Abstract: An apparatus for working pipes has a pair of hinged semicircular rings each having a uniform cross section interior channel. Clamp means permit joining the free ends of the rings to form a hoop clamping onto the outer circumference of a pipe. A continuous slot cut through the outer circumferential surface of each ring communicates with the interior channel therewithin. A wheeled bar rollable circumferentially within the interior channels has a rod extending radially outward through the slot, a tool support mounted on the upper end of the rod permits pipe working tools to be moved orbitably around a pipe.