Key Points of Cable Joints Installation in Power Construction

In the power engineering installation, the cable termination head and the intermediate cable connector are important electrical equipment components in the transmission and transformation cable line. 

Its function is to disperse the electric field at the shielded end of the cable terminal and protect the cable from being broken down. 

It has internal and external insulation and waterproof effects. 

In the cable line, more than 60% of the accidents are caused by the accessories, so the quality of the joint accessories is very important for the safety and reliability of the entire power transmission and transformation.

1 The connecting conductor connection of the conductor requires low resistance and sufficient mechanical strength, and no sharp corners can be formed at the joint.

2 In-semiconductor shielding treatment.

Where the cable body has an inner shielding layer, the inner shielding layer of the joint of the crimping tube conductor portion must be restored when the joint is made, and the inner semiconductor shield of the cable should be left partially to make the connecting head on the connecting tube.

The inner shields are interconnected to ensure the continuity of the inner semiconductor, thereby evenly distributing the field strength at the joint stub.

3 External semiconductor shielding.

The external semiconductor shielding is a semi-conductive material that acts as a uniform electric field on the outside of the cable and cable joint insulation. 

Like the inner semiconductor shielding, it plays an important role in the cable and the joint. 

The outer semiconductor port must be neat and uniform and requires a smooth transition from the insulation, and the cable joint is wound around the semiconductor strip to communicate with the external semiconductor shield of the cable.

4 Cable reaction force cone processing during construction, the shape of the reaction cone is accurate, and the potential distribution is equal on the entire cone surface, in the production of cross-linked cable reaction cones, generally use special cutting tools, can also be used.

The micro-fire is slightly heated, and the cutting is performed with a fast knife. 

After the basic molding, the glass is scraped with 2 mm thick glass and finally sanded from coarse to fine until smooth.

5 Metal shielding and grounding treatment.

Metal shielding in the cable and joints is mainly used to conduct cable fault short-circuit current, and shield electromagnetic field electromagnetic interference to adjacent communication equipment, metal shielding in operation under a good grounding state is zero.

The potential, when a cable fails, has the ability to conduct short-circuit currents in a very short period of time. 

The grounding wire should be soldered reliably. 

The metal shielding and armoring tape on the cable body of the two ends of the box are firmly welded, and the grounding of the terminal head should be reliable.

6 The sealing and mechanical protection of the joint seal and mechanical protection joint is guaranteed to ensure the safe and reliable operation of the cable joint. 

Water and moisture should be prevented from infiltrating into the cable joint. In addition, joint protection grooves or cement protection boxes should be installed at the joint position.