High-voltage cable air tightness testing device

Abstract

The utility model discloses a high-voltage cable air tightness testing device, which comprises a body, the body is used for testing the air tightness of a corrugated aluminum sleeve (1.1) on the outer layer of a cable (1), two ends of the cable (1) are respectively provided with a sealing cap (2), and the two sealing caps (2) are respectively sleeved at two ends of the cable (1) and are in sealing connection with the corrugated aluminum sleeve (1.1). One sealing cap (2) is a gas inlet sealing cap (2.1) used for being connected with a nitrogen pump (3), and the other sealing cap (2) is a detection sealing cap (2.2) used for being connected with a gas pressure meter (4). The utility model provides a high-voltage cable air tightness testing device which can accurately test the welding quality of a corrugated aluminum sleeve and is simple to operate.

Description

TECHNICAL FIELD

[0001] The utility model relates to test device field, specifically is high voltage cable air tightness test device. BACKGROUND

[0002] High voltage cable is usually used for transmitting high voltage power, in order to ensure the safety and efficiency of power transmission, its manufacturing process requirement is very strict. Wrinkle aluminum cover (also called corrugated aluminum sheath) is a protective layer in high voltage cable, it can help to improve the mechanical strength of cable, and can provide better flexibility and pressure resistance when direct buried or pipeline laying.

[0003] The production process of wrinkle aluminum cover is currently installed in the mode of argon arc welding after longitudinal wrapping of aluminum strip, and the quality of welding is particularly critical, after welding, the weld needs to be strictly checked to ensure the safety of high voltage cable. But in the traditional test process, the form of end cap is mainly used to seal the two ends of semi-finished cable, the end cap is made of heat shrink material, and the principle of heating shrinkage is used to make the end cap fit with the wrinkle aluminum cover, but the end cap cannot withstand high air pressure, and there are obvious disadvantages in the sealing test process. Some clamp type air tightness test devices, such as a high voltage cable argon arc welding metal sheath air tightness test device with the announcement number CN221037836U, but its operation is complicated, the argon arc welding wrinkle is smooth and uneven, and there will be looseness, which is easy to cause air leakage. SUMMARY

[0004] The utility model solves the technical problem that: provide a kind of high voltage cable air tightness test device for the welding quality of wrinkle aluminum cover is accurately tested and the operation is simple.

[0005] The utility model solves the technical scheme that the above problems are adopted: a kind of high voltage cable air tightness test device, including body, the body is used to test the air tightness of cable outer wrinkle aluminum cover, the two ends of the cable are respectively installed one sealing cap, two the sealing cap is respectively connected in the two ends of cable and is sealed with wrinkle aluminum cover Connection, one sealing cap is gas inlet sealing cap for being connected with nitrogen pump, another sealing cap is detection sealing cap for being connected with barometer.

[0006] Compared with the prior art, the utility model discloses the advantage lies in: when the air tightness of the corrugated aluminium sleeve is tested, two sealing caps are directly used to seal two ends of the corrugated aluminium sleeve, the second sealing cap is connected with the nitrogen pump, nitrogen is input into the semi -finished product cable, the other sealing cap is connected with the barometer, and the nitrogen pressure is tested, when the nitrogen pressure in the semi -finished product cable rises to 0.4±0.05mpa, stop filling nitrogen, and the pressure is kept for 2h, if the nitrogen pressure does not reduce, then the corrugated aluminium sleeve weld quality is qualified, otherwise, it is unqualified, wherein the sealing connection of the sealing cap and the cable two ends is used to guarantee the closedness between the sealing cap and the cable, can bear high gas pressure, avoids the air leakage, and the operation is simple in the air tightness testing process, effectively improves the test efficiency and test accuracy.

[0007] As an improvement of the utility model, the two sealing caps and the corrugated aluminium sleeve are connected by circumferential welding, which is more suitable for circumferential welding sealing connection.

[0008] As an improvement of the utility model, the two sealing caps are made of aluminum, and the corrugated aluminium sleeve and the sealing cap are made of aluminum material, which is easier to control during welding, thereby reducing the welding difficulty and improving the test efficiency.

[0009] As an improvement of the utility model, the two ends of the cable are flush, the inner layer of the corrugated aluminium sleeve is provided with a buffer belt, an insulating layer and a conductor from outside to inside, the conductor end face is sealed by glue, and the edge of the glue seal is arranged on the insulating layer, which seals the exposed part of the conductor with glue, prevents nitrogen from flowing through the area where the conductor is located, and allows nitrogen to flow only between the corrugated aluminium sleeve and the insulating layer, thereby reducing the inflation time, and the flush setting of the two ends of the cable helps to ensure the glue sealing quality of the end face of the conductor.

