RELIABILITY IMPROVEMENT AND SIMPLIFICATION OF METHOD FOR MEASURING EXHAUST GAS FROM EARTH-MOVING MACHINERY

Abstract

 Exhaust gas from earth-moving machinery is regulated using chamber tests for the engines installed in the machines. On the other hand, in line with the trends in on-road vehicles, measurements on exhaust gas emitted from working earth-moving machinery have been reported in Japan and other countries. The reliability of such measured values must be determined in order to discuss the magnitude, and measurement methods must be simplified in order to obtain much data on various machines in the future. This paper proposes using CO₂-based emission rate (g/kg-CO₂) to evaluate the amount of gas emissions, and choosing ‘Idling’ and ‘Grading (simulated work)’ when measuring working machines in order to improve the reliability of measured values and to simplify the measurement. It is predicted that measurement of 5 minutes of ‘Idling’ performed three times, and 60 cycles of ‘Grading (simulated work)’ performed three times by different machine operators can control the precision of estimated random errors of the measured NOx values to no more than 10% with 95% reliability.