We have a problem in our gearbox related to vibration on high speed shaft both ends horz and vertical and on base bolts. Vibration transmitting to 2nd shaft ( Intermediate shaft ) also.
Observed Abnormal Vibrations on Gearbox Input and Intermediate shafts, particularly on horizontal 5.5 mm/s and 7.0 mm/s and vertical 6.4 mm/s and 5.8 mm/s respectively recorded today. Also High G’s Values on Input and Intermediate shafts 2.6 g’s and 2.9 g’s respectively along with significant impacting & abnormal High Noise.In a Spectrums found Gear mesh Frequencies of Shaft 1 to shaft 2 occurring on 38th order with relative peaks and harmonics. Also some bearings faulty peaks affected by gear meshing vibration energy. In a waveform high level of significant impacting and amplitudes modulations present once per revolution.However amplitudes of sidebands with GMF are still low and constant and some times fluctuates.
Found High Vibration on Super bolt 1 particularly on vertical direction between 7 mm/s to 9 mm/s continuously and 1.9 mm/s on horizontal. Also on other all three bolts vibration on vertical direction is higher than horizontal. Collected Phase data between Super bolt base and concrete base in vertical direction, giving 165 degree phase difference,. So what I should suggest to Management for maintenance? Need you Opinion.
I have attached the readings and spectrums waveforms.