture permeability cup.

[0006] In a possible implementation, the fixing fixture includes: A fixture base, wherein displacement grooves are symmetrically provided on both sides of the upper end surface of the fixture base; A driving screw rod, the middle portion of which passes through the fixture base transversely and is rotatably arranged, and the two ends of the driving screw rod are respectively located in the two displacement grooves and have external threads with opposite rotation directions; Two clamping blocks, the lower ends of the clamping blocks are provided with connecting parts, the lower parts of the two connecting parts are respectively arranged in the two displacement grooves and are respectively threadedly matched with the two ends of the driving screw rod, and the two connecting parts are driven by the driving screw rod to drive the two clamping blocks to approach each other to clamp the composite insulator longitudinally.

[0007] In a possible implementation, clamping bayonet holes are respectively provided at opposite ends of the two clamping blocks, a rotating arm is provided at either end of the driving screw, and a gripping handle is provided at the end of the rotating arm.

[0008] In a possible implementation, the cutting punch is a hollow tube body arranged longitudinally and made of cemented carbide, the inner circumferential wall of the lower part of the hollow tube body has an inclined conical surface, and the inclined conical surface is inclined outward from top to bottom, and the lower end of the inclined conical surface and the lower end of the outer circumferential wall of the hollow tube body form the annular blade portion, and the outer diameter of the annular blade portion is larger than the outer diameter of the core rod of the composite insulator and smaller than the outer diameter of the sheath of the composite insulator.

[0009] In a possible implementation, the water absorption and penetration measurement mechanism further includes: A water injection port, the water injection port being arranged on one side of the experimental cabin; An air vent, the air vent being arranged on the top of the experimental cabin; A control panel, the control panel is used to display the temperature and humidity information in the experimental chamber and the quality information of the moisture permeable cup at all times; Control buttons, which are used to control the temperature and humidity control module and the quality monitoring module respectively; A pressure tray is arranged at the bottom of the experimental chamber and is used to support the moisture permeable cup.

[0010] In a possible implementation, the moisture permeable cup includes: A cup body, wherein an open flange is provided at the upper end of the cup body; A sealing ring, wherein the sealing ring is arranged on the upper end surface of the opening flange, and the test sheet is arranged between the opening flange and the sealing ring; An upper pressure ring, the upper pressure ring being arranged on the upper end surface of the sealing ring; A plurality of connecting pieces, wherein the plurality of connecting pieces circumferentially penetrate and connect the opening flange, the sealing ring, the test sheet body and the upper pressure ring.

[0011] The beneficial effect of the water absorption and moisture permeation analysis device of the composite insulator sheath provided by the present invention is that: compared with the prior art, the composite insulator is clamped longitudinally on the fixed fixture, the power unit drives the cutting punch to move downward, the outer layer of the sheath of the composite insulator is cut off to form the outer tube body of the sheath, and the outer tube body of the sheath is cut on one side of the axial direction and then unfolded to form an experimental sheet. The experimental sheet is sealed on the top of the moisture permeable cup and placed in the experimental cabin, the temperature and humidity control module controls the temperature and humidity changes in the experimental cabin, the quality monitoring module detects the weight difference of the moisture permeable cup in stages, and the water absorption and moisture permeability of the experimental sheet is calculated by the weight difference change of the moisture permeable cup within a specific time, so as to obtain the moisture permeability of the composite insulator. The water absorption and moisture permeability analysis device of the composite insulator sheath provided by the present invention solves the problem of non-standard sample thickness in the existing composite insulator sheath sampling process, realizes direct sampling of the composite insulator and accurate measurement of the moisture permeability, and provides a new idea for subsequent research on more water-related fault formation processes of composite insulators.

