... 1.API 11E pumping unit 2.Conventional beam unit 3.energy-efficient, long stroke, small dynamic load,high efficiency,stable Specification of pumping ... industry. We supply oil machines to oilfields for more than 15 years. Our main products include pumping unit, subsuface pump, wellhead ... series walking beam-balanced pumping unit is used to supply the common power in the oil extraction industry. It is ...