The axial force gets balanced with the help of balance disc, Concerning lubrication system diluted oil is used for sliding bearing kind of TYPE 85-67、155-67、45-80、85-80、150-100 and grease for rolling bearing kind of all other pumps.

Single Suction Multistage Pump also is a kind of centrifugal pump which consists of the pull rod. The output water pressure of the pump can be very large. These Single Suction Multistage Pump types depend on the rotation of the impeller to obtain the centrifugal force. When the gas density reaches the working range of the mechanical vacuum pump, and it is drawn out. Then gradually obtaining a high vacuum. Multistage pump is by the pump chamber volume changes to achieve suction, compression and exhaust. Therefore, it is a centrifugal pump which can change the cubage.