[0012] The present invention also provides a method for analyzing water absorption and penetration of a composite insulator sheath, using the device for analyzing water absorption and penetration of a composite insulator sheath, comprising the following steps: S1: Select a composite insulator of a predetermined length, clamp it longitudinally on a fixing fixture, and drive the cutting punch to move downward and cut the composite insulator by a power unit, so as to cut off the outer layer of the sheath of the composite insulator to form an outer tube of the sheath; S2: One side of the outer tube of the sheath is cut along the axial direction and then flattened to form a test sheet, and the test solution is added into the moisture permeable cup. The test sheet is sealed on the top of the moisture permeable cup and placed into the test chamber; S3: Setting the ambient temperature and humidity in the experimental chamber through the temperature and humidity control module, and obtaining the initial mass m0 of the moisture permeable cup through the mass monitoring module; S4: Record the mass m1 of the moisture permeability cup at intervals Δt, obtain the mass variable Δm, and calculate the moisture permeability WVT of the composite insulator sheath, WVT=Δm / (A*Δt), where A is the effective moisture permeability area of ​​the test piece.

[0013] In a possible implementation, in step S1, a composite insulator of a predetermined length is pre-processed, and then longitudinally clamped on a fixing fixture after the pre-processing; The pretreatment method includes punching holes in the core rod of the composite insulator, using anhydrous ethanol to wipe off dirt on the surface of the sheath of the composite insulator and drying it in the shade.

[0014] In a possible implementation, in step S2, the experimental solution is distilled water, acidic, alkaline or neutral salt solution, the experimental sheet is sealed on the top of the moisture permeable cup and then placed in the experimental chamber, the temperature and humidity control module is first started to preheat the moisture permeable cup in the experimental chamber, and the experimental sheet is cut into conformable discs along the outer contour of the moisture permeable cup.

[0015] In a possible implementation, silicone oil, paraffin or beeswax is applied to the outer edge of the conformable disc for sealing.

[0016] The beneficial effect of the water absorption and permeation analysis method of the composite insulator sheath provided by the present invention is that: compared with the prior art, a composite insulator of a predetermined length is selected, and it is clamped longitudinally on a fixing fixture, a power unit drives a cutting punch to move downward and cut the composite insulator, and the outer surface layer of the sheath of the composite insulator is cut off to form an outer tube body of the sheath; one side of the outer tube body of the sheath is cut along the axial direction and then flattened to form an experimental sheet body, an experimental solution is added into a moisture permeability cup, the experimental sheet body is sealed on the top of the moisture permeability cup and placed in an experimental cabin; the ambient temperature and ambient humidity in the experimental cabin are set by a temperature and humidity control module, and the initial mass m0 of the moisture permeability cup is obtained by a quality monitoring module; the mass m1 of the moisture permeability cup is recorded at an interval time Δt, the mass variable Δm is obtained, and the moisture permeability WVT of the composite insulator sheath is calculated, WVT=Δm / (A*Δt), wherein A is the effective moisture permeability area of ​​the experimental sheet body. The present invention provides a method for analyzing water absorption and moisture permeation of a composite insulator sheath, which realizes direct sampling of the composite insulator and accurate measurement of the moisture permeability, and provides a new idea for subsequent research on more water-related fault formation processes of the composite insulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of the structure of the sampling mechanism provided by the present invention; Figure 2 A top view of the sampling mechanism provided by the present invention; Figure 3 A diagram showing the change from the outer tube body of the sheath to the experimental sheet body provided by the present invention; Figure 4 A schematic diagram of the structure of a moisture permeable cup provided by the present invention; Figure 5 A schematic diagram of the structure of the water absorption and penetration measurement mechanism provided by the present invention; Figure 6 The present invention provides a flow chart of a method for analyzing water absorption and penetration of a composite insulator sheath.

[0019] In the figure: 1. Cutting punch; 2. Annular blade; 3. Clamp base; 4. Displacement slot; 5. Driving screw; 6. Clamping block; 7. Clamping bayonet; 8. Rotating arm; 9. Holding handle; 10. Sheath outer tube; 11. Experimental sheet; 12. Experimental cabin; 13. Moisture permeable cup; 14. Water inlet; 15. Ventilation outlet; 16. Control panel; 17. Control button; 18. Pressure tray; 19. Open flange; 20. Sealing ring; 21. Upper pressure ring; 22. Connector. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] Unless explicitly defined otherwise, the use of terms such as "first," "second," or "third," etc., are intended to distinguish different objects rather than to describe a specific order.

