Liberty ship Jeremiah O’Brien save from pier fire

Concerto

Concerto

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This Liberty ship Jememiah o'Brien has been saved from a fire on the pier she is moored alongside.
Shocking images of pier fire in San Francisco

More information on the Jememiah o'Brien.
SS Jeremiah O'Brien - Wikipedia

Liberty ships were built to a standard design in 18 shipyards in the US and produced 3 ships every 2 days. They were fitted with a compound steam engine of obsolete design was selected to power Liberty ships because it was cheaper and easier to build. When the first started building, they took 230 days and as production increased this dropped to an average 42 days. The fastest build was just 4 days 15½ hours!

Out of the 2710 Liberty ships built, over 2400 survived the war, but several were lost later to poorly cleared minefields. Large numbers were bought and used as merchant ships after the war. She is only one of 4 remaining examples.
Liberty ship - Wikipedia
 
Her engine room was used in scenes for the Titanic film that stared Kate Winselet. Was there not a submarine berthed there as well, open to tourists?
 
Dad's nearly finished building the model of her

His first ship was a Liberty ship .. he does not have particularly fond memories of the engine room!
 
Visited the Medway a few years ago.
Excellent book available about her restoration and her voyages. Appointment In Normandy.
IBSN0-9637586-4-0.
Chapter noting her arrival in the Medway and sailing past her sister ship located just off Sheerness.
 
Thank you oldgit I forgot to mention the wreck of the SS Mongomery at the entrance to the Medway was also a Liberty ship. Still loaded with a quantity of ammunition despite having her back broken.
 
Concerto said:
Thank you oldgit I forgot to mention the wreck of the SS Mongomery at the entrance to the Medway was also a Liberty ship. Still loaded with a quantity of ammunition despite having her back broken.
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We passed her several times in the 60s... eery feeling. They survey her at frequent intervals, but really don't want anybody near her. If she did go off, likely Sheerness would be drowned.
 
Many of them, if not all of them, were some of the first welded ships. The metallurgy of welding and design to limit stress concentrators was not developed and early ships had weld cracks which propagated and sank the ship. IIRC this was subsequently understood and addressed. I have a distant memory sitting in a metallurgy lecture and the story being described. The issue was the Heat Affected Zone being brittle and cracking, compounded by design that was based on riveted construction which would otherwise have limited the crack propagation. Maybe others know the story better.
 
BlowingOldBoots said:
Many of them, if not all of them, were some of the first welded ships. The metallurgy of welding and design to limit stress concentrators was not developed and early ships had weld cracks which propagated and sank the ship. IIRC this was subsequently understood and addressed. I have a distant memory sitting in a metallurgy lecture and the story being described. The issue was the Heat Affected Zone being brittle and cracking, compounded by design that was based on riveted construction which would otherwise have limited the crack propagation. Maybe others know the story better.
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Apparently, the steel used became brittle at North Atlantic temperatures and cracked at stress concentrations such as hatch corners. This wasn't fatal in a riveted ship because cracks stopped at the edge of plates, but in a welded ship the cracks could propagate indefinitely, resulting in structural failure. It was overcome by design changes to avoid stress concentrations. It was shown that the welds themselves rarely failed.
 
AntarcticPilot said:
Apparently, the steel used became brittle at North Atlantic temperatures and cracked at stress concentrations such as hatch corners. This wasn't fatal in a riveted ship because cracks stopped at the edge of plates, but in a welded ship the cracks could propagate indefinitely, resulting in structural failure. It was overcome by design changes to avoid stress concentrations. It was shown that the welds themselves rarely failed.
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Their was a bit more to it. Dr Weir was asked to look into it and found out that the metal just off the weld would turn crystaline and crack, due to bad heat conductivaty. Now know as a Weir fracture. But, there was also some very bad welding done with the welders filling in gaps with spare rods and welding over the top. The crack could propogate very fast, once started and the vessel break in two in a matter of seconds. I think that several welders were prosecuted for dangerous work.
 
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