Dual Member Pipe Joint For A Dual Member Drill String

摘要

A dual member drill string having a plurality of dual member drill string sections for use in horizontal directional drilling operations. Each drill string section having an outer member and an inner member that is rotatable independently of the outer member. The outer member has a pin end and a box end. The inner member has a pin end disposed within the pin end of the outer member and a box end disposed within the box end of the outer member.

主权项

1. A drill string section for use in rotary boring applications, the section comprising:
an elongate, hollow outer member having a pin end and a box end, wherein the pin end and the box end are correspondingly formed for torque-transmitting engagement with an adjacent outer member, the outer member having an inner surface forming a shoulder, and an elongate inner member disposed within the outer member and rotatable independently of the outer member, the inner member comprising:
a first pin end disposed within the pin end of the outer member,a corresponding second pin end disposed within the box end of the outer member;a first stop member disposed at the first pin end, the first stop member comprising a substantially planar surface defining a fluid passage between the first stop member and the shoulder of the outer member; anda sleeve member comprising an interior surface corresponding to the first and second pin ends; wherein the sleeve is held in place to the second pin end within the box end of the outer member and proximate a second shoulder formed on the outer member;wherein the first pin end is slidably receivable in connector free torque-transmitting engagement with the sleeve member of an adjacent inner member.