[0022] Unless otherwise expressly defined, directional words such as the terms "center", "lateral", "longitudinal", "horizontal", "vertical", "top", "bottom", "inside", "outside", "up", "down", "front", "back", "left", "right", "clockwise", "counterclockwise", "high", "low", etc., indicating directions or positional relationships are based on the directions and positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, so they cannot be understood as limiting the specific scope of protection of the present invention.

[0023] See also Figures 1 to 5 The present invention provides a composite insulator sheath water absorption and penetration analysis device. The composite insulator sheath water absorption and penetration analysis device comprises a sampling mechanism and a water absorption and penetration measurement mechanism.

[0024] The sampling mechanism includes a fixing fixture and a cutting assembly. The fixing fixture is used to clamp the composite insulator longitudinally. The cutting assembly includes a power unit and a cutting punch 1. The cutting punch 1 is coaxially arranged above the composite insulator. The lower end of the cutting punch 1 is provided with an annular blade 2. The power unit is used to drive the cutting punch 1 to move downward to cut off the outer layer of the sheath of the composite insulator to form a sheath outer tube body 10. The sheath outer tube body 10 is cut off on one side axially and then unfolded to form an experimental sheet body 11. The water absorption and permeation measurement mechanism includes an experimental cabin 12, a moisture permeable cup 13, a temperature and humidity control module and a quality monitoring module. The experimental sheet body 11 is sealed on the top of the moisture permeable cup 13 and placed in the experimental cabin 12. The temperature and humidity control module is used to control the temperature and humidity changes in the experimental cabin 12. The quality monitoring module is used to periodically detect the weight difference of the moisture permeable cup 13.

[0025] The present invention provides a composite insulator sheath water absorption and moisture permeation analysis device. Compared with the prior art, the composite insulator is clamped longitudinally on a fixed fixture, and the power unit drives the cutting punch 1 to move downward to cut off the outer layer of the composite insulator sheath to form a sheath outer tube 10. The sheath outer tube 10 is cut on one side of the axial direction and then unfolded to form an experimental sheet 11. The experimental sheet 11 is sealed on the top of a moisture permeable cup 13 and placed in an experimental cabin 12. The temperature and humidity control module controls the temperature and humidity changes in the experimental cabin 12. The quality monitoring module detects the weight difference of the moisture permeable cup 13 in stages. The water absorption and moisture permeability of the experimental sheet 11 is calculated by the weight difference change of the moisture permeable cup 13 within a specific time, and the moisture permeability of the composite insulator can be obtained. The composite insulator sheath water absorption and moisture permeation analysis device provided by the present invention solves the problem of non-standard sample thickness in the existing composite insulator sheath sampling process, realizes direct sampling of composite insulators and accurate measurement of moisture permeability, and provides a new idea for subsequent research on more water-related fault formation processes of composite insulators.

[0026] The power unit uses a press, and the main purpose of the press is to drive the cutting punch 1 to move downward to apply the force required to cut the composite insulator sheath. The press uses a JRI-A four-column two-platen top-type booster, with a cylinder diameter of 63mm and a tonnage of 3T. A fixed fixture is fixed above the pressure platform of the press to clamp the composite insulator to be tested to ensure accurate cutting stroke.

[0027] See also Figure 1 to Figure 2 The fixing fixture includes a fixture base 3, a driving screw 5 and two clamping blocks 6. Displacement grooves 4 are symmetrically provided on both sides of the upper end surface of the fixture base 3, and the two displacement grooves 4 are not connected to each other; the middle part of the driving screw 5 horizontally penetrates the fixture base 3 and can be rotatably arranged, and the two ends of the driving screw 5 are respectively located in the two displacement grooves 4 and have external threads with opposite rotation directions; the lower end of the clamping block 6 has a connecting part, and the connecting part is a block or a column integrally formed on the lower end surface of the clamping block 6. The lower parts of the two connecting parts are respectively arranged in the two displacement grooves 4 and are threadedly matched with the two ends of the driving screw 5. Since the external threads at the two ends of the driving screw 5 have opposite rotation directions, when the driving screw 5 is rotated, the two connecting parts are driven by the driving screw 5 to drive the two clamping blocks 6 to approach each other to clamp the composite insulator longitudinally.

