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Old 21st October 2020, 11:16
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Tim Gibbs United Kingdom Tim Gibbs is offline
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Join Date: Mar 2019
Location: Bideford, North Devon
Posts: 121
Machinery Casualties

Having a morbid interest in such things I have been looking at the history of machinery spaces casualties over the last 60 years. In the period 1960 -90 it seems the majority of casualties involved large scale mechanical and occasional electrical failures but with relatively few fires That certainly mirrors my own experience. I think I had more than a fair share that touched my life in one way or another during that period at sea and in management ashore ; main engine crankshaft fractured in two places, damaged main engine crankshaft pins and journals requiring in situ machining, broken generator crankshaft, hydrauliced main engine cylinder, generator explosion , microbial crankshaft attack, five main engine bedplate failures, crankshaft balance weigh detachment, air start line explosion, engine room flooding, alternator stator turned in the casing and a connecting rod failure. However, in that period I only encountered one engine room fire.
In the subsequent 30 years there appear to be fewer such failures but a large increase in the proportion of fires. And, as if to make the point, last night there was an engine room fire that immobilised the Pride of Hull off Immingham. In these most recent 30 years the standard of reporting and investigation had vastly improved but it is unlikely it would have changed the proportions significantly. Improvements in design, materials, manufacturing and lubricants will account for the majority of the general reliability improvement of machinery but why the increase in the number of fires?
Not unsurprisingly most machinery space fires result from fuel or lubricating oil leaks and the majority of those seem to be on medium speed engines. Fuel systems have become more complex and engines more highly rated and compact. Shielding areas vulnerable to oil leaks and protection of hotspots is much improve but doesn’t seem to get sufficient attention in service when it is often allowed to deteriorate negating the design improvements.. Engineers no longer continuously patrol the machinery spaces as they have become much more reliant on sensors and CCTV systems so little problems are often not identified before they escalate into a major incident.
Fire fighting training is now much improved but regrettably there remains some serious issues relation to the systems crews have to rely upon in an emergency. There have been a shocking number of failures of the fixed fire fighting systems ; CO2 systems that fail to discharge correctly, water spray systems that fail through blocked nozzles or problems with the power supply and foam systems that don’t make foam. These issues wouldn’t necessarily affect the initialisation of a fire but would certainly influence the outcome. Such failures reflect very poorly of the inspection and maintenance regime carried out, usually by the system manufacturer. However, owners cannot absolve themselves by relying entirely on the manufacturer and they must have some oversight themselves at it they who are responsible for ensuring that they vessel is safe in all respects.
And then there is the emergency generator! It often seems to have insufficient capacity for the situation that develops in an emergency and, despite being tested for a few minutes each week, often fail with voltage control problems and overheating when used in anger for it’s intended purpose. In one recent incident, on a five year old ship, the generator had only accumulated about 50 running hours but failed under emergency conditions after 12 hours running. Perhaps it’s time for a rethink; why not make the machine much bigger and allow it to be occasionally used to supplement the power supply in normal operation? It could be limited to running, say, 1,000 hours per annum but if so used it is likely to be totally reliable in an emergency situation and would be able to supply a greater range of services than is currently the case.
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