We have one hollow shaft mounting, two input gearbox having gear ratio 14.3 to drive paper machine drying cylinder. It is pivoted at one side and driven by two D.C. motors of 210KW with cardon shafts. Gearbox has high vibration levels in vertical direction opposite to pivot end.
At 750mpm ( 945 input rpm), we get max vib.at gearbox in H & A direction @4mm/sec. and 11 mm/sec in V direction opposite to pivot end. Mostly at 1Xrpm & 2Xrpm of input speed.
Is it safe to run at such high vib.? What may be the cause for vib? How can it be rectified?