The connecting pipe is suitable for the connection between the circular and semi-circular fan-shaped wires and power cables in the power distribution device. The GT series oil blocking type connecting pipe is made of T2 copper rod, and the GT series through-hole type connecting pipe is made of T2 copper pipe punching. Made of GL series oil-blocking type connecting pipe, made of L2 aluminum rod. GTL series copper-aluminum connecting pipes are manufactured by friction welding process with reliable quality.