Dual Pipe for Increased Fluid Flow

Abstract

A dual pipe drill string system having increased fluid flow. The dual pipe system comprises a plurality of pipe sections, each pipe section having an inner rod and an outer pipe. The inner rod and the outer pipe of each pipe section may be coupled to the inner rod and outer pipe of an adjacent pipe section. An annulus between the inner rod and the outer pipe defines a fluid flow path through the dual pipe system. The outer pipe defines a shoulder at each end of an individual pipe section. The inner rod defies at least one stop for maintaining the inner rod within the outer pipe. A spacing assembly disposed around the circumference of the inner rod defines paths for fluid flow and maintains a minimum distance between the stop and the shoulder at one end of outer pipe of the pipe section. An additional spacing assembly disposed around the circumference of the inner rod defines paths for fluid flow and maintains a minimum distance between a second stop on the inner rod and the shoulder at a second end of the outer pipe of the pipe section. Alternatively, the stops on the inner rod may define a feature of the stop defining fluid paths for when the stop contacts the shoulder.

Dependencies are inferred from the claim text.