In what is the difference between Mineral and Synthetic Lubricants?
20 Jun '17, 03:37
Mineral or refined lubricants
Mineral oils are refined from crude oil. Refining is an industrial process when physically separating oil components by specific gravity.
Crude oil comprises various kinds of hydrocarbons and contaminants. Some are similar in specific gravity but different in structure. The refining process cannot separate such molecules, so a wide variety of such hydrocarbon molecules contained in the finished lubricant made from crude oil stocks.
Some crude oil ingredients are not beneficial to the lubrication. For example, paraffin causes refined lubricants to thicken and flow poorly in cold temperatures. Molecules containing sulfur, nitrogen and other elements facilitate the formation of sludge and other products of lubricant breakdown, especially in high-temperature applications. Sludge, oxidation and breakdown products significantly increase wear rates.
Various molecules of refined lubricants also have a different structure, making lubricant film surfaces irregular at the molecular level. As lubricant layers slip against each other during the lubrication process, these irregularities create friction, which consumes power, reduces efficiency and increases heat and wear.
The primary advantage of mineral oils is their low cost. The limitation on other hand is that the lubricant molecules have a variety of structures and size ranging from the optimal to the worst.
Synthetic lubricants are produced by chemical reaction(s) from pure ingredients rather than refined from crude oil. It gives great advantages over refined oils. Synthetic lubricants differ from refined on three key aspects: synthetics are pure, their molecular structure is uniform, and they may be designed to work in applications in which refined oils cannot.
Purity - The raw source material from which synthetic lubricants are made do not contain sulfur, nitrogen or other elements that accelerate the formation of sludge and other products of breakdown. Synthetic lubricants used in higher temperature applications than refined lubricants without breaking down. They also have longer service life than refined lubricants. Lubricated systems stay cleaner and last longer with synthetic lubricants.
Uniformity - The ingredients from which synthetic lubricants are made have a uniform and smooth molecular structures. This gives low friction as lubricant layers slide against each other. Reduced friction increases energy efficiency for greater fuel economy and power, reduces heat and wear for longer equipment life.
Molecular uniformity also ensures synthetic lubricants to resist thinning and thickening during different temperatures, which makes them able to protect better than refined oils over a system's operating temperature range and helps ensure secure sealing.
Experience proved that synthetics can give economic benefits when used in place of mineral oils. The benefits fall into five general areas:
- Greater energy efficiency
- Wider operating temperature limits
- Improved design
- Reduced service requirements
- More reliable and safer
20 Jun '17, 04:03