News tagged with lubricants
A lubricant is a substance introduced to reduce friction between moving surfaces. It may also have the function of transporting foreign particles and of distributing heat. The property of reducing friction is known as lubricity.
A good lubricant possesses the following characteristics:
One of the single largest applications for lubricants, in the form of motor oil, is protecting the internal combustion engines in motor vehicles and powered equipment.
Typically lubricants contain 90% base oil (most often petroleum fractions, called mineral oils) and less than 10% additives. Vegetable oils or synthetic liquids such as hydrogenated polyolefins, esters, silicones, fluorocarbons and many others are sometimes used as base oils. Additives deliver reduced friction and wear, increased viscosity, improved viscosity index, resistance to corrosion and oxidation, aging or contamination, etc.
Lubricants such as 2-cycle oil are added to fuels like gasoline which has low lubricity. Sulfur impurities in fuels also provide some lubrication properties, which has to be taken in account when switching to a low-sulfur diesel; biodiesel is a popular diesel fuel additive providing additional lubricity.
Non-liquid lubricants include grease, powders (dry graphite, PTFE, Molybdenum disulfide, tungsten disulfide, etc.), teflon tape used in plumbing, air cushion and others. Dry lubricants such as graphite, molybdenum disulfide and tungsten disulfide also offer lubrication at temperatures (up to 350 °C) higher than liquid and oil-based lubricants are able to operate. Limited interest has been shown in low friction properties of compacted oxide glaze layers formed at several hundred degrees Celsius in metallic sliding systems, however, practical use is still many years away due to their physically unstable nature.
Another approach to reducing friction and wear is to use bearings such as ball bearings, roller bearings or air bearings, which in turn require internal lubrication themselves, or to use sound, in the case of acoustic lubrication.
In addition to industrial applications, lubricants are used for many other purposes. Other uses include cooking (oils and fats in use in frying pans, in baking to prevent food sticking), bio-medical applications on humans (e.g. lubricants for artificial joints), ultrasound examination, internal examinations for males and females, and the use of personal lubricant for sexual purposes.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
Think new discoveries are the bee's knees? This one is even better—this research out of Rhode Island Hospital is the mice's knees. Researchers have found that adding lubricin, a protein that our bodies naturally produce, ...
Arthritis & Rheumatism Mar 25, 2013 | 5 / 5 (2) | 1 |
(HealthDay) -- Long-term psychosexual outcomes for patients undergoing vaginal dilation are at least equivalent to those undergoing vaginoplasty, according to a study published in the July issue of The Jo ...
Obstetrics & gynaecology Jul 13, 2012 | 3.5 / 5 (2) | 0
A new study published in The Journal of Sexual Medicine reveals that within a nationally representative study of American men and women, sex was rated as highly arousing and pleasurable whether or not condoms and/or lubric ...
Health Jan 23, 2013 | 3 / 5 (2) | 0