Lubricant crankcase

OILS, MISCELLANEOUS LUBRICATING Crankcase oil, Motor oil, Transmission oil NL 0 1 0 ... 

Diisodecyl azelate Petroleum distillates, heavy hydrotreated naphthenic Petroleum distillates, light naphthenic, solvent-refined Tri-2-ethylhexyl pyromellitate basestock, lubricant crankcase/compressor oils... 

Trimethylolpropane trioctanoate Trioctanoin Triolein Tripalmitin lubricant, crankcase Dioctyl dimer dilinoleate lubricant, crankcase oils Antimony dialkylphosphorodithioate lubricant, crayons... 

Detergents are metal salts of organic acids used primarily in crankcase lubricants. Alkylbenzenesulfonic acids, alkylphenols, sulfur- and methjiene-coupled alkyl phenols, carboxyUc acids, and alkylphosphonic acids are commonly used as their calcium, sodium, and magnesium salts. Calcium sulfonates, overbased with excess calcium hydroxide or calcium carbonate to neutralize acidic combustion and oxidation products, constitute 65% of the total detergent market. These are followed by calcium phenates at 31% (22). 

The molecular dipstick microscope is related to the AFM. It measures lubricant film thickness. The probe is lowered into the oil film on a surface (like the automobile engine crankcase dipstick). The tip is attracted to the surface by the surface tension of the film but repelled by van der Waal s forces from the hard substrate. By noting the height of the probe from the two surfaces as it makes contact, the film thickness can be measured with a precision of about 0.5 nm. 

A sequence of tests has been devised to evaluate antioxidants for use in automotive crankcase lubricants. The Indiana Stirring Oxidation Test (ISOT) JISK2514 is an example of a laboratory screening test. The oil is stirred at 165.5°C in the presence of air. Copper and iron strips are used as metal catalysts. The development of sludge, viscosity, and acidity are deterrnined periodically. Failure time is determined when the development of acidity requires... 

Lubricated cylinders use a separate mechanical lubricator to force feed, in metered droplet form, a very precise amount of lubricant to specified points. This minimizes the amount of lubricant in the cylinder and allows a lubricant most compatible with the gas to be selected without compromising the frame lubrication system. Lubricant is fed to a point or points on the cylinder to service the piston rings and the packing when required. In a few cases, as in air compressors, the packing is lubricated from the crankcase. On some applications involving wet CO7 or H2S m the gas stream, special materials may be avoided if one of the lubrication points IS connected to the suction pulsation dampener. 

Chapter 3, which discussed various reciprocating compressors, stated that riiaii> reciprocators use a pressure-fed lubrication system for the frame bearings. This system is built into the crankcase in many applica tions. I he basics of these systems follow the fundamental criteria which will lie discussed with the fully separate system. The larger reciprocating compressors may use a separate frame lubrication system. 

Chemical Designations - Synonyms Crankcase oil Lubricating oil Transmission oil Chemical Formula Not applicable. 

If the crankcase compression illustrated in Figure 5 is used, the reservoir of lubricating oil normally contained in the crankcase of a four-stroke engine (sec Figure 1) must be eliminated. Cylinder lubrication is then usually accomplished by mixing a small quantity of oil into the fuel. This increases oil consumption. An alternative allowing use of the... 

A pressurized lubrication system using an engine-mounted pump is the choice of most manufacturers. A sump in the crankcase or an external drain tank together with filters and coolers complete the system. The choice of oil should be consistent with the manufacturer s recommendation, and should only be varied if the engine is to be operated in unusual or extreme conditions. 

The flash point of an oil is the temperature at which it gives off, under specified conditions, sufficient vapor to form a flammable mixture with air. This is very different from the temperature of spontaneous combustion. The test is an empirical one and the result depends upon the instm-ment used and the prescribed conditions. For example, the flash point may be closed or open , depending on whether the test apparatus has a lid or not. As far as lubricating oils are concerned, the test is of limited significance, although it can be indicative of contamination (for example, the dilution of crankcase oil by fuel). 

Comite des Constructeurs d Automobiles du Marche Commun represents joint industry opinion on factors such as lubricant specifications, emissions, vehicle design and safety standards. With regard to crankcase lubricants, CCMC defines sequences of engine tests, and the tests themselves are defined by CEC (Coordinating European Committee for the Development of Performance Tests for Lubricants and Engine Euels a joint body of the oil and motor industries). 

In piston-type compressors, the oil serves three functions in addition to the main one of lubricating the bearings and cylinders. It helps to seal the fine clearances around piston rings, piston rods and valves, and thus minimizes blow-by of air (which reduces efficiency and can cause overheating). It contributes to cooling by dissipating heat to the walls of the crankcase and it prevents corrosion that would otherwise be caused by moisture condensing from the compressed air. 

In a crankcase-lubricated engine, the oil compartment acts as a sink for heavy molecular incomplete combustion products such as PAH, which can be present at up to 1000 times original concentrations. The lubricating oil is altered by nitration, cracking of polymers,... 

Uses. Used mineral-hased crankcase oil is mixed with other oils to produce cutting oils or other lubricating oils. It is incinerated for energy in oil burners in homes, industrial steam boilers, municipal incinerators, and rotary cement kilns. It is also used in asphalt production. 

As a result of this, unbumed fuel can remain in the combustion chamber to be drawn into the crankcase with the oil lubricating the piston cylinder, or it can remain within the upper part of the cylinder to carbonize and form combustion chamber deposits. Piston ring and land groove deposits can also form. 

Crankcase Dilution Dilution of lubricating oil in the oil pan or sump of an engine by fuel which has entered the crankcase. 

Before 1925, there were a few compounded oils made for special purposes, such as lubrication of marine engines and steam cylinders, but additives were not used in automotive crankcase oils. In the 1930 s, chemical compounds made by condensation of chlorinated paraffin wax with naphthalene were found to lower the pour points of oils. Pour depressants (9) apparently are adsorbed on small wax crystals which separate from oils when they are chilled. The protective adsorbed layer of additive prevents the normal interlacing of larger wax crystals which forms a gel. In 1934 polymerized unsaturated hydrocarbons first came into large scale commercial use to lower the temperature coefficient of viscosity of oils. Other compounds for increasing the viscosity index of oils have since become common. 

All hydrocarbon oils react with oxygen upon exposure to air at sufficiently elevated temperatures for long periods of time. Over the range of temperatures developed in engine crankcase, the rate of oil oxidation has been found to double for every 20°F rise in temperature. Although all lubricating oil hydrocarbons are susceptible to oxidation, of more importance to engine performance are the oxidation products. Paraffinic hydrocarbons... 

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