Hi expert engineer,, could you please help me for my issue below :
We commissioned a new pump with new electric motor (315 kw, 546 A, 2985 RPM, 50 Hz), but we have get rising in temperature (overheating) in the MTR DE bearing crazily during first four hours reach to 107 °C, so we stop the motor immediately and the problem still come after run the motor (for two days), so we have decided for opening its shield bearing housing cover (single type) to inspect bearing greasing (proper initial quantity , proper distributed, over greasing or lack of greasing), but we found the bearing greasing well also the initial quantity of grease good also,, for satisfying we have greased the bearing by hand in the some gaps between the balls, after that we run the motor again ,, but the rising of temperature problem @ bearing still (same as before). We have check motor vibration and bearing shock pulse by spatial device we found the motor in perfect condition (max vibration reading reached to 1.8 mm/s and Carpet value -5 & max value 4)
So your help required plz to solve this issue and my questions:
1. Is this rising in the temperature normal for new motor? (Bearing type TKN 6317 C3).
2. Are there other reasons than those related to greasing?
3. Are there any related to motor Hz in bearing overheating ( max. Hz reached 46 Hz )?
4. Practical solution for solving the problem