Garin, Paul V.
Engineer of Research and Mechanical Standards, Southern Pacific Co., San Francisco, Calif.
Pages: 38 Published: Jan 1957
As the result of an extensive research program to develop less critical fuels for use in its diesel locomotives, the Southern Pacific Co. adopted the so-called “economy” distillate fuels for general service early in 1954. Since that time, these distillate fuels, with minimum cetane rating of 34 and maximum sulfur content of 1 per cent, have been successfully used in diesel locomotives with resultant economies both to the railroad and the oil supplier. With the satisfactory use of less critical distillate fuels well established, the Southern Pacific fuel research effort was directed to the possibilities of employing even lower cost fuels in its locomotives. During the initial stages of the research program, a successful test was conducted with an experimental fuel identified as X-1. This fuel, which was a blend of heavy straight-run distillates and cracked stocks characterized by high viscosity (72 sec Saybolt Universal at 100 F) and high pour point (55 F), required heating to approximately 150 F for injection. The fuel was of a waxy nature, containing relatively high (0.90 per cent) sulfur content, but having a cetane number of 48. By means of a heat exchanger using cooling water, the fuel was heated to injection temperature. Two Electro-Motive Division (EMD) model 567-B engines in main line freight service were equipped with heat exchangers to handle X-1 fuel. Underbody fuel tanks were insulated with a mastic coating to retain heat, and a circulating heating system from the tank through the heat exchanger and back to the tank maintained necessary temperature for this high pour point fuel in the tank. After the test period of six months in main line freight service was completed, during which each test unit consumed approximately 100,000 gal of X-1 fuel, inspection was made of assemblies removed from each unit. The appearance of engine parts and wear measurements were considered normal in all respects as compared to units operating on regular straight-run distillate fuel.
Paper ID: STP46895S