[0010] As an improvement of the utility model, the end face of the cable and the wave crest of the corrugated aluminium sleeve are arranged on the same plane, and the nitrogen is more easily infiltrated between the corrugated aluminium sleeve and the buffer belt along the reduced diameter curved surface of the wave crest when the nitrogen is filled.

[0011] As a kind of improvement of the utility model, the structure of two sealing caps is same, the axis of sealing cap is equipped with a threaded hole for being sealed with barometer, threaded hole on the air inlet sealing cap is connected with a conversion joint, one end of conversion joint is sealed with threaded hole, the other end of conversion joint is sealed with fixed connection, by the improvement, the same structure of sealing cap can reduce the type and quantity of the mold for manufacturing sealing cap, reduce the manufacturing cost of sealing cap, and through the design of conversion joint, the connection sealing problem between valve core and sealing cap can be solved under the condition of sealing cap and barometer thread matching, and conversion joint can be recycled.

[0012] As a kind of improvement of the utility model, the valve core and conversion joint are sealed with fixed connection, the middle section of valve core is equipped with extrusion flange, gasket and sealing washer are arranged between extrusion flange and conversion joint, by the improvement, the valve core and conversion joint are sealed with fixed connection, which can guarantee the firmness of sealing connection between valve core and conversion joint, and during the process of thread connection and fixation between valve core and conversion joint, extrusion flange extrudes gasket and sealing washer, which can not only strengthen the sealing property between valve core and conversion joint, but also strengthen the self-locking firmness of valve core and conversion joint by the elasticity of sealing washer.

[0013] As a kind of improvement of the utility model, the diameter of gasket is larger than that of sealing washer, and the outer ring of gasket is equipped with diameter reducing ring which is bent to the direction of sealing washer, by the improvement, when gasket extrudes sealing washer, sealing washer is close to the axis direction, so as to better guarantee the sealing effect of sealing washer.

[0014] As a kind of improvement of the utility model, the bending thickness of diameter reducing ring is not more than 1 / 3 of the thickness of sealing washer, by the improvement, diameter reducing ring is avoided from directly abutting against the end face of conversion joint during extrusion process. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is the overall sectional view structure schematic diagram of the utility model.

[0016] Figure 2 It is the air inlet sealing cap connection sectional view structure schematic diagram of the utility model.

[0017] Figure 3 It is the valve core connection sectional view structure schematic diagram of the utility model.

[0018] The following components are shown in the diagram: 1. Cable, 1.1. Corrugated aluminum sheath, 1.2. Buffer strip, 1.3. Conductor, 1.4. Insulation layer, 2. Sealing cap, 2.1. Inlet sealing cap, 2.2. Detection sealing cap, 3. Nitrogen pump, 4. Pressure gauge, 5. Adapter, 6. Valve core, 6.1. Extrusion flange, 7. Gasket, 7.1. Reduction ring, 8. Sealing gasket, 9. Adhesive seal, 10. Welding point. Detailed Implementation

[0019] The embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0020] like Figure 1 As shown, a high-voltage cable air tightness testing device includes a main body for testing the air tightness of the outer corrugated aluminum sheath 1.1 of a cable 1. A sealing cap 2 is installed at each end of the cable 1. The two sealing caps 2 are respectively fitted onto the ends of the cable 1 and sealed to the corrugated aluminum sheath 1.1. Both sealing caps 2 and the corrugated aluminum sheath 1.1 are circumferentially welded together. The welding point 10 between the sealing cap 2 and the corrugated aluminum sheath 1.1 is selected at a crest of the corrugated aluminum sheath 1.1. Both sealing caps 2 are made of aluminum. One sealing cap 2 is an air inlet sealing cap 2.1 for connection to a nitrogen pump 3, and the other sealing cap 2 is a detection sealing cap 2.2 for connection to a pressure gauge 4.

[0021] like Figures 1-2 As shown, the two end faces of the cable 1 are flush. The inner layer of the corrugated aluminum sheath 1.1 consists of a buffer strip 1.2, an insulation layer 1.4, and a conductor 1.3 arranged sequentially from the outside to the inside. The end face of the conductor 1.3 is sealed with adhesive 9, and the edge of the adhesive seal 9 is located on the insulation layer 1.4. Nitrogen gas can easily penetrate into the area where the conductor 1.3 is located on the cable 1, so the conductor 1.3 is sealed with adhesive 9 in all directions. The insulation layer 1.4 is extruded and does not easily form gaps. To ensure the sufficient sealing of the conductor 1.3 by the adhesive seal 9, the edge of the adhesive seal 9 is located on the insulation layer 1.4. The corrugated aluminum sheath 1.1 and the insulation layer 1.4 form a channel for nitrogen gas flow. The end face of the cable 1 and the crest of the corrugated aluminum sheath 1.1 are on the same plane.

