Two roots blowers, same model and make and addressing the same application. One of them is having problem as described below
1. Pl see the attached spectrums.
2. Frequent bearing failure at location no. 3.
3. High acceleration and enveloping (gE) readings at bearing no. 3,4, & 5. Overall vibration levels in the range of 7-9 mm/sec on all the blower bearings.
4. Similar frequency components in all velocity, acceleration & enveloping spectrum as shown for the bearing no. 3 in the attachment i.e. dominant frequency of 2 X blower RPM.
5. High temperature of bearing no. 3 & 5 i.e. approx 105 Deg C as compared to the another blower which has a temp of approx 78 Deg G.
6. I understand that normally, this type of blowers will have typically vibration levels in range of 6-8 mm/sec. However, I am not sure of the G levels which can be typically allowed on this type of machines.
You expert comments on what could be the possible cause. Pl let me know if any further information required.