This paper reports the performance of a new type of overrunning clutch that has been developed and installed on sucker rod pumping units. The clutch disengages the power-input shaft of the gear reducer and the unit sheave whenever the torque on the shaft is negative. Based on the results of more than 100 installations, it was found that the pumping speed increased by 9% in average. Liquid production rate increased by up to 30%. Power saving was 23.6% on average. It was also observed that downhole sand and paraffin deposit problems were greatly alleviated. This paper presents pump performance analyses and clutch selection for sucker rod pumping systems.
Copyright 2003, Society of Petroleum Engineers