Calcium Grease Definition
Calcium greases were the first, followed shortly after by the lithium and barium greases. Calcium grease became commercially available in the late 1940s. While they offer both water and heat resistance, they can be sensitive to water-becoming firmer or softer under different conditions-and, if overheated, they tend to harden. They do, however, carry high loads in operating bearings without the addition of extreme pressure (EP) additives Complex soap-based greases were developed to improve the heat resistance of previous simple soap based greases. Combinations of additives and oils are carefully selected to maximize the performance of the greases. They generally have good mechanical stability, low-temperature pumpability some will even have good reversibility characteristics and will operate at temperatures which are moderately high. Their dropping point may be 100°F. to 200°F. (38°C. to 93°C.) higher than the dropping point of corresponding soap greases. They are generally formed by reacting a common base with two dissimilar organic acid compounds, such as a normal soap base and complexing agents, generally of short chain metallic or organic materials and made “in situ” (in place) in the grease kettle. This makes greases to meet more demanding requirements. Briefly, typical lithium-based greases (the most common) are made from a fatty acid, usually 12-hydroxystearic acid, and a lithium base to produce a simple soap which acts as the grease thickener. Components are then added to give it EP and other desirable properties that allow equipment to run at peak performance. In the 1930s and 1940s, researchers started to find new thickeners for “multipurpose” greases.
Lithium Grease Applications
- Recommended for lubrication of wire ropes metal cables, chains, slide rail and open gears found in marine off-shore and industrial applications.
- Can be used in all types of anti-friction and plain bearings
- Suitable for miscellaneous components (More Info) such as gears, cams, slides, etc.
- Excels in EP performance
- Automotive applications such as chassis, ball joints,(more) universal joints and wheel bearings
- Industrial applications such as continuous casters, conveyors, ball mills, crushers, off-shore and underwater applications.
- Used in motor-operated steam valves to control high-pressure steam(More Info) These steam valves are typically found in nuclear plants and thermal-generating stations(more) An article in NLGI Spokesman, July 20022, supports that the calcite particles, inherent in calcium sulfonate greases, make them a good choice for high-temperature applications.
- Beneficial for rust performance (More) Calcium sulfonate greases are generally beneficial for rust performance, with oxidation stability considered good or excellent. Rust inhibitors are surfactants that neutralize acids on the surface of metal. They can also make an oily surface, or barrier, to stop rust on the surface. Although the thickener can affect oxidation, it is often based on the oil’s quality.
- In summary, if the application requires H-1 approval, heat resistance or water tolerance, a properly manufactured calcium sulfonate grease that meets your needs may be worth the price.
Calcium Grease CHARACTERISTICS
- Very adhesive.
- High temperature resistance
- Excellent water resistance for general lubrication under very severe conditions ( heavy loads, shocks, vibrations, dust and water ).
- High Dropping point ( The drop point is above 300°c
- Good EP properties
- Excellent properties at high loads due to the high viscosity base oil and Calcium Sulphonate complex
- excellent mechanical stability in roller bearings (all kinds of bearings) slide ways and joints
- excellent oxidation and corrosion protection
- Lubrication intervals are greatly extended as well as reducing maintenance and costs.
- Good shear stability
- Long life in storage and in service.
- Highly resistant to ”bleeding” or separation
- Unparalleled rust and corrosion protection – semi-permanent protection of metal surfaces.
- Will not wash off — excellent resistance to water washout and water spray off.
- Handles low-speed, heavily loaded equipment-natural extreme-pressure properties and heavy base oil.
- For use with no food contact.