The subject matter relates to a clamp for use in disengagably locking together a pair of cylindrical tubular joints of pipe, such as oilfield drill pipe or casing, to convert them into a non-rotatable flat beam. The clamp includes a pair of jaws that are formed to closely conform to the curvature of the outside side surfaces of the two pipe joints. The ends of the jaws extend down past the midlines of the two outer surfaces. The clamp also includes an assembly for holding and moving the jaws together and apart. Once the clamp is positioned over the pair of joints and tightened against their side surfaces they lock the joints together. This locking of the jaws after tightening can be accomplished using a threaded bolt.