摘要 |
<p>A casing/drillpipe protector (P) is disclosed that has a composite structure made up of two separate parts (10, 20). Both parts have cages (32, 36) to secure skeleton functions. The inner part (10) is nested within the outer part (20) such that the open ends of both cages (32, 36) form loops (58, 60, 62, 66, 68, 70, 72) which can be aligned for insertion of a pin (64) to secure the protector (P) to the pipe. The cage of the inner part is smaller but stronger than the cage of the outer part and provides the significant portion of the hoop stress, and therefore radial force of the protector which is used to retain it to the drillpipe.</p> |