Synthetic lubricants applications

Lubrication of compressor cylinders can be tailored to the application. The cylinders may be designed for normal hydrocarbon lubricants or can be modified for synthetic lubricants. The cylinder may also be designed for self lubrication, generally referred to as nonlubed. A compromise lubrication method that uses the nonlubed design but requires a small amount of lubricant is referred to as the mini-lube system. 

Metalworking fluids contain mineral oils (refer to p. 80) or synthetic lubricants they are used neat or in admixture with water. They may contain small amounts of biocides, stabilizers, emulsifiers, coiTosion inhibitors, fragrances and extreme pressure additives. The formulations render them suitable for application to metal being worked, generally from a recirculatory system, to provide lubrication, corrosion protection, swarf removal and cooling of the tool and machined surface. 

The recommendations of the International Standards Organization (ISO) covering mineral-oil lubricants for reciprocating compressors are set out in ISO DP 6521, under the ISO-L-DAA and ISO-L-DAB classifications. These cover applications wherever air-discharge temperature are, respectively, below and above 160°C (329°F). For mineral-oil lubricants used in oil-flooded rotary-screw compressors the classifications ISO-L-DAG and DAH cover applications where temperatures are, respectively, below 100°C (212°F) and in the 100-110°C range. For more severe applications, where synthetic lubricants might be used, the ISO-L-DAC and DAJ specifications cover both reciprocating and oil-flooded rotary-screw requirements. 

Marino MP, Placek DG. 1994. Phosphate Esters. In CRC Handbook of Lubrication and Tribology Volume III Monitoring, Materials, Synthetic Lubricants, and Applications, ed. E. Richard Booser. Boca Raton CRC Press, Inc. 269-286. 

Today, glycerol has over 2000 different applications, in cosmetics, pharmaceutics, foods and drinks, tobacco, paper, inks and printing colors, the production of phthalic and maleic alkyd resins and crosslinked polyesters, and as a hydraulic agent. Polyglycerols have a wide range of applications as emulsifiers, and technical esters of glycerol with fatty acids are used as synthetic lubricants [4]. 

By 2000, the alpha olefin market had grown to more than 3. billion pounds. Technology had brought down the cost of producing them and simultaneously, a broad range of applications for all the alpha olefins expanded rapidly—surfactants, synthetic lubricants, plasticizer alcohols, fatty acids, mercaptans, comonomers, biocides, paper and textile sizing, oil field chemicals, lube oil., additives, plastic processing aids, and cosmetics. 

The variety of alpha olefin application is extensive, including polymers, surfactants, synthetic lubricants, lube oil additives, plasticizer alcohols, mer-captans, and fatty acids. 

Synthetic lubricants are made with neopentyl glycol in the base-stock polyester (24). Excellent thermal stability and viscosity control are imparted to special high performance aviation lubricants by the inclusion of polyester thickening agents made from neopentyl glycol (25,26) (see Lubrication AND lubricants). Neopentyl glycol is also used to manufacture polymeric plasticizers that exhibit the improved thermal, hydrolytic, and uv stability necessary for use in some exterior applications (27). 

Polypheny I Ethers. Both alkyl-substituted and iinsubxtiinlcd polypheny ethers are included in this class of synthetic lubricants. General preparation involves the (.llhiian ether synthesis. The unsubstituted polyphenyl ethers have outstanding thermal, oxidative and radiation resistance, however, poor low-temperature characteristics arc a major drawback. Alkyl substitution improves low-temperature viscosity, but detracts from stability. Most lubricant uses are developmental in nature and involve aircrali and aerospace applications. 

Some applications of the synthetic fluids are motor oil, trucks, marine diesel, transmissions and industrial lubricants, aviation and aerospace lubricants, fire-resistant fluids, and greases. Specifications for several military lubricants can be met only by a synthetic product. All commercial and military jet aircraft engines use synthetic lubricants, in addition to the space shuttle, NASA, and nuclear submarines. 

