yankee gear box

[giamma]

Hi to everyone, this is my problem on a paper machine.
This is the part of machine that I have measured

cardan shaft
Motor 1---------------
gear box-------Yankee
Motor 2---------------


I have measured an high vibration on a Yankee's gearbox (17 mm/s RMS in radial direction and 7 mm/s RMS in axial direction), the spectra show only one peak of vibration at 1xRPM of the entry shaft, an the time domain is sinusoidal (for radial and axial). I have only a measurament and I don't know if the high vibrations are present at higer speed, but i know that the cardan shaft are new.

Have you some suggest to give me?

Thank you.
Andrea

 

[unclesyd]

How many Cardan Joints are on each shaft?
If more than one are they in phase, aligned?
How are the shafts coupled to the gearbox?
What is the speed of the input shaft?
What is the centerline offset of the input shaft?

Come back with a little more information

 

[ronfrend]

Hi Andrea,

I have seen exactly the same vibration on a paper machine drive with the same layout as yours and it was caused by misalignment of one of the carden shafts. Carden shafts are extremely sensitive to alignment and they do give high vibration levels if not aligned very carefully.

Ron Frend
tel: 011 44 1253 400541
ron.frend@predicon.net

http://www.predicon.net

 

[Rob45]

One more thing about cardan shafts: just because they're new does NOT mean they are right:
you can look for:
bent shaft
unbalanced shaft
excessive coupling runout
oversize yokes

all on "new" driveshafts; quality control particularly with new Dana shafts is haphazard at best.

 

[GregLocock]

You forgot sticky needle rollers due to incorrect end loading - if the joint doesn't flop over easily in all directions try 'adjusting' it with a hammer.

I've had cars that I couldn't balance due to this.





Cheers

Greg Locock