ZA(O) is horizontal, radial split, single stage, single suction, overhung centrifugal pump with volute casing. Centerline mounted; Pump casing,cover and impeller are provided with sealing rings, which are fixed by screws with interference fit.Balance hole and seal ring combined is applied to balance the axial force, to ensure the service life of the bearing. The radial bearings are cylindrical roller bearings, and the thrust bearings are angular contact ball bearings, which can properly bear axial forces from two directions.