Introduction to Electric Cables

The degree of standardization of electric power fittings is very high, so it can also be called power standard parts. The standard parts here are defined in a broad sense. For mechanical parts that meet specific standards, please refer to Baidu Encyclopedia standard parts. Also known as power accessories. Different from the electric equipment, there are scale equipment with complex structure and scale accessories with simple structure.

The factors of cable fittings quality are diverse, in principle, there are the following aspects: 

1. Electrical performance. The quality of electrical performance is the first principle to judge the quality of cable accessories. It mainly considers whether the electric field distribution of cable accessories is reasonable, whether the measures to improve the electric field distribution are appropriate, the electrical strength of materials, dielectric loss and the insulation margin of products, etc. At the same time, the stability of electrical properties, including chemical, physical properties and structural stability of cable accessories, shall be considered, such as whether the performance of stress control materials is stable, whether the stress cone is easy to deform, the influence of cable insulation shrinkage on the electric field distribution of cable accessories and preventive measures, the compatibility of various materials combination, the stability of interface performance, etc. In addition, the thermal performance of cable accessories, such as dielectric loss, contact resistance of conductor connection and its stability, heat conduction and release, and the influence of thermal expansion and contraction on the electrical and mechanical properties of various components, shall also be considered.

2. Sealing performance. The sealing and moisture-proof performance directly affects the electrical performance and service life of cable accessories. Whether the sealing structure of the terminal is reliable and stable. Generally speaking, the intermediate joint shall also have a matching metal moisture-proof shell, especially directly buried or used in humid environment.

3. Mechanical properties. The terminal shall have enough bending resistance and shockproof ability. The intermediate joint shall be able to bear certain tension and measures to prevent external force damage.

4. Process performance. Process performance is an important condition for the design and selection of cable accessories. The installation process shall be as simple as possible, convenient for site construction and short construction period; the requirements for site environment and workers' technical level are not high; the installation quality is easy to control and reliable.

5. Manufacturer's quality assurance system. When prefabricated cable accessories leave the factory, the manufacturer provides rubber prefabricated parts, prefabricated stress cone, porcelain sleeve, shell, impregnant and other parts, which are assembled into integral terminals or joints during field installation. Therefore, the manufacturing quality and installation process of each part are directly related to the final quality of the product.