What grease for motor bearings
Ignoramus27020
some attention to the motor. The motor is a 40+ year old Reuland
motor. The only problem with it that I observed is that it
squeaks/squeals at 60 Hz. This is not the sound of the VFD frequency,
either. It is irregular squeak/squeal.
I suspected the bearings.
This motor has regular 6306 bearings inside and I will get the
replacements tomorrow. The ones in the motor were double shielded
bearings and that is also the replacement that I will be getting.
My first question is regarding the grease. The motor has no grease
fitting. The bearings were generously covered in grease. I would like
to know if I need to do the same with the new bearings, or it is
optional. Also, can I use white lithium grease.
My second question is about the dirt in the motor. The motor is quite
dirty inside, windings being covered with black dried
oil/grease/muck. I would like to remove that stuff, but safely, so I
am concerned that chemicals like oven cleaner or carb cleaner could
somehow deleteriously affect insulation. Has anyone successfully
cleaned old motors like that, thanks.
i
sta...@prolynx.com
If they're double-shielded, they're greased from the factory, good for
life(of the bearing). Apparently the shielding worked if the innards
were that filthy. Usually, motors were dipped in varnish to
impregnate the windings and then baked. The stuff is fairly resistant
to solvents, I'd wipe, not dunk and check out a non-critical spot
first. Caustic will probably turn the varnish to soap, I wouldn't use
oven cleaner. VM&P naptha would be what I would try first, you might
want to check with a motor rewind shop to see what they'd use. The
naptha shouldn't dissolve the paint, either, it's supposed to be used
for paint prep to remove grease and not leave a deposit.
Stan
Martin H. Eastburn
thickness of a coat needed. The thin high voltage coatings we have
on modern windings allow more copper turns and higher power in the
same package.
Chemicals might dissolve the varnish and require the motor to be
rewound. The best info is from a motor repair man.
They might not know as they 'burn' by oven cooking the winding
to strip out the copper and clean the iron.
Martin
Donwill
2nd Q/
TOTALLY DISCONNECT from electrical supply :-) .
We used to wash dirty armatures and windings in petrol ( I guess what
you would call Gas) and a 1ins paint brush. I hope I don't have to
remind you about the flammability of Gasoline, (otherwise forget it.)
Dry thoroughly, preferably outside in the sun.
If you don't fancy doing that, wash the windings in water with some
mild detergent e.g washing up liquid (safe for your Hands :-) ). rinse
well with clean soft water, final rinse with distilled or deionised
water, dry in well ventilated oven at about 50deg C for approx 2 days.
I 've often done this with electrical items, and even Printed circuit
boards carrying micro amps, they were OK providing they are well dried
afterwards.
Note!! pure water is a Non-conductor of electricity.
Don