CM Technologies has introduced a new sensor for the detection of early onset cylinder wear on two-stroke marine diesel engines, following the completion of ship trials to confirm its effectiveness.
The trials onboard containerships and a two-stroke engine Baltic ferry showed it was possible to measure the friction in the cylinder when the engine is still running. Scuffing, the term used to describe extreme wear following breakdown or failure of the lubricating film between the piston rings and cylinder liner, can be costly to repair and may potentially result in catastrophic engine failure.
The detection technology uses acoustic emissions sensors to analyse the operating environment within the piston cylinder. Capable of operating without requiring the engines to be stopped, the sensor detects changes in high frequency vibration and stress waves when accumulated energy is rapidly released on the piston rings and cylinder liner’s surface.
AE sensors – electromagnetic acoustic transducers with built-in amplifiers optimised to detect sound waves – can locate material crack formation, friction, delamination and cavitation, revealing underlying problems with the lubricant being used. The data is then analysed by the company’s software.
“One of the big problems for the reliable detection of sudden severe liner wear is that the long running time of a marine diesel engine has made it virtually impossible to visually detect scuffing as it happens,” said CMT’s Managing Director Matthias Winkler.
“When sudden severe liner wear occurs, piston damage is quick, spontaneous and without warning. Current methods such as drain oil analysis, liner wall temperature monitoring and visual port inspections are inadequate as they indicate something is wrong when it’s too late.”
“Timing is crucial. The technology we have developed alerts operators with enough time to be able to do something about it.”
