Crankcase explosion is caused due to the overheating of one of the cylinders in the main machinery space. The consequences of the explosion is severe and it affects the working of other engines.
Although there have been many occurrences of crankcase explosions recorded, there is no official body to whom they can be formally reported. As a consequence these occurrences have been reported randomly which has made it difficult to statistically analyse the number, the root cause and the severity of the explosions.
To avoid an increase in risk of crankcase explosions occurring, the engine makers and classification societies have developed common rules for oil mist detection and crankcase relief valves.
Concerns have also been raised over the use of the flash point of the lubricant as a reliable indicator for the risk of crankcase explosion. The flash point test has been adopted by all major used oil laboratories as a service standard to vessel operators.
This document provides an overview of several conditions that causes crankcase explosion and on the over reliance on the flash point as an indicator for crankcase explosion.