A frame work for comparative wear based failure analysis of CNG and diesel operated engines

Application of alternative fuels in engines is essential and encouraged for their non-polluting nature as well as shifting from fossil fuel use. But engine life span should be investigated for better efficiency and economy. In this study, industrial diesel and CNG engines have been investigated periodically for the surface degradation through wear. Ferrographic techniques have been applied on the used lubricating oils for checking the engine wear conditions. Different wear parameters have been obtained by quantitative ferrographic technique. Bath-tub curves have been plotted for the cases based on their severity index. Qualitative ferrographic technique enables to obtain images of the wear particles. Fractal dimensions of the wear particles have been compared for both the cases. The results indicate that CNG engine requires early maintenance and the diesel engine can run more time considering severity index. Some failure parts are physically observed at the end of experimented running hours. The results reveal that the failure of CNG engine happens early and consequently economy loss is more for CNG engine compared to that of diesel engine. Implementation of circular economy concept is suggested for regaining economy from the damaged parts of engine. This comparative analysis is beneficial for better industrial resource utilization. •Failure through wear investigations are performed for CNG and diesel engines.•Severity index based bath tub curves suggest early maintenance of CNG engine.•Qualitative results are analysed further through image processing techniques.•The computed fractal dimension of CNG engine is higher than that of diesel engine.•Circular economy is focused for regaining economy for the damaged components.