Lubricants deterioration

Lubricant deterioration See Fig. 6.1 for the mechanism of the oil deterioration. Explain the difference in concept of some indicators viscosity, TBN, TAN, insolubles. 

The next chapter is a review of current practice in lubrication of internal combustion engines and lubricant design. The role of individual lubricant components and their use in mineral and synthetic formulations is covered. This is followed by a discussion of the tribochemical effects of additive interactions. The heart of the manuscript is chapters, "Tribochemical nature of antiwear film , "Surface tribochemistry and activated processes", and "Analytical techniques in lubricating practices". Topics covered include tribofilm formation, organomolybdenum compounds in surface protection, catalytic activity of rubbing surfaces, introduction of some techniques for evaluation of tribofilms composition and analytical techniques for evaluation of lubricant degradation. Examples of the application of basic concepts are introduced, eg., acidity and basicity in the process of lubricant deterioration. 

TA Thermal analysis Thermal energy Heat dissipation Microscopic surface structure Adsorption energy, lubricant deterioration, etc. Transition cell structure, reaction products, etc. 

Saloka GS, Meitzler AH (1991) A capacitive lubricant deterioration sensor. SAE paper 910497, proceedings of SAE international congress, Detroit, 25 Feb - March 1, pp 137-146... 

Rolling element bearings also need a lubricant to meet or exceed their rated life. In the absence of high temperatures, however, excellent performance can be obtained with a very small quantity of lubricant. Excess lubricant causes excessive heating, which accelerates lubricant deterioration. 

Overheated pump motor at right caused by lubricant deterioration 86... 

Determine the type of compressor lubricant used before selecting a filter. Some filter components such as gaskets, seals and transparent bowls are not compatible with certain synthetic compressor lubricants. Deterioration of these parts as a result of contact with such lubricants may cause the filters to burst and even end in personal injury. Ensure that the manufacturer s pressure rating and flow capacity of the filter are equal to or exeeed the pressure and flow at the point of use. 

In important process pumps, the grease in a bearing should be changed every 12 to 18 months. This will a,ssure a reliable pump operation and service because time alone causes certain deterioration in the lubricating ability of grea.se. 

The turboexpander dry gas seal consists of the conventional dry gas seal mating ring and primary ring, an outboard labyrinth, an inboard labyrinth, and tlie cavity to be vented, if desired. Tlie outboard labyrinth reduces warm seal gas leakage to the process side efficiency deterioration is thus minimized. The inboard labyrinth, on one hand, provides an additional seal between the process and lubricating fluids. On the other hand, it allows injection of an inert gas, if desired. In the latter case, inert gas leaks to the bearing side and to the cavity between the... 

The discharge temperature should be limited to 300°F as recommended by API 618. Higher temperatures cause problems with lubricant coking and valve deterioration. In nonlube service, the ring material is also a factor in setting the temperature limit. While 300°F doesn t seem all that hot, it should be remembered that this is an average outlet temperature, whereas the cylinder will have hot spots exceeding this temperature. 

Condition monitoring is an established technique which has been used by capital-intensive or high-risk industries to protect their investment. The concept has developed radically in recent years largely due to advances in computerization, which offer greater scope for sophisticated techniques. These fall into three types of monitoring vibration, performance and wear debris. The last monitors particulate debris in a fluid such as lubricating oil, caused by the deterioration of a component. 

A lubricant-starved chain drive shows a brownish or rusty coloration around the joints and in the roller-bushing areas when the link is disassembled and the pin inspected. The normal highly polished surface of the pin will have deteriorated to a roughened, grooved, or galled surface that can eventually destroy the hardened surfaces of the chain parts and increase wear until the drive is completely destroyed. This also will be hue if a lubricant that does not meet the chain s technical specifications is used. 

In the pyrot area, paraffin is widely used in the manuf of book and wooden matches, as a protective coating to counteract possible surface deterioration of metal powders, as a lubricant and waterproofing agent for the interior surfaces of kraft paper flare and signal cases, and as a binder which tends to fill interstices between particles on press loading (Ref 7, pp 69, 71, 302 316)... 

Flavoring agents proper are commonly volatile oils that have been dissolved in alcohol and sprayed onto the dried granules or have simply been adsorbed onto another excipient (e.g., talc). They are added immediately prior to compression to avoid loss through volatilization. In some cases they may even have some lubricating activity. If the oil normally contains ter-penes, a low terpene grade is better so as to avoid possible deterioration in taste due to terpene oxidation... 

A third set of samples was constructed from Al-Tl. As observed using other metallic adherends, little difference in joint strength was observed over a period of 60 days between samples in which the substrates had been alkaline cleaned, lubricated or left untreated. (Figure 7). In addition, the most rapid deterioration in bond strength occurred in environments where high concentrations of chloride ions were present, as depicted by salt fog and cycle test data. 

The unusual properties of silicones make them useful for some special applications as lubricants (20). They are relatively resistant to deterioration by heat or oxidation, and have the desirable properties of high viscosity index, low pour point, and low volatility. They may promote wear in steel-to-steel bearing surfaces under conditions of sliding friction, and are not generally useful for such applications. Silicones are satisfactory lubricants in antifriction bearings and in some bearing combinations other than steel sliding on steel. 

ANTIOXIDANTS. Usually an organic compound added to various types of materials, such as rubber, natural fats and oils, food products, gasoline, and lubricating oils, for the purposes of retarding oxidation and associated deterioration, rancidity, gum formation, reduction in shelf life, etc. 

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