The Oil Mist principle was developed by a bearing manufacturer in Europe during the 1930s. The problem that nurtured this development was the inability to satisfactorily lubricate high-speed spindle bearings on grinders and similar equipment. In 1948, oil mist was brought to the United States in the steel industry. Since'the late 1950% oil mist has been servicing rotating equipment 'in the refining industry. The first use of oil mist in the petrochemical industry was in the Gulf Coast due to the high humidity and condensation resulting in bearing failures. The speed of these bearing was too high for grease lubrication, and liquid oil generated too much heat through fluid friction, necessitating an expensive recirculating system. Continuous thin-film lubrication with Oil Mist provided a solution. The purging and slight cooling effects of the carrier air gave additional benefits.
The Oil Mist generator resulted later from this development and used a small amount of air to produce a dense concentration of small oil particles. About 97% of these particles could be transmitted to the bearings without condensing in the piping, regardless of the distance of the bearings from the Oil Mist generator itself.
In 1958, air heaters were developed because it was discovered that, by heating the air used to generate Oil Mist, oils of just about any viscosity could be atomized. Many applications, subject to extremes in ambient temperature, use air heaters to ensure a constant oil/air ratio regardless of the oil viscosity. Today Oil Mist is still used to lubricate high speed spindles in grinders. Included in the increasing range of Oil Mist applications are systems applied to all types of other machine tools, web and sheet processing equipment, belt and chain conveyors rolling mills, vibrators, crushers, centrifuges, kilns, pulverizers, ball mills, dryers and liquid processing pumps.
Oil Mist is an aerosol with an appearance of smoke or fog. Oil Mist systems are made up of several simple but effective components, which can supply the proper lubrication for electric motor bearings. The main components of an Oil Mist system are the generator head or venturi, reclassifiers, vents and drains. Passing high velocity air over an orifice that pulls oil into an air stream creates the oil mist.
Later the technology was extended in a limited fashion to the petrochemical industry. Initial applications were for process pump lubrication. A great deal of caution was exercised with the new technology and while progress was made, it was slow. Experience in recent years has shown that many of the early concerns were not really applicable and that oil mist lubrication is a very efficient and reliable method for attaining optimum bearing life.
Oil mist is a proven technology that demonstrates every day around the world that it significantly reduces bearing failures, reduces maintenance costs, improves machinery availability, reduces energy consumption, reduces the need for warehoused repair parts, reduces life cycle costs, and reduces the stress of operating a plant. It not only improves machinery reliability but frees up operators and maintenance personnel to perform their primary functions, to put on spec product out the door and to help make the company a profitable business. Oil mist is discretionary but there is probably not another thing that a plant may do that can achieve these level reliability improvements than as can oil mist lubrication. It is also an effective method for lubricating electric motor bearings. Studies have shown significant increases in bearing life compared to grease lubrication.