[0022] like Figures 1-3As shown, the two sealing caps 2 are of the same structure, and a threaded hole for sealing connection with the air pressure gauge 4 is arranged on the axis of the sealing cap 2, the threaded hole is arranged in an inner threaded sleeve, and the inner threaded sleeve is welded on the main body of the sealing cap 2, a conversion joint 5 is connected on the threaded hole of the air inlet sealing cap 2.1, one end of the conversion joint 5 is sealingly connected with the threaded hole, and the other end of the conversion joint 5 is sealingly and fixedly connected with a valve core 6, the valve core 6 is sealingly and fixedly connected with the conversion joint 5 in a threaded manner, a middle section of the valve core 6 is provided with an extrusion flange 6.1, a gasket 7 and a sealing washer 8 are arranged between the extrusion flange 6.1 and the conversion joint 5, the diameter of the gasket 7 is larger than that of the sealing washer 8, and an outer ring of the gasket 7 is provided with a reduced diameter ring 7.1 which is bent towards the sealing washer 8, and the bending thickness of the reduced diameter ring 7.1 is not greater than 1 / 3 of the thickness of the sealing washer 8.

[0023] The valve core 6 is of a conventional structure.

[0024] After the body is installed on the cable 1, the testing steps are as follows: nitrogen is input into the semi-finished cable 1 from the air inlet sealing cap 2.1, and the change of the nitrogen pressure is observed from the air pressure gauge 4 arranged at the detection sealing cap 2.2, when the nitrogen pressure in the semi-finished cable 1 is increased to 0.4±0.05mpa, the nitrogen input is stopped, and the pressure is maintained for 2h, if the nitrogen pressure is not reduced, it is indicated that the welding quality of the corrugated aluminum sleeve 1.1 is qualified, otherwise it is not qualified. If the length of the cable 1 is relatively long, nitrogen can also be input from the detection sealing cap 2.2 to shorten the time length of the air charging and improve the testing efficiency.

[0025] The above only describes the best embodiment of the utility model, but cannot be understood as the limitation of the claims. The utility model is not limited to the above embodiment, and the specific structure can be changed. Any change within the protection scope of the independent claim of the utility model is within the protection scope of the utility model.

Claims

1. A high voltage cable air tightness testing apparatus comprising a body, characterised in that: The body is used for testing the air tightness of the outer layer corrugated aluminum sleeve (1.1) of the cable (1), both ends of the cable (1) are respectively provided with a sealing cap (2), both sealing caps (2) are sleeved on both ends of the cable (1) and are in sealing connection with the corrugated aluminum sleeve (1.1), one sealing cap (2) is an air inlet sealing cap (2.1) used for connecting with a nitrogen pump (3), and the other sealing cap (2) is a detection sealing cap (2.2) used for connecting with a pressure gauge (4).

2. The high voltage cable air tightness testing device of claim 1, wherein: Both sealing caps (2) are in circumferential welding sealing connection with the corrugated aluminum sleeve (1.1).

3. The apparatus of claim 2, wherein: Both sealing caps (2) are made of aluminum.

4. The apparatus of claim 1, wherein: The end faces of both ends of the cable (1) are flush, the inner layer of the corrugated aluminum sleeve (1.1) is sequentially provided with a buffer belt (1.2), an insulation layer (1.4) and a conductor (1.3) from outside to inside, the end face of the conductor (1.3) is provided with a glue seal (9), and the edge of the glue seal (9) is arranged on the insulation layer (1.4).

5. The apparatus of claim 4, wherein: The end face of the cable (1) and the wave crest of the corrugated aluminum sleeve (1.1) are arranged on the same plane.

6. The apparatus of claim 1, wherein: Both sealing caps (2) are the same in structure, the sealing cap (2) is provided with a threaded hole in the axis for sealing connection with the pressure gauge (4), a conversion connector (5) is connected to the threaded hole of the air inlet sealing cap (2.1), one end of the conversion connector (5) is in sealing connection with the threaded hole, and the other end of the conversion connector (5) is in sealing fixed connection with a valve core (6).

7. The apparatus of claim 6, wherein: The valve core (6) and the conversion connector (5) are in threaded sealing fixed connection, the valve core (6) is provided with an extrusion flange (6.1) in the middle section, and the extrusion flange (6.1) is provided with a gasket (7) and a sealing washer (8) between the conversion connector (5).

8. The apparatus of claim 7, wherein: The diameter of the gasket (7) is greater than that of the sealing washer (8), and the outer ring of the gasket (7) is provided with a reduced diameter ring (7.1) bent towards the sealing washer (8).

9. The apparatus of claim 8, wherein: The bending thickness of the reduced diameter ring (7.1) is not greater than 1 / 3 of the thickness of the sealing washer (8).

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