The invention belongs to the technical field of power transmission and transformation overhaul devices and particularly relates to a wrench which comprises a first connecting rod and a steering mechanism. A first rotating shaft is rotatably connected into the first connecting rod; one end of the first rotating shaft is provided with a universal joint; the steering mechanism comprises an outer shell, a first bevel gear and a second bevel gear, wherein the first bevel gear and the second bevel gear are arranged in the outer shell; a second rotating shaft is coaxially fixed to the first bevel gear; one end of the second rotating shaft stretches out of the outer shell and then is fixedly connected with the other end of the universal joint; the first bevel gear and the second bevel gear are connected in engaged and transmission modes; a third rotating shaft is coaxially fixedly connected to the second bevel gear; and one end of the third rotating shaft is provided with a sleeve after stretching out of the outer shell. According to the wrench, a traditional universal joint and the steering mechanism are subjected to matching design, the operating radius of the wrench is about 90-135 degrees, and the disassembling and assembling requirements of all bolts in a power transmission and transformation station are met.