EVALUATION OF MARINE DIESEL ENGINE OIL WATER SEPARATION PROCEDURES

Marine medium-speed diesel engine lubricants must possess good water separation properties for efficient engine operation. On shipboard and land use, a centrifugation process is normally used to release water from the lubricant. A laboratory centrifuge test procedure has been developed which simulates actual shipboard operation. It provides an accurate assessment of the water shedding characteristics of a test lubricant. Formulations that possess excellent water tolerance properties can be identified for field evaluation onboard ship. Centrifugation results of various commercial marine oils are compared with those from ASTM D1401 and other laboratory water tolerance procedures. Data on both new and used oils are included. The centrifuge procedure has demonstrated its value in more accurately measuring the true water-shedding ability of an oil. It represents an improvement over existing laboratory water tolerance tests for developing better marine crankcase lubricants.