Factors influencing the quality of cable accessories
The quality factors of cable accessories are diversified, in principle, there are the following aspects:
The electrical performance is the first principle to judge the quality of cable accessories. The main consideration is 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 insulation margin of products, etc. At the same time, also must consider the stability of performance, including chemical and physical properties of the cable accessories material and structure stability, the stress control material performance is stable, for example, the stress cone is easy to deformation, cable insulation retraction of the distribution of electric field of cable accessories and measures to prevent the influence of compatibility of various materials with combined interface performance stability, etc. In addition, the thermal performance of cable accessories should also be considered, such as dielectric loss, contact resistance of conductor connection and its stability, heat conduction release, thermal expansion and contraction on the electrical and mechanical properties of each component.
The sealing performance
Sealing moisture-proof performance directly affects the electrical performance and service life of cable accessories. Terminal sealing structure is reliable and stable. In general, intermediate joints should also have a matching metal damp proof enclosure, especially for direct burial or use in wet environments.
The terminal should have enough bending and shock resistance. The intermediate joint should be able to withstand a certain tension and prevent external damage measures.
Process performance is an important condition of cable accessories design and selection, installation process should be as simple as possible, convenient for site construction, short period of time; The requirements for the site environment and the technical level of workers are not high; Installation quality easy to control, reliable quality and so on.
Manufacturer's quality assurance system
When the prefabricated cable accessories leave the factory, the manufacturer provides prefabricated rubber parts, prefabricated stress cones, porcelain sleeves, shells, impregnators and other parts, which are assembled into an overall terminal or joint during on-site installation. Therefore, the manufacturing quality and installation process of each part are directly related to the final quality of the product.