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THE IMPORTANCE OF PROPER GREASING FOR MOTORS AND PUMPS

3 min read

WHY CORRECT GREASING MATTERS? 

Service managers need to make sure that motors and pumps run smoothly and last a long time. One important part of keeping these machines in good shape is greasing the bearings properly. Many people think that using a lot of grease is good, but this is not true. Too much grease can actually cause problems. This article will explain why using the right amount of grease and the right type of grease is so important.

common misunderstandings about greasing

A lot of people believe that more grease is better for bearings. But adding too much grease can create too much heat and pressure, which can damage the bearings. This can lead to more friction, broken seals, and eventually, bearing failure.

Smaller motors and pumps often have sealed-for-life bearings. This means these bearings don’t require any extra grease and grease nipples will not be fitted. So, these bearings will require replacement when they become ‘dry sounding’, or noisy.

main reasons for bearing problems 

The most common reasons for bearing problems are:

  1. Misalignment: Bearings need to be aligned properly to work well and avoid wearing out quickly.
  2. Wrong Grease: Using the wrong type of grease can damage the bearings. Always check the equipment nameplate for correct grease type & quantity. If this is not stated consult the Original Equipment Manufacturer or Supplier to determine the correct grease required. Using a type of grease that is different or incompatible with the grease already within the bearing is the most commonly unknown and serious contributor to premature bearing failure.
  3. Too Much Grease: Adding too much grease can create too much pressure and heat, leading to bearing damage.
  4. Not Enough Grease: Not having enough grease can cause too much friction and heat, leading to quick wear and tear.
  5. Contamination: Dirt or water can get into the grease and cause damage to the bearings.

How to grease motors properly?

To grease motor bearings the right way, follow these steps: 

When the Motor is Stopped: 

  1. Clean the Area: Clean the grease nipple and the area around it to keep dirt out. 
  1. Remove the Outlet Plug: Lift the grease inlet protection and remove the grease outlet plug. For Some motors won’t have this provision, so you won’t be able to complete this step. 
  1. Add Grease: Pump in half the amount of grease shown on the motor’s nameplate. 
  1. Run the Motor: Run the motor for about one minute to spread the grease. 
  1. Add More Grease: Turn off the motor and pump in the rest of the grease. 
  1. Put Everything Back: Put the grease cover back and reinstall the grease outlet plug. 

When the Motor is Running: 

  1. Clean the Area: As before, clean the grease nipple and area around it. 
  1. Remove the Outlet Plug: Lift the grease inlet protection and if it’s safe, remove the grease outlet plug. 
  1. Add Grease: Pump in the full amount of grease as shown on the motor’s nameplate. 
  1. Put Everything Back: Put the grease cover back and reinstall the grease outlet plug. 

Always use a manual grease gun. During the first time you add grease, it might not come out of the outlet due to the internal design. Don’t add more grease expecting it to come out, as this can cause over-greasing. 

using the right grease

It’s very important to use the right type of grease. For example, Mobil Polyrex EM grease required for WEG brand electric motor is not compatible with other types of grease E.g. Lithuium based! Mixing different greases can cause problems. If you need to switch to a different grease, first seek approval from the manufacturer on what grease is acceptable. Then proceed to clean the bearings and lubrication channels before applying the new grease.

Conclusion 

Proper greasing is key to keeping motors and pumps working well. Too much grease, too little grease, or the wrong type of grease can lead to serious problems. Service managers and technicians should make sure their teams know the right way to grease bearings and use the correct type of grease. It may even require keeping two or more grease guns loaded with different grease types in your service vehicles. Always consult the Instruction Operation Manual for the correct grease to use. This will help avoid common problems and keep motors and pumps running smoothly.