We used to use either air agitators or hung-chain agitators in vessels in our corporation, but the operating cost was very high and agitating quality was not good. So, it is essential to abandon outdated agitators and empolder new mechanical agitators. Taking the agitators used in dissolving vessels and slurry vessels in our corporation for example, this text introduces in detail the study steps of new mechanical agitators: determining install types and blade stages according to the vessel body; pre-selecting the agitator configuration according to material property and agitating purpose; analyzing blade structure and confirming blade dimension; confirming baffle quantity and its dimension; calculating agitating power and rotating speed, confirming agitating shaft diameter and other parameters.