[0028] See also Figure 1 and Figure 2 The opposite ends of the two clamping blocks 6 are respectively provided with clamping bayonet 7, which is a triangular bayonet and can adaptively clamp composite insulators of different outer diameters. A rotating arm 8 is provided at either end of the driving screw 5, and a gripping handle 9 is provided at the end of the rotating arm 8. The gripping handle 9 is used to drive the rotating arm 8 to rotate, thereby driving the driving screw 5 to rotate, so that the two clamping blocks 6 can approach each other and clamp the composite insulator or move away from each other to detach from the composite insulator.

[0029] See also Figures 1 to 3The cutting punch 1 is a hollow tube body arranged longitudinally and made of cemented carbide. The inner peripheral wall of the lower part of the tungsten steel hollow tube body has an inclined conical surface, which is inclined outward from top to bottom. The lower end of the inclined conical surface and the lower end of the outer peripheral wall of the hollow tube body form an annular blade 2. The outer diameter of the annular blade 2 is larger than the outer diameter of the core rod of the composite insulator and smaller than the outer diameter of the sheath of the composite insulator. The cutting punch 1 can be made of tungsten steel. Tungsten steel is a sintered composite material composed of one or more metal carbides with a grain size between 0.2 and 10 microns. The carbide grains and the metal are bonded together by a metal binder. Corresponding to different voltage levels, the cutting punch has different specifications, corresponding to different cutting punches. The outer diameter of the cutting punch under the same voltage level is 4mm smaller than the outer diameter of the composite insulator sheath of the voltage level. The thickness of the annular blade 2 is 1mm, so as to cut out a thin sheet of the sheath outer tube body 10 with a thickness of 2mm. The length of the annular blade 2 is 20 mm, and the total length of the cutting punch 1 is 80 mm, leaving a margin for both ends of the sample to avoid unevenness of the sheath outer tube body 10 sample caused by uneven stress during cutting.

[0030] See also Figure 5 The water absorption and penetration measurement mechanism also includes a water injection port 14, a vent 15, a control panel 16, a control button 17 and a pressure tray 18. The internal dimensions of the experimental chamber 12 are 250mm*260mm*230mm. The water injection port 14 is arranged on one side of the experimental chamber 12. A water tank is arranged inside the water absorption and penetration measurement mechanism, and an external water tank can also be connected to store the injected water. The vent 15 is arranged on the top of the experimental chamber 12, which may assist in adjusting the temperature and humidity in the experimental chamber 12; the main purpose of the temperature and humidity control module is to increase the temperature and humidity of the experimental environment, accelerate the diffusion speed of the water sample, and ensure ventilation in the test environment to prevent the diffused water vapor from being lost and condensing on the inner wall of the equipment to affect the test results. The control button 17 is used to control the temperature and humidity control module and the quality monitoring module respectively; the pressure tray 18 is arranged at the bottom of the experimental chamber 12, and the pressure tray 18 is used to support the moisture permeable cup 13. The main purpose of the quality monitoring module is to monitor and record the quality of the sample and the remaining water sample in the moisture permeable cup 13 in real time. Its core is an electromagnetic force sensor with an accuracy of 0.0001g and a maximum range of 300g. The sensor pressure tray 18 has a diameter of 100mm and can realize full automatic internal calibration. The module contains a storage and calculation unit, which can store, count and print the measurement results. The control panel 16 constantly displays the temperature and humidity information in the experimental cabin 12 and the quality information of the moisture permeable cup 13. The control panel 16 is a 5-inch TFT64K color LCD display set on the front side, which can read data in real time.

