Brass cable gland manufacturer shares the key points of cable joints in construction
In the installation of power engineering, the cable terminal head and the intermediate joint are important power equipment components in the power transmission and transformation cable line. The manufacturer of the brass cable gland tells you that its function is to disperse the electric field at the cut-off point of the outer shield of the cable terminal head. Protect the cable from being broken down, and also have the functions of internal and external insulation and waterproofing. In cable lines, more than 60% of accidents are caused by accessories, so the quality of connector accessories plays a very important role in the safety and reliability of the entire power transmission and transformation.
Conductor connection requires low resistance and sufficient mechanical strength, and no sharp corners can appear at the connection. Brass cable gland manufacturer reminds you that crimping is commonly used to connect medium and low-voltage cable conductors, and attention should be paid to crimping:
(1) Select a conductor connecting pipe with appropriate conductivity and mechanical strength.
(2) The matching gap between the inner diameter of the crimping tube and the outer diameter of the connected core is 0.8-1.4mm.
(3) The resistance value of the joint after crimping should not be greater than 1.2 times that of the equal-section conductor, and the tensile strength of the copper conductor joint should not be lower than 60N/mm2.
(4) Before crimping, the outer surface of the conductor and the inner surface of the connecting pipe are coated with conductive glue, and the oxide film is destroyed with a wire brush.
(5) Use a file or sandpaper to smooth the sharp corners and burrs on the connecting pipe and core conductor.
Inner semiconductor shielding treatment Where the cable body has an inner shielding layer, the inner shielding layer of the joint of the conductor part of the crimping tube must be restored when making the joint. They can communicate with each other to ensure the continuity of the inner semiconductor so that the field strength at the junction is evenly distributed.
Treatment of the outer semiconductor shield is a semi-conductive material that acts as a uniform electric field on the outside of the cable and connector insulation. Like the inner semiconductor shield, it plays a very important role in the cable and connector. The outer semiconductor port must be neat and uniform, and it also requires a smooth transition with the insulation, and the semiconductor tape is added to the joint to connect with the outer semiconductor shield of the cable body.
Treatment of cable reaction cones During construction, the shape and size of the reaction cones are accurate and the potential distribution on the entire cone surface is equal. When making cross-linked cable reaction cones, special cutting tools are generally used, and micro-flame can also be used. Slightly heat, and cut with a sharp knife, after the basic shape, then use 2mm thick glass to repair and scrape, and finally use sandpaper to polish from coarse to fine until it is smooth.
Metal shielding and grounding treatment The role of metal shielding in cables and connectors is mainly to conduct cable fault short-circuit currents and shield electromagnetic fields from electromagnetic interference to adjacent communication equipment. In operating conditions, metal shielding is at zero potential under good grounding conditions. After the cable fails, it has the ability to conduct short-circuit current in a very short time. The grounding wire should be reliably welded, the metal shield and armored tape on the cable body at both ends should be firmly welded, and the grounding of the terminal head should be reliable.
Sealing and mechanical protection of joints The sealing and mechanical protection of joints are the guarantees to ensure the safe and reliable operation of joints. Manufacturers of brass cable gland suggest that water and moisture should be prevented from penetrating into the joints. In addition, joint protection grooves should be built or cement protection boxes should be installed at the joint position.
Brass cable gland manufacturers share the key points of cable joints in construction. If you want to know more information, you can continue to pay attention to our website.