Specifications lubrication and

Table 16.7 is an example of viscosity limits for a medium speed diesel engine selected from the culled sample population in Fig. 16.22. These limits will reliably indicate fuel dilution and oil oxidation problems for the specific lubricant and fuel used. 

For all new applications, a competent bearing or lubrication engineer should be consulted to recommend the specific lubricant and method of lubrication for the specific bearing s operating and ambient conditions. 

Annealed tantalum, like copper, lead, stainless steel, and some other metals, is sticky. Therefore, it has a strong tendency to seize, tear, and gall. To avoid this, specific lubricant and die material combinations are required in high-pressure forming operations. 

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. 

Ethylene. Under the influence of pressure and a catalyst, ethylene yields a white, tough but flexible waxy sohd, known as Polythene. Polyethylene possesses excellent electric insulation properties and high water resistance it has a low specific gravity and a low softening point (about 110°). The chemical inertness oi Polythene has found application in the manufacture of many items of apparatus for the laboratory. It is a useful lubricant for ground glass connexions, particularly at relatively high temperatures. 

One hquid in this class intended for aircraft engine use is described in military specification MIL-L-87100 for operation from +15 to 300°C. Limitations of this class of synthetics are pour points of +5°C and higher, relatively poor lubricity, and high cost of 265/L ( 1000 + /gal) (44). Polyphenyl ether greases are available with good radiation resistance for appHcations in the temperature range of +5 to 288°C. 

Natural Ethoxylated Fats, Oils, and Waxes. Castor oil (qv) is a triglyceride high in ticinoleic esters. Ethoxylation in the presence of an alkaline catalyst to a polyoxyethylene content of 60—70 wt % yields water-soluble surfactants (Table 20). Because alkaline catalysts also effect transestenfication, ethoxylated castor oil surfactants are complex mixtures with components resulting from transesterrfication and subsequent ethoxylation at the available hydroxyl groups. The ethoxylates are pale amber Hquids of specific gravity just above 1.0 at room temperature. They are hydrophilic emulsifiers, dispersants, lubricants, and solubilizers used as textile additives and finishing agents, as well as in paper (qv) and leather (qv) manufacture. 

In selec ting the machines of choice, the use of specific speed and diameter best describe the flow. Figure 10-67 shows the characteristics of the three types of compressors. Other considerations in chemical plant service such as problems with gases which may be corrosive or have abrasive solids in suspension must be dealt with. Gases at elevated temperatures may create a potential explosion hazard, while air at the same temperatures may be handled qmte normally minute amounts of lubricating oil or water may contaminate the process gas and so may not be permissible, and for continuous-process use, a high degree of equipment rehability is required, since frequent shutdowns for inspec tion or maintenance cannot be tolerated. 

The lubrication system for the turbine is designed to provide both lubrication and cooling. It is not unusual that in the case of many gas turbines the maximum temperatures reached in the bearing section is about 10-15 minutes after the unit has been shutdown. This means that the lubrication system should continue to operate for a minimum of 20 minutes after the turbine has been shutdown. This system closely follows the outline in API Standard 614, which is discussed in detail in Chapter 15. Separate lubrication systems for various sections of the turbine and driven equipment may be supplied. Many vendors and some manufacturers provide two separate lubrication systems One for hot bearings in the gas turbines and another for the cool bearings of the driven compressor. These and other lubrication systems should be detailed in the specifications. 

Customer supplied products that are issued for incorporation into supplies don t often require maintenance however, items for use in conjunction with the contract may be retained for such a duration that maintenance is necessary. If the products require any maintenance you should be provided with a maintenance specification and the appropriate equipment to do the job. Maintenance may include both preventive and corrective maintenance but you should clarify with your customer which it is. You may have the means for preventive maintenance, such as lubrication and calibration, but not for repairs. Always establish your obligations in the contract regarding customer supplied product, because you could take on commitments for which you are not contractually covered if something should go wrong. You need to establish who will supply the spares and re-certify the equipment following repair. 

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). 

The performance of soluble oils is made possible not only by their high specific heat and thermal conductivity but by their low viscosity, which permits good penetration into the very fine clearances around the cutting zone. Consequently, these fluids are used mainly where cooling is the primary requirement. Lubricating properties can be improved by polar additives, which are agents that enhance the oiliness or anti-friction characteristics. Further improvements can be effected by EP (extreme-pressure) additives, which are usually compounds of sulfur or chlorine. 

Most oil companies offer a planned lubrication maintenance (PLM) service that will meet these requirements with the minimum of effort on the part of the customer. These schemes provide logical routing for the lubrication operative, balanced workloads and clear instructions to those responsible for specific tasks associated with lubrication and fault-reporting facilities. Many schemes are now designed for computer operation, which also accommodate plant and grade changes, operation costs and manpower planning. It is essential that any such scheme should be adaptable to individual requirements. 

The specific installation procedure is dependent on the type and mounting configuration of the coupling. However, common elements of all coupling installations include spacing, bolting, lubrication, and the use of matching parts. The sections to follow discuss these installation elements. 

Lubrication plugs must be clean (to prevent the introduction of contaminants to the lubricant and machine surfaces) before being installed and must be torqued to the manufacturer s specifications. 

Defined maintenance procedures should include model or manufacturer specifics and a list of parts to be inspected, cleaned, lubricated, replaced, and/or calibrated. The replacement part numbers, cleaning solutions and lubricants, and calibration standards, along with the manufacturer s maintenance procedures to be followed, should be specified. Documentation is easily managed by creating a one-page checklist of instructions or performance parameters that can be checked off as each task is completed. Any issues or comments can be captured directly on the checklist. Provisions for failure or out-of-tolerance notification need to be clearly defined, as the equipment cannot be put back into service until the performance has been verified by conducting a performance qualification. 

The agents in this class are bicyclophosphates and bicyclothiophosphates. This class of agents is not specifically listed in the Chemical Weapons Convention nor is it covered by the language of the general definitions in the Schedules. Some of these chemicals have been used as fire retardants, oil lubricants, and for medicinal research. They also occur as breakdown products in some synthetic turbine engine lubricants and some rigid polyurethane foams. 

Ointments are semisolid preparations that are intended for external use. Ointments may contain either finely powdered drugs or their mixtures, liquids, and other drug forms incorporated into appropriate bases. They are applied to the skin for their physical effects as emollients (which make the skin more pliable), protectants, lubricants, and drying agents. Ointment bases are also used as vehicles in which to incorporate topical medications which exert specific effect. There are four types of ointment bases, namely, oleaginous, absorption, water removable, and water soluble bases. 

Some self-lubricating grades of polycarbonate are marketed, containing specific additives and reinforced with glass or carbon fibres. The coefficients of friction are in a good range, from 0.1 up to 0.21. Wear resistance is not as good as for PA 66. 

Some self-lubricating grades of polyarylketones containing specific additives, and possibly reinforced with glass or carbon fibres, are marketed. The coefficients of friction are good, for example 0.1 at room temperature, and remain unchanged at high temperature 0.12 at... 

Maintenance, servicing, and recharging should be performed by trained persons having available the appropriate servicing manuals, the proper types of tools, recharge materials, lubricants, and manufacturer s recommended replacement parts or parts specifically listed for use in the specific fire extinguisher. 

Catalysts, colorants, foaming agents, biocides, lubricants, and antistats are also used as additives for polymers. Although foaming agents reduce the specific gravity, the other cited additives, when used in moderate amounts, have little effect on the physical or thermal properties of the polymers. 

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