Proper lubrication is important because without it there are many ill-effects such as higher than normal wear and tear, decreased machine accuracy and decreased production efficiency. As a result, lubricants are essential to maintaining efficiency and decreasing costs.
Grease, one of the more common lubricants, works exceptionally well for machinery that does not need to be lubricated too frequently. Because grease is such thick and viscous oil it will stay in positions that liquid oil from an oil dispenser would not. Formed from a mixture of oil and soap, various additives can be introduced into the mixture to develop desired characteristics. For instance, Teflon is a possible additive to grease that produces enhanced lubrication properties.
Commonly seen in the automotive industry, grease dispensers are essential in a wide range of industries including industrial manufacturing, for the lubrication of various process and assembly machinery; pharmaceutical, for use in research laboratories for the lubrication of glassware such as stopcocks and ground glass joints; food and beverage, for the lubrication of processing and packaging equipment; and construction, to lubricate various equipment and supplies such as hand-operated power tools.
Grease functions as a shear-thinning lubricant, meaning that its viscosity is reduced under shear, which is defined as stress that is applied in a parallel or tangential manner rather than normal stress, which is applied in a perpendicular method. When a sufficient level of shear is achieved, the viscosity of the grease drops and becomes similar to that of liquid oil, thus functioning as a lubricant.
Grease dispensers generally consist of three essential components: a pump, a gear set and some kind of control system or feature. Most grease dispensers have a motor, but since they can be powered in a couple of different manners including manual, electromechanical and pneumatic, they could also be powered through a hand-lever.
In terms of what kind of pump is used, grease dispensers often use a positive displacement pump, which functions by trapping a fixed amount of grease and then forcing it into the feed lines. The grease is taken from the reservoir, which is a container that stores the grease until it is needed to be dispersed or once the grease has left and returned again from area of lubrication.
Grease dispensers can feed one or more areas of lubrication. Grease dispensers that have a single point of lubrication are used on small machine applications, while grease dispensers with multiple points of lubrication are used for medium to large sized machines.