Development of Bionic Dual-Connected Drill Pipe for Horizontal Directional Drilling

Abstract

Directional drilling technology is main technical means to control gas and water disasters in coal mines, and drill pipe is an important part of directional drilling tools. However, the broken of the drill pipe is easy to cause the loss of drilling tools and instruments, and even lead to the abandonment of drilling holes. Aiming at the "drilling drop" problem caused by the broken of drill pipe, the animal tendon-bone biological prototype is analyzed, and engineering bionics methods and similar principles are adopted, a dual-connected structure that imitates the form of "tendon-bone" is creatively proposed, which can realize the effect that after the failure of “bone connection pair”, the “tendon connection pair” can still be effectively connected, so that the broken drill tool can be lifted out of the hole. The Φ89 mm bionic dual-connected drill pipe was developed and its mechanical properties were tested. The results show that the tensile strength of the drill pipe can still reach 545kN after fracture, which can realize the goal of pulling the measurement instrument, non-magnetic drilling tool, screw and other drilling tools out of the hole after broken. The research of the thesis can provide a new research idea for solving the problem of "drilling drop" caused by the broken of the drill pipe.