As the name suggests, the “retraction joint†means that the compensation busbar is subjected to heat and cold expansion and contraction, which plays a regulating role and avoids stress on the equipment joint.
The telescopic section is divided into the expansion and contraction of the busbar and the equipment, the expansion and contraction of the busbar and the busbar, and the selection according to the material of the joint. For example, the busbar is made of aluminum, the joint of the equipment is copper, and the aluminum-copper expansion joint and the busbar are used. Aluminum-aluminum expansion joints are used for aluminum, and copper-copper expansion joints are used for copper busbars.
Aluminum and copper should not be directly lapped. In fact, there is no need to use the copper busbar joint part for hot tinning. That is, there is a layer of excessive metal "tin" which is not easily corroded between copper and aluminum to prevent copper. Electrochemical process with aluminum.