Correlation Between Agricultural Tractor's Diesel Engine on Road Service Load and Regulations for Exhaust Emission Testing

There is obvious great difference between emission tests for the on road and off road vehicle's diesel engines. This fact is based on unparallel service load of engines installed on those vehicles. But it is true that agricultural tractors are frequently used for haulage and similar applications in regular on road conditions. In those circumstances their contribution to the total emission in the road environment is unavoidable. Based on that, study presented in this paper strictly relates to agricultural tractor operation down the road. This is due to the fact that in rural areas, the tractors are used for towing trailers on the roads in approximately 50% of the total life cycle.

The main purpose of this paper is to investigate the relations between real service load of the diesel engines installed in the agricultural tractors during haulage and regulations that are in force for official exhaust emission testing. The paper presents results of a number of typical agricultural tractors' applications on the local roads, village roads, etc. Having in mind that exhaust emission tests are frequently improved it is of interest to compare achieved results with some existing tests and proposals for further improvement.