Symmetric balanced type, featuring high rotating speed and integrated skid-mounted design. The frame and crosshead guide adopt an integral structure. The crankshaft has no oil holes and is equipped with an integral connecting flange for rigid direct coupling. Bolts for crankshaft and connecting rod joints are hydraulically tightened. The crosshead is fitted with removable slippers with adjusting shims. The piston rod is connected to the crosshead by means of hydraulic tightening tools.