[0031] See also Figure 4The permeable cup 13 includes a cup body, a sealing ring 20, an upper pressure ring 21 and a plurality of connectors 22. An open flange 19 is provided at the upper end of the cup body; the sealing ring 20 is provided on the upper end surface of the open flange 19, and the test sheet 11 is provided between the open flange 19 and the sealing ring 20; the upper pressure ring 21 is provided on the upper end surface of the sealing ring 20; a plurality of connectors 22 circumferentially penetrate and connect the open flange 19, the sealing ring 20, the test sheet 11 and the upper pressure ring 21. The main purpose of the permeable cup 13 is to clamp the test sample and hold distilled water, acid, alkali and salt solutions waiting for diffusion water samples. The permeable cup 13 is mainly divided into three layers, namely, the upper pressure ring 21 of the upper layer, the sealing ring 20 of the middle layer and the open flange 19 of the lower layer. The connectors 22 are hexagonal bolts and butterfly nuts that cooperate with each other. Among them, the hexagonal bolts, butterfly nuts, upper layer and lower layer are made of high-quality aluminum alloy. The moisture permeable cup 13 is 37mm high, with a cup wall of 2mm, an inner diameter of 35mm, and a height of 30mm. The middle layer is made of rubber, which can provide stronger gas tightness. The upper layer of the moisture permeable cup 13 is 2.5mm thick, and the middle layer is 2mm thick, and the two are of the same shape.

[0032] Based on the same inventive concept, please refer to Figures 1 to 6 The present invention also provides a composite insulator sheath water absorption and penetration analysis method, using the composite insulator sheath water absorption and penetration analysis device, comprising the following steps: S1: Select a composite insulator of a predetermined length, clamp it longitudinally on a fixing fixture, and drive the cutting punch 1 to move downward and cut the composite insulator by a power unit, so as to cut off the outer layer of the sheath of the composite insulator to form a sheath outer tube 10; S2: One side of the outer tube 10 of the sheath is cut along the axial direction and then flattened to form a test sheet 11, and a test solution is added into the moisture permeable cup 13, and the test sheet 11 is sealed on the top of the moisture permeable cup 13 and placed into the test chamber 12; S3: setting the ambient temperature and humidity in the experimental chamber 12 through the temperature and humidity control module, and obtaining the initial mass m0 of the moisture permeable cup 13 through the mass monitoring module; S4: Record the mass m1 of the moisture permeable cup 13 at intervals Δt, obtain the mass variable Δm, and calculate the moisture permeability WVT of the composite insulator sheath, WVT=Δm / (A*Δt), where A is the effective moisture permeability area of ​​the experimental sheet 11.

[0033] The beneficial effect of the water absorption and permeation analysis method of the composite insulator sheath provided by the present invention is that: compared with the prior art, a composite insulator of a predetermined length is selected, and it is longitudinally clamped on a fixing fixture, a power unit drives a cutting punch 1 to move downward and cut the composite insulator, and the outer layer of the sheath of the composite insulator is cut off to form a sheath outer tube body 10; one side of the sheath outer tube body 10 is cut along the axial direction and flattened to form an experimental sheet 11, an experimental solution is added to a moisture permeable cup 13, and the experimental sheet 11 is sealed on the top of the moisture permeable cup 13 and placed in an experimental chamber 12; the ambient temperature and ambient humidity in the experimental chamber 12 are set by a temperature and humidity control module, and the initial mass m0 of the moisture permeable cup 13 is obtained by a quality monitoring module; the mass m1 of the moisture permeable cup 13 is recorded at an interval time Δt, the mass variable Δm is obtained, and the moisture permeability WVT of the composite insulator sheath is calculated, WVT=Δm / (A*Δt), wherein A is the effective moisture permeability area of ​​the experimental sheet 11. The present invention provides a method for analyzing water absorption and moisture permeation of a composite insulator sheath, which realizes direct sampling of the composite insulator and accurate measurement of the moisture permeability, and provides a new idea for subsequent research on more water-related fault formation processes of the composite insulator.

[0034] In step S1, a composite insulator of a predetermined length is pre-processed, and the predetermined length of the composite insulator is usually 6-7 cm. After the pre-processing, the composite insulator is longitudinally clamped on a fixing fixture.

