Abstract:

During the process of horizontal directional drilling（HDD）underground coal mine, the borehole trajectory extension is directly affected by the size and orientation of borehole tilt force that the positive displacement motor (PDM) with curved outer tube transferred to the bit. In this paper, the mathematical model is established through the beam-column method, a two-dimensional stress deformation analysis on the PDM has been carried out, to draw the main factors that affect borehole tilt force. By using programming simulation, the corresponding analysis software is developed. Quantitative parametric sensitivity analysis has been carried out on three main factors, drilling assembly, borehole trajectory and drilling technology, that affected the borehole tilt force, and the size of the influence has been sequenced. The conclusion of this paper can be used as the basis of related parameters selection of directional drilling construction.

Key words: horizontal directional drilling (HDD), positive displacement motor (PDM), borehole tilt force, Mechanical property, parametric sensitivity