... beam pumping unit, and the American Petroleum Institute API 11E standard ,the tecnology is mature .1).The ... reduce the stroke frequency for exploitation ,pumping unitType API spec 11ERated suspension center loadReducer TorqueStroke Stroke FrequencyMotor Power ... -48302.81.26,9,124.05.2CYJ3-1.5-4.5HY40-64-60304.51.59,144.55. ... ,12117.0CYJ10-3-37HY320-213-120100373.0,2.5,2.16,9,123018.0CYJ12-4.8-73HF640- ...