A lubricant is a substance interposed between two surfaces in relative motion for the purpose of reducing the friction and wear between them. Lubricant provides a protective film which allows for two touching surfaces to be separated and "smoothed," thus lessening the friction between them and correspondingly less heat generation in the machine, thereby keeping the working temperature of machine parts within safe operating limits. Wear and tear of parts is thus greatly reduced resulting in fewer breakdowns, greater machine utility, lower maintenance cost and longer machine life.
The recorded use of lubricants dates back to almost to the birth of civilization, with early historical developments being concerned with the use of fats/oils of animal or vegetable origin in transportation or machinery. Ancient inscriptions dating back to 1400 B.C. show early examples of systematic lubrication with animal fats (tallow) being applied to reduce friction on chariot wheel axels. From these very early roots, efforts to reduce friction were dependent on relatively abundant animal and vegetable-based oils.
During the middle ages (AD 450- 1450) there was a steady development in the use of lubricants, but it was not until AD 1600 - 1850 (particularly the industrial revolution in AD 1750 - 1850) that the value of lubricants in decreasing friction and wear was recognized.
Colonel William Drake struck oil on Aug.27,1859; marking the birth of the petroleum industry. He drilled first oil well at Titusville, Pa in America in 1859 and his well-publicized oil well created a new way to supply an arguably superior oil product, which accelerated the move toward the use of mineral oil and hastened the birth of the petroleum age. Petroleum-based oils were not widely accepted at first because they did not perform as well as many of the animal-based products. Raw crude did not make a good lubricant. But as the demand for automobiles grew, so did the demand for better lubricants. Lubricant manufacturers soon learned which crude made the best lubricants. In the 1920s, lubrication manufacturers started processing their base oils to improve their performance. By 1923, the Society of Automotive Engineers classified engine oils by viscosity: light, medium and heavy. Engine oils contained no additives and had to be replaced every 800 to 1,000 miles.
By approximately 1930, solvent processing emerged as a viable technology for improving base oil performance using a fairly safe, recyclable solvent. Additives began to be widely used in 1947 when the API began to categorize engine oils by severity of service: regular, premium and heavy-duty. Additives were used to extend the life only in premium and heavy-duty oils. In 1950, multigrade oils were first introduced which improved the hot and cold performance of the oil. For several decades, the lubricants industry continued to rely heavily on additive technology to improve the performance of finished oils. Lubricant quality improved significantly only when the additive chemistry improved.
Modern lubricants are formulated from a range of premium base fluids and advanced additive chemistry. The base fluids has several functions but primarily it is the lubricant providing a fluid layer separating moving surfaces or removing heat and wear particles while keeping friction at minimum. Many of the properties of the lubricant are enhanced or created by addition of special chemical additives to base fluids.
Today lubricants play a very vital role in the smooth & trouble free operation of any automobile or industrial equipment.