Substitute a new brand for one previously in use

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Unformatted text preview: possible situations: ! Substitute a new brand for one previously in use. ! Select a brand that meets an equipment manufacturer's specifications. This will be accomplished by comparing producer's specifications with those of the manufacturer. Product selection starts by using a substitution list maintained by most lubricant producers. A substitution list usually shows the products of major producers and the equivalent or competing product by other producers. Substitution lists are useful but they have limitations. They may not be subdivided by classes of lubricants. Furthermore, it is difficult to do more than compare a lubricant of one producer with one given by the publishing producer. For example, consider three producers called A, B, and C. Producer A’s substitution list may compare B’s products with A’s, or C’s with A’s. However, B and C cannot be compared unless A has a product equivalent to both B and C. A user would need substitution lists from many producers to be able to effectively select more than one option. Many producers claim they do not have a substitution list, or are reluctant to provide one. As noted in Chapter 11, the chart of 13-5 EM 1110-2-1424 28 Feb 99 Table 13-1 Factors Affecting Lubricant Selection Operating Conditions Type Size Bearings Plain, needle roller, ball Shaft diameter rev/min Chain drives Links; number and pitch PCD of all wheels and distance between centers Chain speed ft/min Cocks and valves Plug, ball, etc. Compressors BHP, manufacturer’s name Couplings Universal or constant velocity Cylinders Material Operating Temperature Element Velocity Fluid being controlled Remarks Depends on properties of the fluid Gas temperature Max gas pressure rev/min rev/min Bore, stroke Cylinder, piston, rings Combustion and Combustion exhaust gas and exhaust temperature gas pressure BHP, distance between centers Crank speed, rev/min Gears Spur, worm, helical, hyperbolic Glands and seals Stuffing box Fluid being sealed Depends on design Hydraulic systems BHP Pump type (gear, piston vane) Hydraulic fluid materials ‘O’ rings and cups, etc. Lubricant type adjusting to loss rate Linkages Ropes Slideways and guides Radiated heat rev/min and heat generated Environmental heat conditions Steel hawser Diameter Method of lubricant application Relative link speeds, ft/s, angular vel., rad/s Frequency of use and pollution, etc. Surface relative speed, ft/min Reference: Neale, M.J., Lubrication: A Tribology Handbook. Butterworth-Heinemann Ltd., Oxford, England. “Interchangeable Industrial Lubricants” and “Guide to Synthetic Lubricants” published by Plant Engineering Magazine (PEM) can be helpful. The PEM charts correlate products of many producers. The chart of synthetic lubricants correlates products by category (class). (4) A substitution list or chart is valuable because it correlates the array of brand names used by producers. Furthermore, it eliminates producers who do not have the desired product in their line. A substitution list should be regarded as a starting point to quickly identify potential selections. The lists 13-6 EM 1110-2-1424 28 Feb 99 Table 13-2 Types of Additive Oil Required for Various Types of Machinery Type of Machinery Usual Base Oil Type Usual Additives Special Requirements Food processing Medicinal white oil None Safety in case of ingestion Oil hydraulic Paraffinic down to about -20 EC (-4 EF), naphthenic below Antioxidant Antirust Antiwear Pour point depressant VI improver Antifoam Minimum viscosity change with temperature; minimum wear of steel/steel Steam and gas turbines Paraffinic or naphthenic distillates Antioxidant Antirust Ready separation from water, good oxidation stability Steam engine cylinders Unrefined or refined residual or high-viscosity distillates None or fatty oil Maintenance of oil film on hot surfaces; resistance to washing away by wet steam Air compressor cylinders Paraffinic or naphthenic distillates Antioxidant Antirust Low deposit formation tendency Gears (steel/steel) Paraffinic or naphthenic Antiwear, EP Antioxidant Antifoam Po...
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This note was uploaded on 02/09/2012 for the course MECH 84 taught by Professor Mba during the Spring '11 term at LDSBC.

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