Lubrication Numbers

For industrial gears and circulating oils there is a specification published by the American Gear Manufacturers Association, which expresses the viscosities corresponding to the AGMA Lubricant Numbers in Saybolt Universal Seconds only. The approximate viscosities in centistokes are provided in Table 52.4 for convenience. The recommendations in Tables 52.5 and 52.6 are intended as a guide for lubricant selection. 

Table 52.5 Lubrication of industrial enclosed gear drives. AGMA Lubricant Number recommendations for helical, herringbone, straight bevel, spiral bevel and spur ...

Figure 9. Effect of BHBM-B and DBTM, alone and in combination on the formation of unsaturation in PVC during oven aging at 140 C. All formulations contain lubricants. Numbers on curves are concentrations (10 mol/100 g). T290 is a stabilizer containing...

Viscosities of AGMA lubricant number 13 and above are specified at 100°C (210°F) as measurement of viscosities of these heavy lubricants at 40°C (100 F) would not be practical. 

Lubricant number Structure of lubricant Friction coefficient Melting point /°C... 

This is an analysis frequently conducted on oil lubricants. Generally, the additive is known and its concentration can be followed by direct comparison of the oil with additive and the base stock. For example, concentrations of a few ppm of dithiophosphates or phenols are obtained with an interferometer. However, additive oils today contain a large number of products their identification or their analysis by IR spectrometry most often requires preliminary separation, either by dialysis or by liquid phase chromatography. 

The great number of possible associations between the types of liquid lubricants and gelling agents results in many different categories of greases ... 

Owing to the large number of types of industrial lubricants, the number of constraints, and therefore the number of desired properties, is very large. The main industrial oils are summarized in Tables 6.4 and 6.5, the first giving the constraints common to all applications, and the second addressing the more specific requirements. A few essential properties appear from these tables ... 

The VI is a number that results from a calculation involving the viscosities at 40°C and 100°C. It characterizes the capacity of the lubricant to maintain a constant viscosity through a large range in temperature. This property can be improved by additives. 

Glavincevski, B., O.L. Gulder and L. Gardner (1984), Cetane number estimation of diesel fuels from carbon type structural composition . SAE paper No. S4- 34, International fuels and lubricants meeting, Baltimore, MD. 

The products could be classified as a function of various criteria physical properties (in particular, volatility), the way they are created (primary distillation or conversion). Nevertheless, the classification most relevant to this discussion is linked to the end product use LPG, premium gasoline, kerosene and diesel oil, medium and heavy fuels, specialty products like solvents, lubricants, and asphalts. Indeed, the product specifications are generally related to the end use. Traditionally, they have to do with specific properties octane number for premium gasoline, cetane number for diesel oil as well as overall physical properties such as density, distillation curves and viscosity. 

A considerable number of experimental extensions have been developed in recent years. Luckliam et al [5] and Dan [ ] review examples of dynamic measurements in the SFA. Studying the visco-elastic response of surfactant films [ ] or adsorbed polymers [7, 9] promises to yield new insights into molecular mechanisms of frictional energy loss in boundary-lubricated systems [28, 70]. 

Lubricants, Fuels, and Petroleum. The adipate and azelate diesters of through alcohols, as weU as those of tridecyl alcohol, are used as synthetic lubricants, hydrauHc fluids, and brake fluids. Phosphate esters are utilized as industrial and aviation functional fluids and to a smaH extent as additives in other lubricants. A number of alcohols, particularly the Cg materials, are employed to produce zinc dialkyldithiophosphates as lubricant antiwear additives. A smaH amount is used to make viscosity index improvers for lubricating oils. 2-Ethylhexyl nitrate [24247-96-7] serves as a cetane improver for diesel fuels and hexanol is used as an additive to fuel oil or other fuels (57). Various enhanced oil recovery processes utilize formulations containing hexanol or heptanol to displace oil from underground reservoirs (58) the alcohols and derivatives are also used as defoamers in oil production. 

A number of chemical products are derived from Sasol s synthetic fuel operations based on the Fischer-Tropsch synthesis including paraffin waxes from the Arge process and several polar and nonpolar hydrocarbon mixtures from the Synthol process. Products suitable for use as hot melt adhesives, PVC lubricants, cormgated cardboard coating emulsions, and poHshes have been developed from Arge waxes. Wax blends containing medium and hard wax fractions are useful for making candles, and over 20,000 t/yr of wax are sold for this appHcation. 

The products manufactured are predominantiy paraffinic, free from sulfur, nitrogen, and other impurities, and have excellent combustion properties. The very high cetane number and smoke point indicate clean-burning hydrocarbon Hquids having reduced harmful exhaust emissions. SMDS has also been proposed to produce chemical intermediates, paraffinic solvents, and extra high viscosity index (XHVI) lubeoils (see Lubrication and lubricants) (44). 

Some U.S. governmental lubricant requirements for nontactical equipment is now acquired as Commercial Item Descriptions (CID), rather than against specific military numbers. A new classification system for shear-stable, high VI hydraulic fluids was balloted by ASTM in 1994. 

Petroleum. Apart from its use ia petrochemicals manufacture, there are a number of small, scattered uses of lime ia petroleum (qv) production. These are ia making red lime (drilling) muds, calcium-based lubricating grease, neutralization of organic sulfur compounds and waste acid effluents, water treatment ia water flooding (secondary oil recovery), and use of lime and pozzolans for cementing very deep oil wells. 

Poly(alkylene glycol)s have a number of characteristics that make them desirable as lubricants. Compared to petroleum lubricants, they have lower pour points, a higher viscosity index, and a wider range of solubilities including water, compatibility with elastomers, less tendency to form tar and sludge, and lower vapor pressure (35). 

Substrate Properties. It is clear from equation 5 that higher hardness of the substrate lowers friction. Wear rate of the film also is generally lower. Phosphate undercoats on steel considerably improve wear life of bonded coatings by providing a porous surface which holds reserve lubricant. The same is tme for surfaces that are vapor- or sandblasted prior to appHcation of the soHd-film lubricant. A number of typical surface pretreatments are given in Table 13 to prepare a surface for solid-film bonding (61). 

Upon satisfactory deterrnination of nontoxicity of a lubricant, the USDA issues one of two ratings HI for use where there is incidental or possible food contact as by splashing or dripping from machinery above an edible product, or H2 for no food contact as in sealed gear boxes or machinery below a product line (82—84). These classes include a number of petroleum and synthetic oils and greases. 

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