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Products & Services

Hilong Double-Walled Drill Pipe

Product Introduction 

Double-walled drill pipe is composed of two layers pipes. It is mainly used in reverse circulation drilling technique. The outer drill pipe is the transmission medium of torque and pressure, the space between outer and inner pipes is a channel for pumping circulating medium to well bottom, the inside channel of inner drill pipe returns the circulating medium and rock chips to the outside.

Product Advantage

·No wash out from the walls of a well, reservoir protection, no limit to drill collapse layer and loss formation;
·Less drilling fluid, smaller displacement and faster return speed, the hole is clean;
·Unique advantage in directional well, horizontal well and continuous sampling;
·Suitable for large hole drilling, improving drilling efficiency.New drilling techniques have been developed on the basis of double-walled drill pipe, the most typical representative of it are RDM (Reel Well Drilling Method) and RCCD (Reverse Circulation Centre Discharge).

Product Specification

Size Range (OD of external layer pipe):
Normally 5", 5 1/2", 5 7/8", 6 5/8", 7 5/8", 8 1/2", 9 1/2" and 10".