Protective lubricant oils

Polyisobutylene has the chemical properties of a saturated hydrocarbon. The unsaturated end groups undergo reactions typical of a hindered olefin and are used, particularly in the case of low mol wt materials, as a route to modification eg, the introduction of amine groups to produce dispersants for lubricating oils. The in-chain unsaturation in butyl mbber is attacked by atmospheric ozone, and unless protected can lead to cracking of strained vulcanizates. Oxidative degradation, which leads to chain cleavage, is slow, and the polymers are protected by antioxidants (75). 

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. 

The main function of most lubricants is to reduce friction and wear between moving surfaces and to abstract heat. They also have to remove debris from the contact area, e.g. combustion products in an engine cylinder, swarf in metal-cutting operations. Sometimes they have to protect the lubricated or adjacent parts against corrosion, but this is not a prime function of most lubricants. On the other hand, many lubricants do contain corrosion inhibitors and some lubricating oils, greases, mineral fluids and compounds are specially formulated to prevent the corrosion of machinery or machine parts, particularly when these components are in storage or transit. These temporary protectives are described in Section 17.3. 

Vacuum distillates or residual fraction of vacuum distillates are the main source of lubricating oils from the petroleum industry. Although they account for only 1% of the volume of petroleum fuel sales they are a high value unit. Besides lubrication they are used as heat transfer mediums, hydraulic fluids, corrosion protection, etc., both in industry and society. 

From a fire protection perspective, the primary issues are the gas or vapor handled, their size, operating temperature and pressure, auxiliary systems (lubricating oil), and value or importance to the process they serve. 

Corrosion of ammunition, weapons other items of ordnance is prevented by some type of treatment (such as painting, plating or other surface treatment) of many components, in addn to proper packing sealing to protect the components. The usual rust preventative lubricating oil preservative compds are not used on ammo components because they might prevent proper functioning, and also because ammo components contain many inaccesible cavities from which these materials cannot easily be removed (Ref 12a)... 

The ability of lubricating oil to reduce wear and prevent damage of interacting solids is the crucial factor controlling lubricant formulations. Chemical reactions of lubricant components, especially of so-called antiwear and extreme-pressure additives, occur during friction. These reactions involve the formation of a film on the contact surface. The film alters the surface s character and thus protects it. 

Additive interactions take place in lubricating oil formulation and at surfaces (Kajdas, 2001 Spikes, 1989). At surfaces, additive interactions should protect metallic engine surfaces from corrosion, prevent rusting, build-up of varnishes, agglomeration of particles, and form low friction and protective films. In the base... 

Table 2.7. Performance of synthetic and mineral lubricant oils. Relative evaluation of viscosity, stability (thermal, oxidation, hydrolytic, volatility), lubricity (wear protection and fatigue) and environmental impact...

Synthetic oils By using Table 2.7, Performance of synthetic and mineral lubricant oils , consider the benefits of using synthetic engine oils in several main aspects of (a) engine wear protection, (b) improved fuel and oil economy and (c) environmental protection. Which of the synthetic oils phosphate esters or alkylated aromatics (PAO) are the most common synthetic fluids used in automotive motor oils today ... 

The oil analyses have shown that the TBN values of lubricating oils deplete completely while at the same time, the corrosion rate can be considerably reduced. The relationship between the solubilization of large quantities of acid, total base number (TBN), and total acid number (TAN) values with the rate of corrosion is still unresolved. TAN values are not a good prediction of corrosion, and the source of extra TBN is much more important in the neutralization of corrosive acids than the simple numerical value of TBN. The effect of hard-core RMs shows poor correlation between used oil sample TAN values and the potential for bearing corrosion (Denison, 1944 Kreuz, 1970). Where corrosion rates are reduced by treatment with hard-core reverse micelle detergent, and no significant reduction in TAN has occurred, corrosion protection must have occurred by a... 

Polyisobutylenes are easily made via the acid-catalyzed polymerization of isobutylene. The low molecular weight polymers are used as additives for gasoline and lubricating oils, whereas higher molecular weight polymers are used as adhesives, sealants, caulks, and protective insulation. 

Production of sulfides. This may involve the production of FeS, Fe (OH)2 etc. and an aggressive chemical agent such as hydrogen sulfide (H2S) or acidity. Micro-organisms may also consume chemical species that are important in corrosion reactions (e.g., oxygen or nitrite inhibitors). Alternatively, their physical presence may form a slime or poultice, which leads to differential aeration cell attack or crevice corrosion. They may also break down the desirable physical properties of lubricating oils or protective coatings. (Stott)5... 

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