Profile: Xi'an Tiptop Machinery Co. Ltd specializes in manufacturing, distributing, and stocking of oilfield drilling materials. Positive-displacement motors (PDM) make use of a power generation section which is made up of a rotor/stator combination. In order to move a rotor part, a PDM requires hydraulic power from drilling fluid flowing through the power generation part. With a PDM, the stator and rotor work in tandem in the same way that gears do. The stator acts as the outer gear, and is made from a molded elastomer featuring at least two lobes.