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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."
Running time: 194 min.
If only it had gone down faster.
Since the mid-90's there have been tons of BBC and Discovery Science and History channel specials on the Titanic and they ALL said the same thing, the shipyard used substandard metals in the rivett's to cut back on the cost of building the ship. And these same history shows all said the same thing, to much slag found in the rivets causing them to be extremely week and would pop with minimal, for its size, force.
I remember in a Discovery Channel special about the Titanic they mentioned that the plates were torn apart at the seams rather than gashed through by the ice. The amount of force with which the ship hit the ice was low enough that it should not have ruptured.
So many years later, I wonder if it is worth it to hold the shipmaker accountable for the tragic loss of life. The stowaways in the galley climbing the railing at the bow shouting their claims to the throne of the earth were all taken under, and though they found love in the last hours of the Titanic, I can't help but wonder what sort of lives such rapscallions would have lived had they landed in New York City. Instead, at the bottom of the sea is the blue gem, shining brightly in the ghostly beams of the research submarines, so far away from the hands which let it fall to the seafloor in remembrance of the short, brilliant, flash of love in those few hours whose imprint upon Rose lasted her whole life.
"Given the microstructure that we've seen, our best guess is that the rivets failed before the steel plates cracked, and the seams between plates simply opened up," Weihs says.
-- Johns Hopkins University Gazette, 26 April 1999
Except in the version I saw the Titanic looked like a giant hot dog running aground in a sea of ketchup. Also, LSD was involved.
Because the Titanic was labeled as "the best thing since sliced bread" and went out of it's way to seem grand and impressive. Then it sunk on it's first voyage and proved that even the grandest of things are but a paper weight should you have no luck. It is the ultimate in luxury and a bad luck story rolled into one, so people find it fasinating.
I like muppets.
If not for the weak rivets, we wouldn't have gotten to see Leonardo DiCaprio drown.
Why is the ship-builder hesitating to claim such progress?
There are several reasons why:
1. Schadenfraude: the immense hubris of the builders and operators of the Titanic were key factors in the loss of the ship. Stories where supreme arrogance is dealt a blow by nature are always fascinating to people.
2. A grand supposedly unsinkable ship sinking on her first voyage.
3. This accident prompted a sea change (pun intended) in maritime safety practices.
From an accident investigation standpoint, it is also the classic demonstrator of the accident chain. Many maritime and aviation accidents consist of a long chain of direct events that occur over a considerable period of time, and if any of the links been broken, the accident wouldn't have occurred.
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"Silly boy. Iran doesn't have ice!"
All the more reason to attack them now, if they get their hands on ice making technology we are sunk! Better use nukes to make sure we melt any secret bergs they have hidden in the desert.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Even if the rivets had been perfect it would still have sunk. The design was such that once a big enough hole was made, i.e. weren't enough pumps to keep the water level down, the water filled to above the bulkheads and swamped the next cell, and onto the next. It was a poor design when faced with the accident it had. IIRC the ships designer was on board and once he was told the size of the hole he was able to tell the captain how long it would take to sink.
threadeds blog
Ship building in early and mid WW2 was a race to make ships faster than the U-boats could sink them. Keep trading quality for quantity until the number that sink on their own approaches the number that the enemy sinks for you, and you have hit the right tradeoff.
I wonder how many of those ships made in the early supply of Britain survived more than a couple crossings before soaking up a torpedo? Need to find some statistics on how many ships simply sank due to defect vs attack.
I work for the Department of Redundancy Department.
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.