Most industrial food-grade mold release agents contain silicone oil in amounts varying from >0.1% to 3%. A very small number of food-grade release products contain soy bean oil primarily for the release of industrial baking equipment from the food product. The silicone oil can withstand a higher temperature than soy oil and does not brown and become sticky after repeated heat applications. For these reasons, silicone oil is more practical, although more expensive (at between $26-$52/case of aerosol cans) for most food release applications.

The silicone oil is, in general, inert and can be used in contact with food (as regulated by the FDA) as well as other materials. The oil serves to lubricate the contact surfaces and allow separation when one surface slides against the other as during mold cool-down. When combined with some force from mold ejection pins, the food product easy separates from the the mold surface.

However, when two parts coated with silicone oil are stuck together by a vacuum, the silicone oil promotes sliding but not a release from the vacuum inless the parts are slid completely apart. Usually, the vacuum must be released by either prying the parts or by lowering / eliminating the vacuum pressure between them.

For rolling element bearings an oil may be preferable as viscous dissipation (hence, traction torque) would be minimized. For high speed applications (~100,000 DN) grease can not be used. The downside is that for a non-recirculating system the oil would have to be replaced more frequently. Consideration must also be given to additives such as oxidation inhibitors, EP (extreme pressure) additives, etc., as these may be required for specific applications. For example, EP additives are typically added to 80W-90 oils used with taper roller bearings having high edge loads as is found in a gearbox applications.

Greases are preferred where maintainence requirements are to be held to a minimum and where a re-circulating oil system is not feasible. Further, grease packed bearings tend to be more tolerant of contamination.

The application has to be defined. For example, a car wheel bearing is a low speed application but is always grease packed since it isn't routinely serviced. Overall, for low speed applications, except for inline skating, grease is almost always used because it requires low maintenance and no oil supply system.

The effects of corrosion are very important and should be considered for every piping network design. Depending on the purpose of the network and the importance of maintaining cleanliness of the fluid, either corrosion resistant piping or corrosion inhibitors should be used to maintain the integrity of the pipe pressure boundary. For example, networks designed to convey and contact food or other fluids that cannot be contaminated require corrosion resistant piping to prevent or limit foreign (unknown or undesirable) chemicals from leaching into and being absorbed by the fluid stream. Networks designed to contain nonfood products and fluids whose chemical composition can change over time are strong candidates for the addition of corrosion inhibitors to the fluid to prevent pipe corrosion.

There are cost considerations for selecting one mode over the other. Normally, corrosion resistant piping will be significantly more expensive (ranging from 1.2X - 8X higher) than using carbon steel, iron, or common plastics with corrosion inhibitors. However, corrosion inhibitors require procedures for safe handling, disposal, and periodic testing to maintain effectiveness over time. Some inhibitors can also pose dangers to personnel as the chemicals evaporate and are released from the network to the atmosphere.

In either case, the designer must choose a mode for corrosion control or design extra strength and longevity into the system. And because different piping materials react differently to different liquid environments (stainless may not be the best for all environments) it is important to consult with a qualified materials and corrosion expert.