目前我们用的北京型钻机,是用钢丝绳加、减压的.在减压钻进中,对井内压力基本上是靠松紧死杀制带来掌握.由于制带新旧程度、清洁状况以及卷筒椭圆度等因素的影响,调压往往不均匀、不准确.因此,经验不足的操作者就较难掌握井下情况.譬如,有时对岩心堵塞、钢粒不足、水量不当等原因造成的效率下降,错误地判断为井下压力不足,就继续放松制带,从而导致井下压力激增,酿成钻杆折断等事故. At present, we use the Beijing-type drilling rig, is the use of wire rope plus decompression. In the decompression drilling, the pressure is basically controlled by the slaughter to bring the master. As the system of new and old, clean status and reel Ovality and other factors, the pressure is often uneven, inaccurate, therefore, less experienced operators are more difficult to grasp the underground situation.For example, sometimes the core plug, lack of steel, water and other reasons caused by the decline in efficiency, Mistakenly judged as inadequate downhole pressure, it will continue to relax the belt, resulting in surge pressure underground, resulting in broken drill pipe and other accidents.