Bearings are a critical part of the design and function of most mechanical equipment. Sadly, due to improper selection, storage, and installation, the majority of these components never reach their intended design life. Consequences for a plant from these situations can include compromised equipment operation, lost capacity, and increased costs.
A recent post on the Ludeca (ludeca.com, Doral, FL) blog urged readers not to condemn their equipment to death through improper bearing storage. The author, Trent Phillips, CRL, CMRP, offered a number of best-practice must-dos and don’ts to help facilities ensure bearing reliability.
— Jane Alexander, Managing Editor
Bearing storage must-dos
Do store bearings in a clean, dry, low-humidity environment. Moisture from the environment, work gloves, and other sources can result in corrosion and/or etched sections that create fatigue on a bearing. Avoid storage near direct sunlight, air conditioners, or vents.
• Do eliminate the possibility of shock/vibration during handling and storage.
• Do store bearings on pallets or shelves in areas that aren’t subjected to high humidity or sudden or severe environmental changes.
• Do store bearings flat and never stack them. Lubrication and anti-corrosion material could squeeze out of stacked bearings.
• Do (always) lay bearings on clean, dry paper when handling.
• Do keep bearings away from sources of magnetism.
• Don’t store bearings on the floor. Doing so will introduce contamination, moisture, and vibration/shock.
• Don’t remove bearings from cartons/crates or protective wrappings until just prior to installation in a machine. The exception may be bearings in wooden crates, as they could attract moisture.
• Don’t clean bearings with cotton or similar materials that can leave dust and/or contamination behind. Use lint-free materials.
• Don’t handle bearings with dirty, oily, or moist hands.
• Don’t nick or scratch bearing surfaces.
• Don’t remove any lubrication from a new bearing. Lubricants in stored bearings will deteriorate over time. The bearing manufacturer should specify shelf-life limits. These dates should be noted on the packaging and monitored to help ensure bearings are fit for use when needed. MT
Proper storage techniques are just part of the reliability picture when it comes to bearings. According to Trent Phillips, the following visual inspections of bearing integrity should be completed periodically on stored bearings, and just prior to putting them into service:
Examine packaging for indications that the bearing could have been damaged during shipment or storage. The item should be discarded or returned to the supplier if signs of damage are found.
Examine the grease or oil for evidence of hardening, caking, discoloration, separation, and other problems. Re-lubrication for continued storage or replacement maybe required.
Trent Phillips, CRL, CMRP, is global reliability leader with Atlanta-based Novelis (novelis.com). To read more of his insight on Ludeca’s website (ludeca.com), including Part 1 of the two-part post “Has Your Equipment Been Condemned to Death?” on which this Reliability + Maintenance Center page is based, go to ludeca.com/blog.