It doesn't sound any noisier (acoustically) than the other two mills on this unit which are identical. I probably should have mentioned this before ... this gear mesh frequency does not show up at all on the other machines, and never has before on this machine. These mills have a lot of noise...
During the overhaul the intermediate gearset assembly was replaced (bearings, shaft, and gears). The high speed pinion gear driven by the motor was replaced. The bullgear that turns the ball mill was not changed. The coupling to the motor is new. The herringbone gears are made of hardened...
I have a pulverizer that was vibrating at 1 ips measured at various bearings within the gearbox. This vibration appeared after the gearbox was overhauled. It is a double reduction gearbox. %99 of the vibration is occuring at 332 Hz, which corresponds to the gearmesh frequency of the first...
