Note: During the contract negotiations for the equipment, the buyer should insist that the manufacturer?s warranty does not start until the equipment is operating to the client?s satisfaction. 

Often, during new plant construction, equipment will lie in the storeroom without any maintenance for many months, which negates the warranty even before installation and operation. 

When a major component or complete piece of equipment is tested at the manufacturer?s site, it is virtually guaranteed to pass the acceptance inspection because it is set up under ideal conditions. However, when the equipment is being delivered, it is often subjected to abuse during transportation. This abuse is usually not intentional; but in the course of being transported, the equipment can be subjected to vibration, false Brinnelling of bearings (false Brinelling is a fretting-type phenomenon normally caused by vibration while the bearing is not rotating or by oscillating motion of very small amplitude), or improperly placed lifting slings, which allows bending of the frame or bedplate to take place. This can take place two or three times before the equipment is finally lifted into position. The only guarantee that is left is for the client and the manufacturer?s representative to perform a quality control audit at each step of the receipt and installation process. If this type of control is not practiced, you can expect the equipment to experience problems that will place it in a reactive-maintenance mode over its operational lifetime. 

When spare parts and components are to be stored for a lengthy period, the storeroom should have a maintenance program in place and a maintenance schedule set to perform periodic tasks to ensure that those components and parts will always be ready to use. 

The following guidelines are based on manufacturers? storage instructions and my past experience.

Motors should be rotated at least 4½ turns every two weeks to prevent false Brinnelling of the bearings. This is to ensure the bearing?s rolling elements are lubricated during rotation. The extra ½ turn takes the rotor shaft off of its last standing position, thus preventing further loading at the previous rotor location.

To ensure that grease is suitable for use in certain bearings, all recommended greases should be color-coded and the grease guns suitably colored to match that particular grade of grease. The amount of grease that is delivered from one stroke of the grease gun should be weighed and inscribed permanently on the barrel of the gun for future reference.

Before greasing bearings, ensure the correct grade of grease will be used and determine how much is to be applied. Bearing grease should be checked at least twice a year to ensure there are no signs of separation or                       contamination. Also check that the grease nipples are clean. As an added precaution, installation of plastic caps over the nipples should be used to color-code to match the grease guns, to protect the grease nipple ports, and to prevent ingress of dirt into the bearings during greasing operations. Add make-up grease to each bearing cavity with its vent drain plug removed to permit excess grease to vent. During greasing operations, turn the shaft by hand to ensure even distribution of grease within the cavity. When the excess grease stops venting, replace the drain plug and wipe the area clean with a lint free rag. 

The lower half of a bearing should be 1/3 to ½ full when the bearing cavity is correctly greased.

Motors heaters (if fitted) should be checked on a monthly schedule to ensure that the heaters are energized and that there is no sign of condensation forming on the windings. Insulation tests should be performed at least every six months.

Motors should be stored in a controlled environment and kept off concrete floors to avoid dust collecting in the vents and windings. Avoid areas of dampness and direct exposure to fans or vents.

Bearings

Note: Bearings must always be considered as precision products and, as such, they must be stored in a clean, temperature-controlled environment.

Users often stock bearings in fairly large quantities. However, even though the manufacturer takes precautions to deliver quality products that are properly packaged to withstand long periods of time, damage often occurs in the storeroom. New bearings can be damaged if they get too hot, are stored in damp or extremely dirty locations, if packing boxes are opened and then improperly resealed, or someone drops them. Once these protective properties are lost, the bearing can rust from having lost its protection against dampness.

New bearings are shipped in plastic sealed bags or wrapped in moisture resistant paper.

Do not use newspaper or ordinary untreated paper. These products have a blotting effect and will soak up oil or grease; they also have an affinity for moisture and should never be used to protect new or used bearings in long-term storage.

The following precautions must be observed to prevent bearings from getting dirty and rusty:

• Never store bearings next to steam lines, a furnace, or in unusually warm areas within the storeroom. 
• Never store bearings where direct sunlight hits them as this will melt factory-protective coatings. 
• Never let bearing boxes or wrappings become excessively dirty or wet.
• Never handle bearings with bare hands if boxes or wrappings are opened and improperly resealed. The natural pH balance of the human body is very acidic and can cause corrosion in bearings that have been touched by bare hands. 
• Never use untreated paper to wrap bearings that are being returned to stock. 
• Never return bearings to stock that have not been properly lubricated with grease. Grease should be worked in between the balls or rollers to coat every surface, including the inside and outside of the races to prevent rust formation on uncoated surfaces of the metal. 
• Never use compressed air to blow-dry bearings after cleaning. This is a dangerous practice that can cause the rolling elements to spin at high speeds, which can shatter the more-brittle outer race and severely maim or kill someone. 
• Never use cotton waste or dirty clothes to wipe or handle bearings.
• Lint and other foreign matter may cause serious damage. 
• Never polish out nicks and abrasions with emery cloths. 
• Never bump or drop bearings, even on soft wooden surfaces, as this will jolt the rolling elements against the cages causing minute indentations. This is usually referred to as false Brinnelling.