Cleaning Stator Winding

have you considered ice blasting? no hazardous solvents to contain and clean/dispose of after.

Over the years I have taken the pressure washer to a few motors while they where apart for bearing changes.

I usually blow them dry with an air hose them re megger them afterwards. If I had a questionable reading that was not in the same range as before I cleaned them I will let them air dry for a few days or pass a fair but regulated current from a welder through the windings until they warm up enough to dry themselves out.

I have always avoided pressure anything when cleaning windings- you can damage the insulation, or, at least, force any dirt or grit deeper into the windings where it can do some serious damage to the insulation as the wires heat up and cool down. Usually, the only recommended cleaning method for generator windings from the manufacturers is to use an appropriate solvent, then rinse with low pressure water. Be sure the solvent is appropriate for the application- wrong solvent will take the lacquer insulation off the wire. Drying is absolutely critical- people that do this for a living generally bake the windings for extended periods...

Avoid excessive direct pressure...could damage windings... Try soap & water ..then dry it in an oven... re varnish & bake it...

See the following settlement on CR-4

Forum Thread: Motor externally by spraying water?

first you have to ask, does it really need cleaning?

If so then as it was mentioned use soap and water, nothing else. I use to clean ESP motor stators, which can be over 15 foot long by placing a soft brush "pig" in the stator, capping both ends off and injecting warm soapy water (low pressure) at one end to push the "pig" along, then the automatic washer would then reverse the process.

After about an hour the grime was removed, we then would connect the stator to 3 ph 110 volts for 48 hours to dry the stator and then test the insulation.

I guess you are using a surface type motor, so the best way would be to use warm soapy water and clean it by hand using a soft brush, but you must dry it out and test.

Hi Guest,

As a rule of thumb;never add or introduce water into a winding! You may direct an air stream over the coils but don't spray high velocity anything directly into the coils as insulation may be separated by virtue of the windings moving.

As has been said already oily dirt is not necessarily a problem,as hygenic appearance is not an issue.

Professional re-winders use solvents not usually available over -the-counter, it depends on the type of lacquer used. In the past CCl4 (carbon tetrachloride) was a popular cleaning agent. 'Stoving' to drive out any moisture always formed part of the refurbishment.

I suggest you avoid any water or similar treatments in the interests of avoiding future problems,

Good luck,

Massey.

In our Plant we used De-Greaser specifically designed for Electric Motors. its very popular and available in the market go check with your supplier.

Remove stator and clean coil properly with smooth fine(soft) brush using Tina spirit or fuel in light application for quick dry than water.

After cleaning or brushing off oil stains,deposits and or dirts,allow to dry up as it usually dry up fast(evaporation).

Apply vanish in little quantity if necessary and allow to dry in sun or oven or any other good method.Megger test if necessary,re-couple and power.Yr motor will run fine.

Patrick Whowha

CO2 technology is latest technology which is used to clean the stator windings.

You can also go ahead with this also, but it will be little bit costlier.

I worked in an electric motor repair shop where we did every level of needed repair . . . in the early years we used naptha with an air-syphon feed to wash the stators. This produces a fine mist of naptha which is an excellent degreaser. Then shifted to steam cleaning. The steam cleaning leaves an oily film, but was a lot less expensive than the naptha. Allowing the motor to air dry afterward. After air drying depending on the condition of the varnish on the stator it was sometimes necessary to dip and bake the stator. All motors were subsequently meggered to determine condition of the winding. I was the helper doing the cleaning. I have done this routine on hundreds if not thousands of motors ranging in size from fractional horsepower to 500 horsepower. Naptha is hazardous in many ways, it will cause dermatitis and is a fire hazard . . . so be careful with it.

compressed air , soap and water....

try using dry ice blasting. its the best in the business right now.