Apparatus and method for enhancing fatigue properties of subterranean well drill pipe immediate the area of securement to a tool joint

摘要

An apparatus and method are provided for enhancing fatigue properties of subterranean well drill pipe immediate the area of securement to a tool joint by providing a multi-ramp upset series on the drill pipe which, in effect, enhances fatigue resistance properties of the pipe by increasing the wall thickness on the end of the drill pipe conduit to a greater length than that found on prior art, conventional upsets adjacent the drill pipe. The increased length of this upset configuration provides a smoother transition from the thick upset adjacent the tool joint down to the thin drill pipe body.