Real-Time Oil Consumption (RTOC-III™) measurements were made on a 1,500 kW EMD 16-645E locomotive diesel engine, as part of a program to evaluate commercially available cylinder kits that hold the potential to reduce lubricating oil consumption and hence reduce exhaust particulate matter emissions. The RTOC technique uses sulfur dioxide (SO2), as measured in the exhaust gas stream, as a tracer for oil consumption. The engine was operated on an ultra-low sulfur diesel fuel and commercially available SAE grade 20W40 mineral-based lubricating oil. Knowing the SO2 concentration in the exhaust, the air and fuel flow rates, the lubricating oil consumption rate can be calculated in real-time, i.e. on a second-to-second basis. Use of RTOC on the locomotive engine application has proven to be a cost-effective tool for mapping steady-state lubricating oil consumption rate. Where traditional volumetric oil consumption measurement techniques can take several days to obtain the oil consumption rate from a single operating point, the RTOC technique takes only about 10 minutes per operating mode. Applying this technique, the test duration can thus be tremendously compressed, as compared to the volumetric technique. In addition to cost savings, the repeatability of the data is much improved by applying this novel technique. In this program, steady-state oil consumption was determined at 10 steady-state operating conditions typical of North American freight locomotive operation.
Investigation on on-line monitoring method for lubricating oil deterioration