[0035] The pretreatment method includes punching holes in the core rod of the composite insulator, using anhydrous ethanol to wipe off dirt on the surface of the sheath of the composite insulator and drying it in the shade.

[0036] After the outer tube body 10 of the sheath is cut and flattened to the test sheet body 11, holes are pre-punched on the test sheet body 11, and the holes match the positions of the multiple connectors 22 on the moisture permeable cup 13, so as to facilitate the subsequent sealing installation of the test sheet body 11 on the moisture permeable cup 13. After the holes are punched, the test sheet body 11 is placed in an oven for drying to completely dehydrate it, so as to avoid affecting the subsequent moisture permeability experiment.

[0037] In step S2, the experimental solution is distilled water, acidic, alkaline or neutral salt solution. The experimental sheet 11 is sealed on the top of the breathable cup 13 and then placed on the pressure tray 18 of the experimental chamber 12. The temperature and humidity control module is first started to preheat the breathable cup 13 in the experimental chamber 12 to avoid the defect of bulging on the breathable cup 13 when the experimental sheet 11 is installed early. The experimental sheet 11 is cut into a conformable disc along the outer contour of the breathable cup 13. Silicone oil, paraffin or beeswax is applied to the outer edge of the conformable disc for sealing, and it is avoided to avoid touching to prevent moisture from escaping from other gaps, thereby playing a sealing role.

[0038] Before step S3, first inject a proper amount of distilled water into the water inlet 14, use the control button 17 to set the appropriate ambient temperature and humidity, and the control button 17 controls the ambient temperature and humidity in the experimental chamber 12 through the temperature and humidity control module. After the ambient temperature and humidity are stable, use the pressure tray 18 to weigh and record the initial mass m0 of the moisture permeable cup 13 at this time.

[0039] In the formula WVT=Δm / (A*Δt), Δm=m1−m0, and A is the effective moisture permeability area of ​​the experimental sheet 11 , that is, the area of ​​the experimental sheet 11 inside the sealing ring 20 .

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A composite insulator sheath water absorption and penetration analysis device, characterized in that: include: The sampling mechanism includes a fixing fixture and a cutting assembly. The fixing fixture is used to clamp the composite insulator longitudinally. The cutting assembly includes a power unit and a cutting punch. The cutting punch is coaxially arranged above the composite insulator. The lower end of the cutting punch is provided with an annular blade. The power unit is used to drive the cutting punch to move downward to cut off the outer layer of the sheath of the composite insulator to form a sheath outer tube body. The sheath outer tube body is cut off on one side axially and then unfolded to form a test sheet body. The water absorption and penetration measuring mechanism comprises an experimental chamber, a moisture permeability cup, a temperature and humidity control module and a quality monitoring module. The experimental sheet is sealed on the top of the moisture permeability cup and placed in the experimental chamber. The temperature and humidity control module is used to control the temperature and humidity changes in the experimental chamber. The quality monitoring module is used to periodically detect the weight difference of the moisture permeability cup.

2. The composite insulator sheath water absorption and penetration analysis device according to claim 1, characterized in that: The fixing fixture comprises: A fixture base, wherein displacement grooves are symmetrically provided on both sides of the upper end surface of the fixture base; A driving screw rod, the middle portion of which passes through the fixture base transversely and is rotatably arranged, and the two ends of the driving screw rod are respectively located in the two displacement grooves and have external threads with opposite rotation directions; Two clamping blocks, the lower ends of the clamping blocks are provided with connecting parts, the lower parts of the two connecting parts are respectively arranged in the two displacement grooves and are respectively threadedly matched with the two ends of the driving screw rod, and the two connecting parts are driven by the driving screw rod to drive the two clamping blocks to approach each other to clamp the composite insulator longitudinally.

3. A composite insulator sheath water absorption and penetration analysis device as claimed in claim 2, characterized in that: The opposite ends of the two clamping blocks are respectively provided with clamping bayonet holes, and either end of the driving screw rod is provided with a rotating arm, and the end of the rotating arm is provided with a holding handle.

