Abstract: Tool chatter during a pipe threading operation is reduced by positioning a pipe end to be threaded alongside a threading tool, positioning a radially expandable mandrel inside of the pipe end, securing the mandrel by expansion, threading the pipe end with the threading tool, and removing the mandrel. A preferred mandrel comprises a housing, an elastomeric sleeve, a piston, and a cylinder head. The elastomeric sleeve covers the outside cylindrical surface of the housing. The device is filled with hydraulic fluid and the piston is actuated to expand the sleeve against the inside of the pipe. Vibrations from the cutting operation are absorbed by the hydraulic fluid after being transmitted into it via the elastomeric sleeve.

Abstract: There is provided an elastomeric annular seal having a chamfered first end and a chamfered second end and a generally cylindrical outer surface extending between the first end and the second end. Preferably, the elastomeric annular seal is mounted on a rigid sleeve. The seal has annular cross sections to fit the sleeve and the chamfers are radiused when viewed in longitudinal section so that the radiused chamfered ends of the elastomeric annular seal together with the outside surface of the rigid sleeve form annularly shaped cups. Fluid pressure in the cup will expand the seal against the inside wall of a tubular when the seal/sleeve is appropriately sized for the tubular in which it is deployed.