The hydraulic fluid viscosity, the volumetric efficiency and the hydraulic system working efficiency drops, divulging increases, even causes the mechanical device to be unable the normal work.

The test method of pressure loss, flow loss and frictional force loss etc. of the hydraulic pumping units is presented, from which the mechanical efficiency and volumetric efficiency are obtained.

The hydraulic agitation and the mechanical agitation are combined in the invention, thereby the efficiency of coagulation and agitation is improved;