When setup high voltage cable accessory, please note stress tube and insulation shield cover no less than 20mm, to prevent them break away each other when shrink. Hot shrink accessory may has air gap when it is thermal expansion and cold shrink in run because of its weak elasticity. So seal technology is very import to prevent humidity get in.
Generally, material of high voltage cable accessory is mixture of PE, EVA and EPR. It mainly use stress tube to solve stress concentration problem, also use parameter control to remit electricity stress concentration. Main advantage is portability, easy set, good performance and fair price.
High voltage cable accessory use electric parameter to force the stress in cable insulation shield to evacuate evenly distribution along stress tube. This technology is used in 35kV and below cable accessories. Because stress tube will be heat and can??t work well when it is in high voltage classes.