Iron pipes, tools used to fasten or loosen when fittings.

Chain pipe wrench. It comprises a pliers handle and a chain hinged at one end to the plier handle, the front end of which is provided with teeth that engage with the chain. Further, the chain is hinged with the handle shank through the coupling plate, that is, one end of the chain is hinged with one end of the coupling plate, and the other end of the coupling plate is hinged with the handle. The teeth on the front end of the pliers handle are circularly distributed. When the chain-type pipe wrench is in operation, the non-hinge end of the chain is free and is not fixed or hinged with the pliers handle. The clamping and rotation of the pipe is achieved by the friction between the pipe and the chain that is wound around it. The torsional force is generated by the meshing force between the local cone and the chain at the front end of the pliers handle. The pliers handle has no applied point on the surface of the pipe. Therefore, the chain pipe wrench of the present invention overcomes the shortcomings of the existing chain pipe wrenches, and can not only clamp and rotate the metal pipe fittings but also the ceramic pipe fittings, thin-walled pipe fittings, and plastic pipe fittings. Does not produce bite marks, do not damage the surface of the pipe.