DEVELOPMENT AND APPLICATION OF KELLY BUSHING TORQUE GAUGE

For accurate measurement torque, it does not only provide reference for design of optimum drilling assembly, but also be useful to judge downhole operating mode through processing drill string torque signal. At present, there is a certain progress in the work concerned with the researches of drill string torque measurement at home and abroad, but in the aspect of torque measurement accuracy and reliability, it is still imperfect. Therefore, in this paper, kelly bushing torque gauge that consists of launcher, receiver, measurement transducer has been developed through reconstruct kelly bushing. It can measure directly drill string torque. Lab. test and field application proved that operation of kelly bushing torque gauge was reliable, meanwhile, it solved the torque measurement problem that has been a puzzle in drilling industry for a long time.