Motor bed construction
Motor bed construction
(OP)
I recently saw a motor bed of a 3.3 KV, 2000 HP, 1500 RPM motor made up of 8" x 3" boxed up channels welded intermittently at the 3" sides. (The 8" sides were vertical).
What struck me was that the motor was sitting on the welded edges of the channels (3" sides). (There were no welds where the motor was seating.)
The bed was vibrating whenever the motor was loaded (it was a rubber mixing mill called banbury with multi-stage gearing). I could feel the vibrations standing on the bed.
Is this type of motor beds with boxed up channels good / acceptable ? (I prefer 'I' beams instead of channels)
*Nothing exists except atoms and empty space; everything else is just an opinion*





RE: Motor bed construction
RE: Motor bed construction
Could you pls clarify your post about the movement of the motor ?
Thanks again.
*Nothing exists except atoms and empty space; everything else is just an opinion*
RE: Motor bed construction
*Nothing exists except atoms and empty space; everything else is just an opinion*
RE: Motor bed construction
RE: Motor bed construction
1 - should be mounted on cement foundation with mass 5x the mass of the rotating machine
2 - The triangle from the bottom outer corners of the cement to the shaft centerline should be an equilateral triangle or shorter.
3 - foundation should be 6" larger than baseplate for large machines.
The reason for the weight I believe is to minimize vibration of the rotating equipment.
The reason for a stiff base I believe is to prevent distortion under the various loads include weight, torque loads from motor, in your case radial loads from the gears. There are devices such as permalign which can measure actual movement from off-line to running which presumably would detect movement associated with base flexing.
I don't have any standards or references handy. I know API has some standards which are very specific on base construction
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RE: Motor bed construction
(T tried to give a LPS for some reason I am not able to. Must be due my accessing the net throught my mobile.)
*Nothing exists except atoms and empty space; everything else is just an opinion*
RE: Motor bed construction
edison123; I would be looking into the possibility of filling the boxes with grout or concrete. With a Hi-Early (28 Hours to cure) strength cement you may possibly complete the work during a weekend shutdown.
respectfully
RE: Motor bed construction
RE: Motor bed construction