Applications. Table 2.9 summarizes the possibilities of synthetic lubricants, by listing information on the main applications of some of the most important fluids (Bartz, 1999 Miller, 1993 Rudnick and Shubkin, 1999). 

The application of branched-chain alcohol diesters in part-synthetic lubricants is covered as one of the ways the petroleum industry is responding to the challenges brought on by the trend toward new smaller cars with more demanding lubricant requirements. 

Adipic acid is mainly used to produce nylon-6,6, a synthetic polyamide used in clothing, in the automobile industry, and in construction it also finds application in polyurethanes, plasticizers, and synthetic lubricants. Manufacture of nylon accounts for 89% of adipic acid consumption in North America, and 55-65% in Western Europe and Japan. 

It is not sufficient merely to have such material on the libraiy shelves it must also be carefully indexed. All new books and pamphlets received are examined carefully for information that would not ordinarily be expected in such publications. In The Chemistry of the Non-Benzenoid Hydrocarbons (1922) by B. T. Brooks, for example, there are references to naphthenic acids, production of fatty acids by wax oxidation, and synthetic lubricating oils. In Volume VI of Colloid Chemistry (1946) edited by Jerome Alexander, there are chapters on the Geiger-Miiller x-ray spectrometer, electron microscopy, catalysis and its industrial applications, soil stabilization, polythene, and potential nuclear energy. Such information is typed on 3 X 5 cards on some books as many as forty or fifty cards may be required. In this way an extremely useful file of information has been built up that might otherwise be overlooked as valuable data sometimes appear in unexpected places. 

Abstract The chemical nature and technology of the main synthetic lubricant base fluids is described, covering polyalphaolefins, alkylated aromatics, gas-to-liquid (GTL) base fluids, polybutenes, aliphatic diesters, polyolesters, polyalkylene glycols or PAGs and phosphate esters. Other synthetic lubricant base oils such as the silicones, borate esters, perfluoroethers and polyphenylene ethers are considered to have restricted applications due to either high cost or performance limitations and are not considered here. Each of the main synthetic base fluids is described for their chemical and physical properties, manufacture and production, their chemistry, key properties, applications and their implications when used in the environment. 

Other important synthetic lubricant materials are the silicones, borate esters, per-fluoroethers and polyphenylene ethers but these have restricted applications due either to high cost or to performance limitations and are not considered here. The recent development of pure hydrocarbon base fluids derived from gas-to-liquid, GTL, technology is also included in this chapter. 

The wide temperature performance range for PAO-based lubricants together with their excellent physical, chemical and thermo-oxidative stabilities has increased the use of PAOs in a wide variety of applications. Traditional application areas such as aerospace, transmissions and hydraulic systems continue to require the lubricant performance benefits of PAOs. In addition, the stresses of both increased performance and longer lifetimes placed on automotive and marine lubricants have increased growth in the use of PAO-based synthetic lubricants in these applications. 

I vo-stroke engine lubrication Synthetic lubricants virtually eliminate engine problems associated with deposition and fouling, commonly seen with mineral oil lubricants. Although esters are predominant in this application, PAGs tend to have special uses, for example, with model engines where a mixture of PAG/methanol provides a cleaner alternative to castor oil-based fuels. 

No moving parts are involved in the combustion process of gas turbines therefore, the turbines make little demand on the lubricant and present few lubrication problems. Gas turbines for industrial applications have evolved from steam turbine practice, thus they are similar in design and lubrication requirements except that operating temperatures are much higher. Accordingly, steam turbine lubricants can often be used in industrial gas turbine lubrication but for particularly high temperatures, synthetic lubricants are required. 

Synthetic lubricants are starting to find limited specialised applications and trunk piston engine oils of 12 and 30 base number (BN) are available. They are currently based on polyalphaolefins with the inclusion of esters to improve additive solubility and seal compatibility. 

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