4. The composite insulator sheath water absorption and penetration analysis device according to claim 1, characterized in that: The cutting punch is a hollow tube body arranged longitudinally and made of hard alloy. The inner circumferential wall of the lower part of the hollow tube body has an inclined conical surface, and the inclined conical surface is inclined outward from top to bottom. The lower end of the inclined conical surface and the lower end of the outer circumferential wall of the hollow tube body form the annular blade portion. The outer diameter of the annular blade portion is larger than the outer diameter of the core rod of the composite insulator and smaller than the outer diameter of the sheath of the composite insulator.

5. The composite insulator sheath water absorption and penetration analysis device according to claim 1, characterized in that: The water absorption and penetration measuring mechanism further comprises: A water injection port, the water injection port being arranged on one side of the experimental cabin; An air vent, the air vent being arranged on the top of the experimental cabin; A control panel, the control panel is used to display the temperature and humidity information in the experimental chamber and the quality information of the moisture permeable cup at all times; Control buttons, which are used to control the temperature and humidity control module and the quality monitoring module respectively; A pressure tray is arranged at the bottom of the experimental chamber and is used to support the moisture permeable cup.

6. The composite insulator sheath water absorption and penetration analysis device according to claim 1, characterized in that: The moisture permeable cup comprises: A cup body, wherein an open flange is provided at the upper end of the cup body; A sealing ring, wherein the sealing ring is arranged on the upper end surface of the opening flange, and the test sheet is arranged between the opening flange and the sealing ring; An upper pressure ring, the upper pressure ring being arranged on the upper end surface of the sealing ring; A plurality of connecting pieces, wherein the plurality of connecting pieces circumferentially penetrate and connect the opening flange, the sealing ring, the test sheet body and the upper pressure ring.

7. A method for analyzing water absorption and penetration of a composite insulator sheath, characterized in that: The water absorption and penetration analysis device for the composite insulator sheath according to any one of claims 1 to 6 comprises the following steps: S1: Select a composite insulator of a predetermined length, clamp it longitudinally on a fixing fixture, and drive the cutting punch to move downward and cut the composite insulator by a power unit, so as to cut off the outer layer of the sheath of the composite insulator to form an outer tube of the sheath; S2: One side of the outer tube of the sheath is cut along the axial direction and then flattened to form a test sheet, and the test solution is added into the moisture permeable cup. The test sheet is sealed on the top of the moisture permeable cup and placed into the test chamber; S3: Setting the ambient temperature and humidity in the experimental chamber through the temperature and humidity control module, and obtaining the initial mass m0 of the moisture permeable cup through the mass monitoring module; S4: Record the mass m1 of the moisture permeability cup at intervals Δt, obtain the mass variable Δm, and calculate the moisture permeability WVT of the composite insulator sheath, WVT=Δm / (A*Δt), where A is the effective moisture permeability area of ​​the test piece.

8. A method for analyzing water absorption and penetration of a composite insulator sheath according to claim 7, characterized in that: In step S1, a composite insulator of a predetermined length is pre-processed, and then longitudinally clamped on a fixing fixture after the pre-processing; The pretreatment method includes punching holes in the core rod of the composite insulator, using anhydrous ethanol to wipe off dirt on the surface of the sheath of the composite insulator and drying it in the shade.

9. A method for analyzing water absorption and penetration of a composite insulator sheath according to claim 7, characterized in that: In step S2, the experimental solution is distilled water, acidic, alkaline or neutral salt solution. The experimental sheet is sealed on the top of the moisture permeable cup and then placed in the experimental chamber. The temperature and humidity control module is first started to preheat the moisture permeable cup in the experimental chamber, and the experimental sheet is cut into free-form discs along the outer contour of the moisture permeable cup.

10. A method for analyzing water absorption and penetration of a composite insulator sheath according to claim 9, characterized in that: Apply silicone oil, paraffin or beeswax to the outer edge of the conformable disc for sealing.

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