A screw nut propulsion mechanism is installed in the frame of the handcar series designed and produced by our company, which can easily move the handcar and prevent damage to the propulsion structure due to incorrect operation. Suitable for KYN61-40.5 armored movable closed metal switching equipment used in three-phase AC 50HZ, 40.5KV single busbar segment power system, handcar is equipped with different primary components, which can be respectively equipped with busbar connection, electric energy measurement, power equipment overload or short circuit protection, and as a protective functional unit during system maintenance. The products meet the relevant provisions of GB/T11022-1999 "General Technical Spare Parts for High voltage Switching Equipment". According to the selection and configuration of the handcart, it can have reliable position and interlock function.