1. Why self-balancing pump bearings get hot？

The problem of bearing heating during the development of self-balancing pumps once became a pain point. It was caused by the incomplete adjustment of the residual axial force in the initial design. Now after a long period of research and optimization, the heating problem caused by the residual axial force has been basically solve. In addition, there are the following factors for bearing heating:
1). The rear throttle device wears out due to long-term operation, which causes the bearing to undergo axial force changes and the bearing heats up. 

2). Due to the lack of on-site maintenance during the operation of the pump, excessive oiling or failure to add oil in time leads to increased bearing friction resistance and heat; 

3). Because the bearing is worn out, it has not been replaced in time. 

4). The interference fit of the bearing makes the expansion coefficient of the bearing too low to generate heat.

2. ​Why use double suction structure for the first stage？​

The first-stage impeller adopts a symmetrical double suction structure, which increases the inlet flow area of the impeller, which can effectively improve the cavitation performance of the pump; increase the operating stability of the pump. In addition, the double suction structure at the first stage can play a role in balancing the axial force when in the odd-numbered water pump​