Analysis of a diesel generator cylinder failure

This paper analyses a catastrophic cylinder failure of a four stroke 14 V diesel engine of an electrical power plant when running to nominal speed of 600 rpm. The rated power of the engine was 7.5 MW and before failure had accumulated 80,000 h in service operating mainly at full load. As a result, the piston and liner of cylinder 4 were broken; the crankcase and main crankshaft bearings next to this cylinder were also damaged. The mechanical properties of the liner (grey cast iron) and piston body (aluminium alloy) including tensile properties and Brinell hardness were evaluated. No signs of fatigue failure were identified in liner and piston. A finite element model of the liner has shown that the most heavily loaded areas match the fractured zones.