30% to 50% fill Typically used. For very high speeds the lower limit should be used in order to reduce churning and overheating of the grease. Overpacked bearings tend to overheat, and to overheat even more at higher speeds.
Can you over grease an electric motor?
Don’t over lubricate your bearings. Over lubrication can cause the grease or oil to get into the windings. This will cause the insulation to deteriorate around the winding causing arcing and shorting inside the motor to the case. This will cause excessive heat and wear on the rotor and stator as well.
How do you grease an electric motor?
Electric Motor Bearing Lubrication Procedure
- Ensure the grease gun contains the appropriate lubricant.
- Clean the areas around the relief and fill fittings.
- Remove the grease relief valve or drain plug.
- Grease the bearing with a calculated amount of grease.
- Watch for grease coming out the relief port.
How much grease is enough?
Rule of Thumb #1: G = DB/10
This is done by pumping a known number of strokes on your grease gun and weighing the discharged grease on a scale. As an example of using this formula, let’s consider a sealed bearing on a 2? diameter shaft that is 7/8 of an inch wide. (2 x . 825)/10 = 0.16 oz of grease.
How often do you grease electric motor bearings?
In general, for oil bath lubrication where the operating temperature is 50°C (120°F) or less, oil should be replaced once a year. When the operating temperature is between 80°C – 100°C (176°F – 212°F), oil should be replaced at least every three months.
How much grease should you add to a motor bearing?
30% to 50% fill Typically used. For very high speeds the lower limit should be used in order to reduce churning and overheating of the grease. Overpacked bearings tend to overheat, and to overheat even more at higher speeds.
When greasing a motor the worst thing over greasing does is?
Too much grease volume (overgreasing) in a bearing cavity will cause the rotating bearing elements to begin churning the grease, pushing it out of the way, resulting in energy loss and rising temperatures.
Do electric motors need lubrication?
Electric motors require lubricants with specific characteristics. Use of the wrong grease often leads to early electric motor failures. The grease consistency preferred for electric motors is normally NLGI 2 or 3, with a base oil viscosity of 100-150 cSt @ 40°C.
When should I grease my electric motor?
Dropping point: The dropping point is an indication of the temperature at which the grease will melt or the oil will separate from the thickener. A grease with a high dropping point is desirable, given the high temperatures reached during electric motor bearing operations.
How do you calculate bearing grease?
To calculate grease quantity, you need the bearing’s physical dimensions (primarily the outside diameter and width). Once you have these two measurements (in inches), you multiply them together and then multiply by 0.114. The resulting answer is the grease quantity in ounces.
How many ounces are in a pump of grease?
Answer: Generally, a shot of grease means one stroke from the grease gun. However, the output, or amount of lubricant dispensed from a grease gun depends on the model. Grease guns deliver widely varying amounts of grease (typically 0.1 ounce or 2 to 3 grams).
How many shots of grease are in a bearing?
Using the chart and the formula, the bearing only needs 8 grams of grease every 10,000 hours. If your grease gun delivers around 1.35 grams per stroke, that means the bearing needs 6 strokes every 13 months; you could average it out to a stroke every 8 weeks or so.
How many seconds per stroke can you use a grease gun?
Use hand-operated grease gun, not a pneumatic grease gun. Pump grease slowly, taking 10 to 12 seconds to complete each stroke.
Why use polyurea grease in electric motors?
It has very low oil separation, so it will not bleed into the motor’s windings.The LE grease also maintains pumpability at low temperatures, making it suitable for cold environments and for use with long feed lines to remote application sites.
Is Lithium Grease good for bearings?
Did you know a spray of WD-40 Specialist White Lithium Grease is a great lithium lubricant for bearings? It reduces friction on bearings and helps keep them protected from rust as well.Because it’s a superior water and heat-resistant, high pressure grease, White Lithium Grease is great for cars and tools as well.
Do new bearings need grease?
YES, they need to be greased with BEARING GREASE unless you bought the bearing and hub pre-assembled from Timken and spent hundreds of dollars. You DID NOT buy a hub and bearing for $100 so if you think you did you didn’t….you will only be receiving the bearing.
What temperature should a bearing run at?
Normal motor bearing operating temperatures range from 140° to 160°F. As in all bearing applications, this measurement should be taken at the bearing outer ring. If the outer ring is inaccessible, take the measurement at the housing and add 15° to 20°F to estimate the correct bearing temperature.
Can you oil Small electric motors?
Don’t use automotive motor oil! It’s too thin for electric motors. Plus, it contains detergent. If the excess oil seeps onto the motor windings, it might dissolve the insulation and fry the motor.
When should I stop greasing?
You can also avoid over-lubrication by practicing the following measures:
- Stop greasing if you note back pressure that is not normal.
- Check to see that the exhaust ports on a machine are free from debris, including hard crust.
- Slowly pump the lubricant into a machine’s bearings for several seconds.
How many grams of grease are in a pump?
1.28 grams
Manual (Lever) This is the most common type of grease gun and can supply around 1.28 grams of grease per pump, which is forced through an aperture from hand pumps.
What problems can develop if too much grease is used in lubricating an electric motor?
Motor Failure
In instances where bearings are in an electric motor, over-lubricating those bearings can cause serious damage. If the excess grease reaches the motor windings, the windings will get insulated with grease, causing inefficient performance, overheating, and bearing failure.
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