Lubricated gear and roller contacts experience both solid and fluid friction. Their individual shares of friction depend on the lubrication regime, load sharing, and lubricant additives. For asperity contacts, solid friction increases as the pitch line velocity rises, while fluid friction decreases as the pitch line velocity decreases. The lubricant base oil used is also an important factor in the friction regime, as the solid coefficient of friction is higher than the fluid coefficient of friction in mineral oil. Continue reading this article so as to get more information in relation to lubrication of lubricated gear and roller bearings. A plastic-metal composite gear is a highly durable and reliable option for high-temperature applications. The non-lubricated gear and roller system is easy to install and remove for maintenance. This material features a crystalline structure made of cast Nylon 12. Other plastics, including nitrile rubber, are amorphous, with pockets of varying densities. By using a plastic material of uniform density, the plastic gear will be perfectly shaped. The use of lubricant plays a key role in preserving the life of a gear. A gear that is not lubricated is likely to degrade quickly, causing the gear to fail. The type of lubricant used to preserve a gear depends on tangential and rotating speeds, and the materials and temperatures involved in the operation. A lubricant that has the right coefficient of friction (C) and temperature can prevent tooth wear and premature failure. In this page, find a great post to read to get more enlightened about lubrication of gears and roller bearings. A water-containing lubricant has lower viscosity than conventional gear oils. This lower viscosity creates less churning loss, but it increases the potential for thin oil films to form. Oil films can damage mechanical parts. The major failure modes in a tapered roller bearing include bottom wear on the large end face of the roller, also known as bearing bottom wear. In contrast, side wear is wear that affects the rolling contact surface of the rollers. Conventional gear oils and water-containing gear fluids exhibit similar no-load losses to conventional gear oil, but show lower losses at high pitch line velocities. The load-dependent losses of water-containing gear fluids are significantly lower than those of conventional gear oils. These fluids are similar in terms of kinematic viscosity but have higher no-load losses. They both exhibit lower losses than conventional gear oils, especially at low pitch line velocities. Find out more details in relation to this topic here: https://en.wikipedia.org/wiki/Roller_chain.
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