RESEARCH AND APPLICATION OF EFFECTIVE STEERING PDM

There is usually a stabilizer on the conventional bent housing positive displacement motor(PDM), and this will lead to the difficulty of putting weight on bit. Then the steering efficiency of BHA in deeper section of a well would be affected, and a spiral hole would be drilled when the double driven drilling teehnology was used, which would influence the quality of well trajectory. In this paper, a new effective steering PDM was developed. Different from the conventional bend PDM, the stabilizer was on the head of drive shaft, thus the stabilizer would be more closed to bit and rotate continuously when the PDM was working, Based on the analysis of strength, the structure of effective steering PDM was optimized. The steering ability of BHA with this PDM was also analyzed. The calculation results showed that the effective steering PDM could improve not only the slide steering ability, but also the rotary steering ability. The application results showed that the weight could be easily put on the bit, and a smooth hole could be drilled with effective steering PDM.