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37 items found. For further information on glossary terms contact us
Coked material remaining after an oil has been subjected to high temperatures.
A cancer-causing substance. Certain petroleum products are classified as potential carcinogens under OSHA criteria. Suppliers are required to identify such products as potential carcinogens on package labels and Material Safety Data Sheets.
The formation of an air or vapour pocket (or bubble) due to lowering of pressure in a liquid, often as a result of a solid body, such as a piston, moving through the liquid; also, the pitting or wearing away of a solid surface as a result of the collapse of a vapour bubble. Cavitation can occur in a hydraulic system as a result of low fluid levels that draw air into the system, producing tiny bubbles that expand explosively at the pump outlet, causing metal erosion and eventual pump destruction. Cavitation can also result when reduced pressure in lubricating grease dispensing systems forms a void, or cavity, which impedes suction and prevents the flow of greases.
Cold Crank Simulator
Coordinating European Council. An Industry-based organisation which develops test methods for the performance testing of Automotive Engine Oil, Fuels & Transmission Fluids.
Unit of measure for apparent viscosity.
Unit of measure for Kinematic Viscosity.
A value calculated from the physical properties of a diesel fuel to predict its Cetane Number.
Measure of ignition quality of a diesel fuel. The higher the Cetane Number, the easier a high-speed, direct injection engine will start, and the less white smoking and diesel knock after start up.
Cetane Number Improver
An additive that boosts the Cetane Number of a fuel while improving combustion efficiency and increasing power in a diesel engine.
The tendency of a substance or mixture to resist chemical change.
Cleveland Open Cup (C.O.C.)
An apparatus used to determine the flash and fire points of petroleum products other than fuel oils and those having an open cup flash below 79C/175F.
Closed Cup (covered sample container)
D93 "Flash Point by Pensky-Martens Closed Test" for fuel oils — also for cutback asphalts and other viscous materials and suspensions of solids
The temperature at which a cloud of wax crystals appears when a lubricant or distillate fuel is cooled under standard conditions. Indicates the tendency of the material to plug filters or small orifices under cold weather conditions.
Chemical Manufacturers Association
Coefficient of Friction
Number obtained by dividing the frictional force resisting motion between two bodies (F) by the normal force pressing the bodies together (L). m = F L
That property of a substance that causes it to resist being pulled apart by mechanical means.
Cold Cranking Simulator (C.C.S.) developed in a cold engine.
An intermediate shear rate viscometer that predicts the ability of an oil to permit a satisfactory cranking speed to be developed in a cold engine.
The space between the piston and cylinder head in an internal combustion engine where the charge of fuel plus air is burned to produce power.
A lubricants ability to be mixed with another lubricant without detriment to either lubricant. Also, the ability to come into contact with other components or materials without detrimental effects.
Substance formed by the combination of two or more elements with differing physical and chemical properties than the combining elements.
A blend of petroleum oil with small amounts of fatty or synthetic fatty oils is referred to as compounding. Compounded oils are used for certain wet applications to prevent washing-off of the lubricant from the metal surfaces. The fatty materials enable the oil to combine physically with the water instead of being displaced by it. Cylinder oils for wet steam applications and for some air compressors are compounded. Because the fatty material imparts a strong affinity for metal surfaces, compounded oils are frequently used for applications in which lubricity or extra load-carrying ability are needed. They are not generally recommended, however, for service that requires high oxidation stability. (See Boundary Lubrication)
Ignition of fuel by the heat generated in compressing the air charge, as in the diesel engine.
The ratio of the volume of combustion space at the bottom dead centre to that at top dead centre, in an internal combustion engine.
The degree to which a semi-solid material such as grease resists deformation.
Any material that is unwanted or adversely affects the fluid power system and/or its components.
Fluid used to remove heat. Commonly found in an engines cooling system.
Copper Strip Corrosion
Qualitative measure of the tendency of a liquid to corrode pure copper.
Destruction of a metal by chemical or electro-chemical reaction with its environment.
A lubricant additive for protecting surfaces against chemical attack from contaminants in the lubricant. The most common types of corrosion inhibitors generally react chemically with the metal surfaces to be protected, thus forming an inert film in these areas.
Refining process in which large molecules are broken down into smaller molecules. Cracking takes place to some extent whenever high molecular material is heated strongly, but can be increased by catalysts.
The housing in which the crankshaft and many other parts of the engine operate. On a two-cycle engine, the area in which the fuel/oil mixture is drawn before being transferred to the cylinder.
When unburned fuel finds its way past the piston rings into the crankcase oil, where it dilutes or thins out the engine lubricating oil.
Naturally occurring petroleum, before any refining or treatment.
A lubricant for independently lubricated cylinders, such as those of steam engines and air compressors; also for lubrication of valves and other elements in the cylinder area. Steam cylinder oils are available in a range of grades with high viscosity’s to compensate for the thinning effect of high temperatures; of these, the heavier grades are formulated for superheated and high-pressure steam, and the lighter grades for wet, saturated, or low-pressure steam. Some grades are compounded for service in excessive moisture; see compounded oil. Cylinder oils lubricate on a once-through basis.
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Terms related to the chemistry of lubricants
Listing of engine parts and devices
View terms related to engine performance
Terms related to oil and lubricant parameters
Terms related to processes
Types of oils, lubricants and greases
Terms related to lubricant properties
Listing of various industry trade associations
Test methods used to measure lubricant properties
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Millers Oils Ltd
Brighouse, West Yorkshire
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