A dilemma every industrial facility comes to time and time again. An electric motor in your facility has an issue, it could be a vibration issue, bearing issue, or a variety of other items. Now is decision time... should you remove that motor from service and send it out to a motor repair shop or should you ask the motor repair shop to come to you and service the motor right where it sits?
There are a variety of factors that should go into making this decision. Here are some of the major factors that you should consider:
1. Whats wrong with the motor?
What do you think is wrong with the motor? If its a rewind, much more difficult to do onsite. Is it a bearing change? Ok- this is possible many times but there are many other factors to consider. What caused the issue within the motor? By changing it onsite you are not doing any machining to correct a tolerance issue or fully dismantling the motor to check everything. You also do not have lathes and all of the equipment that you have in shop to check items. So although it may be possible, it may not be the best long-term option for your motor. However, there are plenty of scenarios where simply getting by another month or two is needed for production. Only you can make those calls and decided long term reliability versus short term production needs. One last note, keep in mind that many times more needs to be done to a motor than just what the obvious issue is. When you are in the field you are limited on what you can do and many times the motor still needs to be pulled at a later date. So many times when you repair it in the field, its somewhat like kicking the can down the road a bit.
2. What is the motor?
What is the motor that needs to come out? Is it a large machine that will require you to call in millwrights to remove, or is it a smaller motor that can easily be manhandled and moved by your own personnel. No matter if its large or small, you must look at all options here and understand what it will take. Is it a 3600RPM motor? A 2-pole motor is a higher speed motor that can cause issues with a minor anomaly. These should probably come out to a shop 9/10 times. A larger motor is many times your most critical motor in your facility. Is it worth the issues that can happen onsite and not being in a shop and prepared for most issues that could arise?
3. What is the environment the motor is in?
A good, quality electric motor repair shop should be pretty clean. Many industrial facilities have very dirty processes that take place and cause the environment to be pretty rough. If you are working on a motor in a dirty environment it can create many other issues down the road. A dirty environment with a sleeve bearing motor, doing sleeve bearing repairs can lead to dirt and contaminants getting into the oil sumps or bearing themselves causing issues. A totally enclosed motor is protected from the environment, when you open it up in the field you are now exposing it to the environment, if contaminated get inside the motor it can cause winding, bearing, and many other issues. This is a factor that should be considered when evaluating doing a repair in the field versus in a shop.
4. How fast does it need to be done?
Many times the issues that lead to a repair being done in the field is due to a time issue. There is simply no time to pull the motor, transport it to a shop, repair it, transport it back to you facility, and re-install it. Therefore, doing it in the field is your best option. One item to keep in mind here is that it does take longer to perform tasks in the field versus in a shop. Typically what takes extra time is unexpected items that arise, not having the right tool with you, and space constraints around your working area. These all go away when you are in a fully-prepared shop. However, there is no way to get around the travel time required for transport.
There are a lot of factors and variables to consider when you are determining to pull a motor and send it out to a vendor for repair or just doing the repairs on-site where the motor currently sits. If you expect a minor anomaly that is easily accessible in a motor that is in a pretty clean environment, but would take a lot of money to rig it out and the repairs needed to be done yesterday, then it sound like an obvious choice to go ahead and fix it onsite. However, if its a major issue, in a dirty environment, in a 2-pole motor, you may want to just go ahead and bite the bullet and pull it out for repair.
Only you can make the determination on what to do. You know your plant, production needs, and maintenance history better than anyone else.
Justin T. Hatfield
HECO - All Systems Go
About the author:
Justin T. Hatfield is Vice President of Operations at HECO. He is responsible for Electric Motor & Drive Sales, Electric Motor & Generator Repairs, Spare Solutions, and Predictive Services. Justin was instrumental in developing HECO MAPPS (Motor and Powertrain Performance Systems) which focuses on “why” you have a motor problem instead of simply “What” product or service should be recommended. HECO is an EASA Accredited Service Center for Electric Motors as well as a provider of predictive maintenance services and products throughout the United States.