Measuring Fuel Savings From Soy-Based Gage-Face Lubricant on Rail Track Straightways

Grant# 03-05
Principal Investigator: Dr. Lou A. T. Honary
Organization: Ag-Based Industrial Lubricants Research Program, University of Northern Iowa
Technical Area: Efficiency & Renewable Energy

Final Report
Available for review by contacting the Iowa Energy Center,, (515) 294-8819.

Public Abstract

Railroad operators have historically lubricated track curves to achieve fuel savings and reduce wear as wheel flanges drag against the inside edge of the inner rail. To date, however, the cost/benefit relationship of applying gage face (GF) lubrication along straightaways is relatively unproven. At the same time, soybean based lubricants are becoming increasingly recognized for specific features in which they demonstrate inherently superior performance and ability. Soybean base oils generally demonstrate better thin-film strength, cohesion, adherence to metal, and higher lubricity, which are all central to the requirements of rail flange lubricants.

This project is a two-phased study to quantify the substitution value of soy based wayside GF lubricant in terms of average fuel savings, and to differentiate performance from the market leading petroleum. It is expected that the performance results of the soy-based version will justify the lubrication of straightaways as a substitute for fuel consumption. The project will bring together key involvement, including UNI-ABIL, the Norfolk Southern Railway Portec Rail Incorporated, and the Transportation Technology Center (TTCI), as subsidiary of the American Association of Railroads.

Although the potential of saving fuel with gage face (GF) lubrication is generally understood, a range of variables obscures the ability to identify a summary relationship between the cost of fuel and the cost of lubricating. In practice, variations in locomotive efficiency, infinite combinations of train configurations, operating speeds, wind velocities, track grades, curvatures, lubricator access points, and a host of other issues all combine differently to affect a specific cost benefit comparison.

A component of this study is to test the statistical reliability of the cost/benefit relationship between fuel savings and lubricant application rates, when used on track straightaways. The model will also be used to illustrate specific performance benefits of soy-based lubricants that are evident from prior testing and other studies.

Laboratory testing at UNI-ABI has consistently demonstrated improved thin-film strength, cohesion, adherence to metal, and higher lubricity for soy-based alternatives. Likewise, a prior field study (designed to evaluate “pumpability”) demonstrated that a soy-based GF lubricant demonstrated better energy savings, better carrying ability, and reduced top of rail contamination at a dosage rate approximately half that of the control blend. The control version was a market leading petroleum with comparable unit price.

Project Objectives

Based on the evidence and indications of previous studies, the objectives of this project are stated as follows:

1. Differentiate and quantify optimal dosage rates between the market-leading GF lubricant and the soy-based alternative.

2. Define benchmark energy savings attainable by applying gage-face lubricant on straight track sections.

3. Define a general correlation between dosage rates (in pounds) and fuel savings (in gallons) that can be used as a “rule of thumb” to determine the annualized value of applying soy-based alternatives.

Since submission of this proposal, there has been further development in the use of soy based rail curve grease in biodegradation of the soy grease after application. Time permitting, an additional objective would be to evaluate samples of soil contaminated by each of the conventional and soy based greases to determine degree of persistence in the environment.