Open End Pipeline Pullback Method in HDD

摘要

This paper presents an open end pipeline pullback method,in which a PE pipe is connected to the special designed pullhead inside the product pipeline.While the pipeline is being pulled in,the drilling mud in the borehole will flow into the PE pipe continuously through the openings in the pullhead.It is an innovative method that does not only solved the problem of buoyancy control of product pipeline during pullback,but also makes same other typical advantages such as borehole pressure control,more secure for pipeline and smaller pulling force.The case study indicates that the method is feasible and cost effective.