Lithium battery Rail impact wrench machine Double lithium traveling cantilever power wrench (model: LDB171X) is composed of host, control system, battery system and rail traveling part. The utility model has the advantages of compact structure, light weight, flexible assembly and disassembly, convenient use and no exhaust emission. It can be transported separately, which is convenient for single person to carry on site. The weight of the separated part is less than 15kg. It is applicable to the laying, maintenance and emergency rescue of railway, and is specialized in various railway bolt operations