Ships Nostalgia - View Single Post - Doxford Engines 3-legged
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Old 19th June 2019, 14:38
Tim Gibbs's Avatar
Organisation: Merchant Navy
Department: Engineering
Active: 1960 - Present
Join Date: Apr 2012
Posts: 69
Originally Posted by JKB View Post
Alfons asked:
Who can tell more about his experience with the starting assister?

I was on the builder's sea trials of the "City Of Plymouth" out of Appledore Shipbuilders and I believe the problem with the over-enthusiastic dead-band assister occurred during that trial. I can't supply much detail as I kept out of the way, it seemed to me that the Doxford men had enough on their plates without me poking my nose in as well.

I thought it best to concentrate on the Blackstone generators that I was there to look after, but I seem to remember they had quite a bit of bother with flexible pipes failing and covering the job in oil prior to the big bang. The engine was a 58JS2, I believe.
I was Ellerman's Project Engineer for that class of ship built at Appledore. Great ships - shame about the 58JS3s! I had wanted the engine to drive a CP propeller at constant speed but the boss wouldn't have it. I think it was killed by the yard wanting a 45k extra which is a shame as it would have transformed the engine by doing away with the starting assister and probably considerably reduced the piston ring and liner wear problems encountered in service. Interestingly we found that the dead band was not as big as the theory suggested and it was further improved on the second shop when we changed the phasing of the propeller with the crankshaft .
At the beginning of the contract we were badly deceived by British Shipbuilders and Doxfords who told us the 58JS3 was a slower speed(220 rpm) version of the "fully developed"Seahorse. Unfortunately that was totally untrue but it was too late before we found out the full truth. The first engine was over 6 months late and development had to continue with the ships in service .
Perhaps a TM410 or K Major wouldn't have been so bad after all !!
Never let anything mechanical know you are in a hurry.
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