Maintain the bearing so you get the maximum life out of it.
Monitor bearings for early signs of failure. Inspect bearings to detect any problems.
Bearings are designed for specific environments, expected loads and speeds. Be sure that the bearing you have will meet the requirements of the job.
Bearings are used to reduce the friction between machine parts such as rotating shafts and housings. Failed, seized, poorly lubricated or unlubricated, damaged, or misaligned bearings will grow hot with friction.
All bearings will fail eventually. That is why it has long been the practice to check on bearings, even before OSHA existed. A hot bearing only needs fuel and oxygen to start a fire, and that fire could smolder for hours.
Externally mounted bearing sensors on the head section of a bucket elevator.
Failure Prevention
Knowing that bearings will fail, it is up to you to create a system to catch signs of a failure before it happens. One way is to have the bearings properly lubricated.
The person doing the oiling should be the one who inspects the bearing, if possible. He or she should note any change or problems, so that the issue can be remedied. That person also should have training to know the type of lubricant needed, as well as making sure that dust does not enter with the lubricant.
One common problem in lubrication is too much of a good thing. Make sure that employees know that an extra pump for good measure is not a good idea.
OSHA’s Two Cents Worth
The 1996 OSHA grain standard (1910.272) states, “the employer shall promptly correct, or remove from service, overheated bearings and slipping or misaligned belts associated with inside bucket elevators.” Notice the words promptly correct. That does not mean monitor it for a day or two. It means fix it now, or shut the equipment down until you can fix it.
Don’t assume that the bearing monitor will do your work for you. Bearing monitors should be checked to make sure that they are still functioning. Are you getting a reading that makes sense, or is there something wrong with the monitor? People should learn to feel a bearing for evidence of heating, just like a doctor will take a temperature of a patient. When you walk through the elevator, take the time to feel bearings where you can.
Bearings must be mounted externally to the leg casing, or the employer must provide vibration, temperature, or other monitoring of the conditions of the bearings, if they are mounted inside or partially inside the leg casing.
Source: Lynn Larsen, president of Safety Solutions Inc., a safety consulting firm, Knoxville, TN; 701-261-9587.
This Safety Tip of the Week is sponsored by: Industrial Magnetics, Inc.
Externally mounted bearing sensors on the head section of a bucket elevator.
