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soopaman2 · 10-11-11, 05:04 PM

Here is some copypasta from wikipedia on liberty ships.

Early Liberty ships suffered hull and deck cracks, and a few were lost to such structural defects. During World War II, there were nearly 1,500 instances of significant brittle fractures. Twelve ships, including three of the 2,710 Liberties built, broke in half without warning, including the SS John P. Gaines,[5][6] which sank on 24 November 1943 with the loss of 10 lives. Suspicion fell on the shipyards which had often used inexperienced workers and new welding techniques to produce large numbers of ships in great haste.[7] The Ministry of War Transport lent the British-built Empire Duke for testing purposes.[8] Constance Tipper of Cambridge University demonstrated that the fractures were not initiated by welding, but instead by the grade of steel used which suffered from embrittlement.[7] She discovered that the ships in the North Atlantic were exposed to temperatures that could fall below a critical point when the mechanism of failure changed from ductile to brittle, and thus the hull could fracture rather easily. The predominantly welded (as opposed to riveted) hull construction then allowed cracks to run for large distances unimpeded. One common type of crack nucleated at the square corner of a hatch which coincided with a welded seam, both the corner and the weld acting as stress concentrators. Furthermore, the ships were frequently grossly overloaded and some of the problems occurred during or after severe storms at sea that would have placed any ship at risk. Various reinforcements were applied to the Liberty ships to arrest the crack problems, and the successor design, the Victory ship, was stronger and less stiff to better deal with fatigue.
Several designs of mass-produced petroleum tankers were also produced, the most numerous being the T2 tanker series, with about 490 built between 1942 and the end of 1945.

In high seas they would literally crack down the middle, and forget it if a torpedo lifted them up.
They were more "spammed" than designed.
I remember seeing something about the man (Kaiser) who built a good majority of them, and how he had to mount reinforcing straps across the length of both sides of the ship (I watch military channel alot)

10-11-11, 05:04 PM	#11
soopaman2 Der Alte Join Date: Sep 2011 Location: New Jersey, USA Posts: 3,316 Downloads: 61 Uploads: 0	Here is some copypasta from wikipedia on liberty ships. Early Liberty ships suffered hull and deck cracks, and a few were lost to such structural defects. During World War II, there were nearly 1,500 instances of significant brittle fractures. Twelve ships, including three of the 2,710 Liberties built, broke in half without warning, including the SS John P. Gaines,[5][6] which sank on 24 November 1943 with the loss of 10 lives. Suspicion fell on the shipyards which had often used inexperienced workers and new welding techniques to produce large numbers of ships in great haste.[7] The Ministry of War Transport lent the British-built Empire Duke for testing purposes.[8] Constance Tipper of Cambridge University demonstrated that the fractures were not initiated by welding, but instead by the grade of steel used which suffered from embrittlement.[7] She discovered that the ships in the North Atlantic were exposed to temperatures that could fall below a critical point when the mechanism of failure changed from ductile to brittle, and thus the hull could fracture rather easily. The predominantly welded (as opposed to riveted) hull construction then allowed cracks to run for large distances unimpeded. One common type of crack nucleated at the square corner of a hatch which coincided with a welded seam, both the corner and the weld acting as stress concentrators. Furthermore, the ships were frequently grossly overloaded and some of the problems occurred during or after severe storms at sea that would have placed any ship at risk. Various reinforcements were applied to the Liberty ships to arrest the crack problems, and the successor design, the Victory ship, was stronger and less stiff to better deal with fatigue. Several designs of mass-produced petroleum tankers were also produced, the most numerous being the T2 tanker series, with about 490 built between 1942 and the end of 1945. In high seas they would literally crack down the middle, and forget it if a torpedo lifted them up. They were more "spammed" than designed. I remember seeing something about the man (Kaiser) who built a good majority of them, and how he had to mount reinforcing straps across the length of both sides of the ship (I watch military channel alot) __________________ If Hitler invaded Hell I would make at least a favourable reference to the devil in the House of Commons. -Winston Churchill- The most fascinating man in the world.