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Weak Rivets May Have Sped Sinking of Titanic
Pickens writes "Metallurgists studying the hulk of the Titanic argue that the liner went down fast after hitting an iceberg because the ship's builder used substandard rivets that popped their heads and let tons of icy seawater rush in. They say that better rivets would have probably kept the Titanic afloat long enough for rescuers to have arrived, saving hundreds of lives. The team collected clues from 48 Titanic rivets and found many riddled with high concentrations of slag, a glassy residue of smelting that can make iron brittle. To test whether this extra slag weakened the rivets, scientists commissioned a blacksmith to make rivets to the same specifications as those used to join steel plates in the hull of the Titanic. When the plates were bent in the laboratory, the rivet heads popped off at loads of about 4,000 kg. With the right slag content they should have held up to about 9,000 kg. Even a few failures because of flawed metal would have been sufficient to unzip entire seams, because as faulty rivets popped, more stress would have been placed on the good ones, causing them to break in turn. The shipbuilder, which is still in existence, denies it all."
... And here was me thinking that was just a nationalist myth. You mean the Belfast shipbuilders really did say that stuff about the Pope when they put 'em in?
Real Daleks don't climb stairs - they level the building.
And I thought that it was loose lips that sunk ships.
Why do people find the Titanic so fascinating? I still see documentaries come up every now and then. There were worse tragedies and boat disasters than the Titanic. Is it because it was a ship mainly for the rich that they said was unsinkable but did? For all the Titanic buffs, build a bridge and get over it... or will that have cracks too? Oh the humanity.
Analytic & algebraic topology of locally Euclidean meterization of infinitely differentiable Riemmanian manifold
My grandfather, who was a Marine in WWII, told me all sorts of stories of how the Navy's ships back then were pretty rickety. Reason being, aside from cheap labor, was that the assembly crews would have races in building the ships. The quality went down with the speed, like anything hand-crafted, and I'm not surprised to hear the same thing about the Titanic. While the Titanic was made by completely unlike laborers, they were probably/most likely under the same kind of stress that one normally expects when facing rushed work.
The Titanic has two sister ships the Olympic (built before) was known as "Old Reliable" retired and dismantled after sailing for 24 years, and the Britannic (built after, sunk by a mine)
If the rivets were such inferior quality why did the Olympic sail without problems (including being rammed by the cruiser HMS Hawke) for 24 years?
Puteulanus fenestra mortis
There are so many variables that after all these years, who knows?
Perhaps the Titanic had one faulty batch of rivets which just happened to be in the wrong place. Perhaps the shipbuilders thought they could save a bit of money.
The lack of lifeboats, the "woman & children first" and "rich people first" attitudes around that resource, the freezing cold of the water that killed within half an hour anybody floating in it, and the fact that the first ship to arrive arrived hours later 'cause the nearest ship wasn't paying attention to its radio.
Another hour or two on the surface would have just delayed the inevitable, but there was still nowhere else for the people to go.
"But remember, most lynch mobs aren't this nice." (H.Simpson)
-- Joe
The big thing here though is this "unzipping" thing I've seen quoted.
I'm interested if anyone knows about maritime riveting and can correct me because in aviation we not only use rivets of a standard design specification (predominantly) to reduce dissimilar metal corrosion but also they are riveted in set patterns that mean should one rivet fail then the resulting weakness and is to a greater degree minimised by the placement of other rivets. For example the most simple battle damage repair would be two sheets overlapping with a double row of staggered rivets at set distances (I forget the exact inches) - and that's a patch repair!
Unzipping, to me, implies that the metal was riveted in straight lines which would seem like an engineering faux pas of the highest order.
A thistle is a fat salad for an ass's mouth...
Jen McCarty was my labmate in grad school (we had the same adviser), so I heard about the Titanic rivets a lot.
Jen didn't know if all of the rivets were made of poorer-quality iron. She only had 48 to test (they're expensive to retrieve). I have no idea how those rivets were distributed about the ship. A statistician might be able to tell you how confident you can be with 48 sample out of population of hundreds of thousands. However, IIRC every single rivet tested was of the poorer quality.
I believe the rivets were pulled out of the Titanic itself. Even if they were gathered from the ocean floor around the wreck, I think it's highly unlikely that someone happened to dump bad rivets from the early 1900s in the middle of the North Atlantic right where the Titanic sunk.
Both Jen's grad-school research and TFA mention higher quality iron being used in ship rivets normally. While it was more difficult to test for slag in rivets 100 years ago, they were very good at knowing how to make better (read: stronger) iron, because ultimately you can just test the iron to failure and see how strong it was. Jen looked at iron from other structures built around the same time as the Titanic and they were definitely of a higher quality (I think TFA mentioned the Brooklyn Bridge).
Finally, slag doesn't grow in iron because they sit on the ocean for 100 years. These rivets are roughly an inch in diameter, and Jen cut them in half and looked inside them. There was corrosion on the outside, sure, but the impurities that are at issue here are embedded in the rivets. IIRC, slag is almost a glassy substance. It has different mechanical properties than iron, leading to stress concentrations in the iron surrounding chunks of it. These stress concentrations result in the iron failing under less overall stress than it would have otherwise.
Cover your butt. Bernard is watching.
The Olympic, five hundred miles off, make perhaps twenty-four knots in a pinch.
There were very few vessels that could match her speed. Carpathia, sixty miles off, could be pushed to fifteen - a nightmare four hour run through the arctic ice fields.
The North Atlantic is a mighty big ocean. Titanic had other problems.
The 24 hour radio watch was not standard. Titanic had a 500 KHz 5 KW Marconi spark-gap transmitter with a nominal range of 250 nm. She had far greater reach at night - but much would depend on the relative orientation of antennas and so on.
The best you could hope for in a receiver would be a very early vacuum tube design.
But operation burnt through your stock of tubes very quickly.
The Marconi Wireless Installation in R.M.S. Titanic
Titanic's watertight compartments did not reach full height, as one flooded over, the next would begin to fill.
She was going down by the head, not on the level, which meant that evacuation was going to become progressively more difficult and dangerous.
It was a sloppy business from the start.
Titanic's crew poorly trained - if trained at all - in the use of her new and more efficient davits.