Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/229047
LUBRICANT SPECIFICATION PRODUCT: EXTREME PRESSURE LUBE OIL MAINTENANCE CODE NUMBER: MC - 43, 51, 87, 21, 93, 71 & 31 Test No. Description Test Limits Comments D-2270 Viscosity Index Minimum=85 D-445 Viscosity See Figure 3 D-92 Flash and Fire Points D-97 Pour Point See Figure 3 D-189 Conradson Carbon Should contain no more than 2.5% residue D-130 Copper Corrosion No worse than Class1-b D-874 Sulphated Ash Matter of record D-892 Foam Characteristics Less than a trace after 10 minutes D-665 Rust Prevention No rust after 24 hours D-2711 Demulsibility See Figure 3 D-1298 API Gravity Matter of record D-1500 Color Matter of record D-3604 Elastomer Compatibility Weight change +2% -1%; Volume change +5% -2% D-4172 4-Ball Wear Limit is 0.35 mm with 40 kg load ISO 4606 ISO Cleanliness Cleaner than 21/18 on delivery D-2893 Oxidation Test Viscosity increase less than 5% D-664 Neutralization Number Not to exceed 1.0 D-2782 Timken Test Pass 60-pound load D-2783 4-Ball EP Weld=250 kg; LWI=45 kg FZG Gear Tooth Wear 9 stages; wear less than 10 mg 3 hours at 212°F Procedure A 312 Hours (13 days) at 100°C Figure 2. A typical performance specification for a gear oil 4. Tanks permanently installed in the plant may have the MC number stenciled on them if there is little chance a change will be required. Vendor Relationships One of the main reasons for the specification system is to prevent "cozy" relationships between vendors and plant personnel. When this situation occurs, prices tend to rise whether quality rises or not. Conflicts then occur between plant personnel and the purchasing department, as the latter attempts to stabilize prices. Using the specification system allows an "arm's length" relationship. Looking primarily at the test results promotes objectivity. Of course, quality consistency, dependable deliveries and knowledgeable service are considered as well. No one likes vendors who provide inconsistent quality, unreliable deliveries or spotty service. Adjusting Specifications The performance specification should be considered a "living" document. It must be periodically adjusted to reflect new knowledge. Once written, the specification may become outdated by new developments in the field. New tests may be devised that assess a parameter better than previous versions. The consensus of opinion among industry experts might also change regarding which parameters are important or which test provides the best measurement. Therefore, vendors are encouraged to offer suggestions on ways to improve the specifications. Their input can be valuable. Exceptions It does not pay to employ performance specifications on low volume items. Below a certain dollar amount, the use of specifications is a waste of time. Simply find something that works and use it if the cost is not excessive. However, in a multi-plant organization, small quantities in several plants can add up to enough money to make using a specification worthwhile. Every situation is different, and good judgment must be used. One of the questions that might be asked when considering the use of specifications is: "Do we need to consolidate our products?" According to the Pareto principle (80/20 rule), 80 percent of the lubricant volume in a plant should be concentrated in 20 percent of the individual products. Take a survey of the products and the www.machinerylubrication.com | November - December 2013 | 11