Lubrication Systems

View A Video on Lubrication Systems- A Quick Introduction

Lubricating systems are essential components in many industries and applications including: automotive, where oil dispensers provide clean oil to the engine as well as to maintain proper temperature and pressure; industrial manufacturing, which use chain oilers, grease dispensers and automatic lubricators for the lubrication of conveyors, pumps, electric motors and many other types of vital assembly and process equipment; oilfields use petroleum as a lubricator for machinery such as cranes, generators, top drives and more; the power generation industry utilizes lubrication equipment such as a central lubrication system to maintain proper system lubrication from within the turbine island in the power plant; and steel processing, for the lubrication of equipment such as dust collectors, furnaces and kilns. Primarily used in equipment with rotating or moving parts, additional industries, such as construction, food and beverage, printing, wastewater and mining, all utilize a variety of lubrication equipment, including air lubricators, grease pumps and oilers such as constant level oilers.

Lubrication systems are broadly categorized as either manual or automatic. When they are automatic, lubrication systems are typically a centralized, or permanent, form of lubrication system. Centralized lubrication systems use an automatic lubricant delivery method in order to lubricate more than one machine part at a time. Most commonly, centralized lubrication systems are a part of the machines that they lubricate; however, they do require separate maintenance. Some benefits of automatic lubrication systems are that they reduce downtime and labor cost since they do not require operators, and also decrease the potential for human error since the machines operate in response to programming. The human error factor remains a problem with manual lubrication systems since they are either completely human-operated, such as with spot lubrication guns, or only partially human-operated, like with chain lubricators. Chain lubricators require the mounting of the machine to the chain and the programming of flow rate and length of chain into the device, which is then able to run automatically. Another disadvantage of manual lubrication systems is that there is often an increased chance of "famine or flood," which refers to the lubricator completely missing an area or over-lubricating an area.

There is a wide variety of different lubricators that can be incorporated into lubrication systems, and some of the more common ones include oilers, grease dispensers and air lubrications. Oilers, which are also known as oil dispensers, include a vast array of types including constant level oilers and chain oilers. Primarily, oilers are devices that function to provide lubricating oil to a specific machine component. Although the main term can be defined broadly, the different types serve a more specific purpose. Constant level oilers, which can be abbreviated CLO, function by maintaining the optimum fluid level in a piece of equipment that naturally becomes depleted as a result of friction and wear caused by repeated use. As another example, chain oilers serve the specific purpose of applying oil to lubricate chains, which are a series of metal or plastic links used for movement in various types of equipment. Commonly referred to as grease pumps, grease dispensers serve the same purpose, just with a different lubricating material. Instead of liquid oil, grease dispensers apply grease, which is oil that has been thickened to a semi-solid state. A little lower on the public knowledge scale, air lubricators are unique in terms of operation and have been around for decades, although not well known outside of industry. Air lubricators utilize pneumatic power in order to apply lubrication; however, lubrication systems can also be powered by other means.

The two main ways in which lubrication systems are powered is by pneumatic and hydraulic power, although electric power can be used. Pneumatic power refers to the utilization of compressed air or other gases in order to provide energy and/or movement to various devices, while hydraulic power refers to the use of oil and other liquids such as water to transfer energy from one area to another through the application of force to the fluid. The way that lubrication systems generally work is that there is one main lubricant-pumping station that connects to several smaller lubricators, and is used to move the lubricants throughout the system and to the part requiring lubrication. The various lubricators are connected to the pumping station by means of fluid lines and valves that monitor the amount of lubricant being dispensed. While the pumping station is one of the most important components of the lubrication system, the other two main components are the lubricant reservoir and filter. A reservoir is an area, typically a small tank-like container, which stores lubricants that have returned from the area of lubrication. A lubricant filter, or lube filter, is important because it is used to remove abrasive contaminants that may have found their way within the lubricating system and could prove harmful to the lubricator itself and/or machinery being lubricated.

Images Provided by Oil-Rite® Corporation

---

Lubrication System Types

• Air lubricators provide proper lubrication and filtration to compressed air lines, which are used to power tools and other such machinery. These lubricators are often built into the line itself, providing constant lubrication.
  
