... a rigid lower deviated beam balance . The beam pumping unit endows some features of reliable performance,simple structure,easy ... Petroleum Institute API 11E standard ,the tecnology is mature .1).The overall struture is reasonable,steady work ,small noise ... -2.8HY25-64-30302.80.759,143.24.5CYJ3-1.2-2.8HY25-64-48302.81.26,9,124 ... .05.2CYJ3-1.5-4.5HY40-64-60304.51.59,144.55 ...