Design of Energy-efficient and Energy-efficient Slag Discharge Device for Large-bore Drilling Rigs

Abstract

Micro pile hole is a kind of bored pile with a diameter of 100~400mm, which has been widely used in the field of transmission line engineering in recent years, and its hole formation usually uses DTH (Down-the-Hole) drilling rig. When DTH drilling rigs operate, the slag discharge method is to use the compressed air provided by the air compressor to blow the muck directly from the bottom of the hole to the ground. However, during the slag discharge process, it is difficult to blow out the muck due to the large cross-sectional area of the annular space between the hole wall and the drill pipe, especially after a certain drilling depth, and it is even more difficult to discharge if wet soil is encountered. Therefore, there is an urgent need to develop a machine for auxiliary slag discharge to improve the efficiency of slag discharge and reduce working energy consumption. In this paper, a barrel slag discharge device connected to the end of the drill pipe and following the drill bit to the bottom of the hole is designed, which can collect and store the rock slag that is difficult to discharge directly outside the hole, achieve a good slag discharge effect, and can reduce the energy consumption of the air compressor and reduce the drilling cost. Through the Fujian UHVDC transmission line project, the reliability and practicability of the barrel slag discharge device are verified.