Single row deep groove ball bearings are used。

When roller bearing（NU-or NJ-）is used in drive end,the electric motor will bear bigger radial strength,which is suit for belt driving。

Greasing for inverter duty operation When the electric motors are matched with frequency inverter, the bearing temperature change as a result of speed and load change.

Measuring its temperature under normal working conditions can get accurate greasing interval. When the temperature is higher than80℃, then greasing interval need shorten, or use high temperature grease.

Greasing Interval For open ball bearings, grease regularly with Li-base grease ZL、 -3.2Poles electric motors are greased each 2000 working hours,4-16 poles electric motors are greased each 3000 working hours. When working temperature is higher than 70℃, greasing interval will be halved each 15℃ temperature rise.

Drain Hole When the electric motors are working in damp or humid place, or operation for intermittent load, drain holes are necessary. Please list IM code in purchase orders.