The Single Jackscrew Chain Clamp reforms the mating side of the weld gap only, and is capable of reforming up to Schedule 40 pipe. The jackscrews of the jackbar exert pressure on the high points of the mating pipe eliminating “Hi-Lo” as pipe and fittings are aligned. Pipe wall thickness to Schedule 80 can be aligned with the Single Jackscrew Chain Clamp. The level and support device of the chain clamp allows the pipe, elbow, tee, flange and other fittings to be held safely and securely in place during the alignment and welding process. For stainless steel or specialty alloy applications, replace the chain of the standard chain clamp with stainless steel chain.