• Automatic lubricators are systems that provide continuous or periodic anti-friction and fluid movement to machines and systems, which require lubricant to function properly.
  
• Beam lubricators work very much like chain lubricators but can be housed permanently onto the machine that needs lube for frequent use. They are usually set off on their own length of track or beam, which is not a part of the routine function of the system.
  
• Central lubrication systems consist of a conventional lever gun that supplies lubricant to a single grease fitting, which then feeds a number of grease distribution lines to lube points that are found throughout the machinery or system in need of lubricant.
  
• Circulating header systems have isolated lube zones in which the lube pump constantly runs and circulates oil through the header and back to the tank when in an idle period.
  
• Chain oilers are automatic units that travel the length of a chain or rail and disperse proper amounts of lubricant across the length of the system. 
• Constant level oilers are a type of lubrication equipment that serve to maintain a desired level of lubricant in a machine part or component.
• Dual-line systems have two main lines connected to a pump that use pressure to cause the pistons to dispense lubricant onto a designated area.
  
• Grease dispensers refer to a lubrication technology that provides petrol-based lubrication to machines and parts, which need them to function.
  
• Grease pumps lubricate machinery with grease.
• Intermittent systems are designed to supply lubricant periodically, based on a timer.
  
• Lubricating systems apply lubricant to machinery to prevent wear from friction.
• Lubrication equipment consists of various types of machinery used to provide proper lubrication to moving and rotating machine parts and components for reduced friction and enhanced productivity.
• Lubricators apply lubricant to moving mechanical parts.
• Microfog or oil mist lubrication systems deliver a mixture of atomized, micron oil particles and air to the area in need of lubricant. Sometimes, these systems are used for the cooling of bearings, as well as for fluid movement and cleaning.
  
• Oil dispenser is a container designed to hold and dispense oil for lubricating applications.
• Oilers are devices that apply lubricating oil to areas of friction in machinery.
• Orifice systems are single line systems in which the resistance to flow created by different size orifices proportions the flow to the lube points. These systems are not positive displacement and are limited to the use of oil as a lubricant.

---

Lubrication System Terms

Anhydrous - Devoid of water.

Ash - The amount of inorganic material in a lubricant, expressed as a percentage by weight.

Compounded Oil - Mineral oil to which has been added vegetable or animal oil or chemical lubricating oil additives to enhance certain physical or chemical properties of the finished blend.

Controller - Electrical device that includes a timer and a monitor.

Degradation - The failure of a machine or lubricant over time.

Divider Valve - A valve that measures positive displacement lubricant by dividing and proportioning input flow.

Dry Lubrication - A condition in which there is no lubrication between two moving parts.

Film Strength - Also referred to as "lubricity," it is an oil or grease's ability to lubricate.

Friction - The resistance to motion between two surfaces in contact. 

Injector - A positive displacement (oil or grease) lubricant measuring valve that dispenses lubricant when main line pressure rises and resets/primes when its compressed return spring forces the measuring piston back to its rest position at the point at which the main line pressure is vented.

Lube Cycle - The time period from one lubrication event to the start of the next.

Lube Fault - Incomplete or elongated lube cycle caused by a failure of the cycle switch or pressure switch.

Monitor - A device that checks the operation of a lubrication system against a designated time frame.

NLGI Number - A numerical scale for the classification of the consistency range of lubricating greases based on the ASTM penetration number. NLGI grades are in order of increasing consistency (hardness).

Oxidation - The process of combining a substance with oxygen; all petroleum products are subject to oxidation of some degree. The reaction increases with rise in temperature. 

Oxidation Stability - A lubricant's ability to resist reaction with oxygen.

Squeeze-Film Lubrication - The state of lubrication in which surfaces thickly coated or flooded with lubricant move toward each other at sufficient speeds to develop fluid pressure sufficient to support a load of short duration. 

Stroke Counter - The device that schedules the frequency of lubrication in a system.

Tribology - The science of the mechanisms of friction, lubrication and wear of interacting surfaces that are in relative motion.

Viscosity - The property of a fluid, semi-fluid or semi-solid substance that causes it to resist flow. Viscosity is defined as the shear stress on a fluid element divided by the rate of shear.

---

---