Equivalent Oils Selection Procedure

Most industrial machinery and equipment used in our country are imported from abroad, so the oils and greases listed in operating manuals are always foreign brands. Often, these oils and greases are recommended or imposed on users by the machinery manufacturers themselves. Some machinery manufacturers suggest alternative options for these oils, while others impose only a single brand and product. Imposing specific brands or products on users is not an acceptable practice. These oils are products whose properties and chemical composition are known approximately, and can even be determined precisely through laboratory analysis. Furthermore, machinery manufacturers imposing only specific brands does not align with international and national competition rules. Some machinery manufacturers list closely valued alternative products and even provide important product specifications, emphasizing that if these specifications are met, the product can be used in the machine. To identify equivalent oils to those recommended by imported machinery and equipment manufacturers, following the procedure below often leads us to sound results: In the first stage, the technical specifications of the oil, which we refer to as PDS, must be examined. Technical specifications are parameters that reflect the operating characteristics and fundamental properties of the oil. The stated parameters are values measured in laboratory analyses using test methods standardized by institutions such as ASTM (American Society for Testing Materials) or DIN (Deutsches Institut für Normung), and these values represent the characteristic values that should be present in the oil.

The Principal Parameters Are as Follows:

• TBN (Total Base Number): Indicates the amount of alkalinity in the oil as mg potassium hydroxide/g. TAN (Total Acid Number): Shows as mg KOH/g the amount of alkali capable of neutralizing acid concentration present in the oil. Viscosity Grade: A value that reflects the oil's flowability at 40°C on a friction force/second scale. As viscosity increases, the oil's flowability decreases, since friction resistance rises. As viscosity decreases, the oil becomes more fluid and thinner. Pour Point: Particularly important for oils used in cooling systems or cold winter environments, it is the degree of flowability before the oil freezes. Flash Point: The degree Celsius at which oils ignite. Cloud Point: The degree Celsius at which the oil transitions to freezing or becomes cloudy. Drip Point: A measure particularly used for greases, indicating the degree Celsius at which the grease begins to flow under heat. Aniline Point: Expressed as the degree Celsius at which the oil reacts with aromatic (colored and odorous) compounds within it. A high aniline point reflects that the oil contains fewer aromatic compounds. NLGI Grade: A measure of grease consistency. It is a measure of the resistance of grease to penetration. Depending on the grease's consistency, it is graded on a scale ranging from 000 NLGI to 6 NLGI. Specific Gravity: The ratio of the oil's unit weight to its unit volume, expressed in g/litre. Timken Load Test: A test method designed especially for greases, reflecting the grease's load resistance as kg/minute. NSF H2 Code: Oils and greases approved under this code are not suitable for contact with food products at the points where they are used during the production process. However, oils and greases under this approval comply with environmental regulations and are in the category of environmentally safe products. NSF H3 Code: Oils and greases approved under this code are suitable for direct and prolonged contact with produced food.

2. In the second stage, the test parameters of the oil or oils considered equivalent are examined as determined and published using the same test methods. When comparing these values, if the test method is according to an ASTM standard code, the results published according to the same method are reviewed. In these results, there are generally some tolerance deviations. In fact, a specific oil itself may have deviations from its main specifications within small tolerances at the end of production, but the deviations must fall within acceptable limits. For example, the viscosity (flowability) of a cooling compressor oil measured at 40°C may be between 65–72 centistoke with a 5% deviation, instead of 68 centistoke, and this is an acceptable tolerance. As in medical tests, just as the upper and lower limits of values that should be present in blood such as cholesterol, triglycerides, sodium, potassium, and glucose are defined, specification ranges for oils are similarly accepted within standard ranges. For equivalent oils, technical specifications being within tolerance values is sufficient. 3. In the final stage, if possible, the oil considered equivalent is used in the relevant machine or equipment and operation results are examined. This is generally done in two ways. If the tested oil has no deficiency in the machine's normal operation efficiency and performance, that oil is now completely accepted as a compatible and equivalent oil. The second method involves sampling the equivalent oil tested in the machine after a certain number of operating hours and subjecting it to laboratory analysis. If the analysis results obtained from this meet the sought technical specifications, it is sufficient proof for equivalence.     Kudret Tan Senior Industry Engineer En-Ser Taahhüt ve Ticaret