Scavenge fires.

[Tim Gibbs]

Originally Posted by Sherman

I was the Jun. Enginer on the 8/12 on the M.V. "Wanstead" (Doxford engine). I was looking at the engine water temps when a spark hit me on the arm, stung a bit. I told the 4th but he didn't belive me but I insisted. He told the 2nd and I got the 3rd degree from him again The bridge rang, it was the 3rd mate asking what we were doing as there was clouds of smoke coming out of the funnel. It was a fire in the generator exhaust. I also had a small burn on my arm. The 2nd said just let it burn out

What seems like 100 years ago ( but was actually only just over 50!), we had been cobbling together the repair to a fractured 75LB6 Doxford crankshaft and we were preparing for the first engine trial. We had been stopped 3 or 4 weeks and had the same T47 Allan generator running with very little load.
Being a 2-stroke, it didn't like that very much and in protest pumped lub. oil into the exhaust manifold which lay there quite happily until the load leaped when we started the two big starting air compressors. At this point the exhaust bellows decided to fracture and a stream of oil came out which, by now, was on fire. This narrowly missed the Lloyds surveyor who was already a bit nervous but he was quite impressed when the 3/E very quickly produce a oil drum in one hand to catch and contain the oil and a fire extinguisher in the other. He did ask however if this was a regular occurrence as it seemed to be a well practiced response!
Many years later we had an anchor handler with four Wichmann 9AXAG 2-stroke engines that had been idling for hours and then went to full load. Same problem as above but a different result - the burning oil in the exhaust manifold on one engine turned the turbocharger into a gas turbine. It took quite a few minutes to blank off the air intakes to extinguish the fire.

[Makko]

Originally Posted by Tim Gibbs

Many years later we had an anchor handler with four Wichmann 9AXAG 2-stroke engines that had been idling for hours and then went to full load. Same problem as above but a different result - the burning oil in the exhaust manifold on one engine turned the turbocharger into a gas turbine. It took quite a few minutes to blank off the air intakes to extinguish the fire.

It happened on the Barber Perseus too! Sulzer 9RND90 engine. After "slow steaming", the turbo coked up and, so, when they went to FSA one of the three BIG turbos blasted off! A mate on board at the time said he was mesmerized with the tacho going off the clock and bending the pointer until the 2/E screamed at him "to take cover" [edited for people of a sensitive disposition] in case a blade "excursion" occured! As you said, the solution was to remove floor plates an slide them, slowly, into the airtake and strangle the TC.

After that, we were advised to go to full ahead for short periods during slow steaming to "blast the crap" [technical terminology!].

Rgds.
Dave

[Tim Gibbs]

Originally Posted by Makko

It happened on the Barber Perseus too! Sulzer 9RND90 engine. After "slow steaming", the turbo coked up and, so, when they went to FSA one of the three BIG turbos blasted off! A mate on board at the time said he was mesmerized with the tacho going off the clock and bending the pointer until the 2/E screamed at him "to take cover" [edited for people of a sensitive disposition] in case a blade "excursion" occured! As you said, the solution was to remove floor plates an slide them, slowly, into the airtake and strangle the TC.

After that, we were advised to go to full ahead for short periods during slow steaming to "blast the crap" [technical terminology!].

Rgds.
Dave

Don't remember what happened to the T/C on the Wichmann but it couldn't have been very good for its health as the engine was out of service for quite a while. I do remember however that this engine was fated as later a balance weight came adrift and did a couple of circuits around the crankcase before it escaped into the engine room

[David Lambert]

I sailed on a container feeder vsl around the Gulf to India and Sri Lanka. Main engine was a clapped out Mitsubishi UE, liners all overworn, no spare rings or liners just the UBG as best we could find. First scavenge fires started crossing to India from Dubai. We probably had three and followed all the recommended procedures, slow engine, increased cyl lube, boundary cooling carefully allow to cool out, open up space carefully and clean gunk out etc. On the way from Colombo to Muscat we had 14 fires. Procedures changed fairly quickly and descended into to stop engine, identify unit with fire, open scavenge inspection port and shove fire hose in. Put fire out scrape rubbish out box and off again. A three hour stoppage changed to a half hour and get going and we never cracked a liner or damaged anything. Company never did give us any liners or rings whilst I was there and we did every unit at least once to try to keep her going.

[John Gowers]

I was 14 years at sea before going to rigs and sailed mostly with Sulzer and B&W engines on motor ships also never saw a scavenge fire although as had been said before I did read about it in text books.

I saw one galley chip pan fire on the Euroliner extinguished by the C/E using fire blanket and one switchboard fire on the Chemical Explorer causing a blackout this fire was put out by myself and the J/E using CO2 extinguishers. Never saw a fire on rigs in 26 years .