5 ms·
The shackle gets a lot of ink in the media, and it did fail. The questions about who inspected it and how seem a bit misplaced given that it was rated at 120 to
by jws 12y ago
The shackle gets a lot of ink in the media, and it did fail. The questions about who inspected it and how seem a bit misplaced given that it was rated at 120 tons and the tow line alarm registered over 300 tons more than 30 times, so missing provenance or not, it seems like the shackle was performed beyond its design limits and beyond what the engineers required. They were just wrong.
The towline itself was only rated to 85 tons, the towline manufacturer did well.
- radiowave 12y agoTypically, shackles of this sort have a safety factor of 5, meaning that if the maximum working load is 120 tons, the minimum breaking load should be >= 600 tons. Strictly, once the maximum working load has been exceeded, the shackle should be considered compromised. I don't have experience with any shackle on that scale, but my feeling is that you ought to be able to expect a good shackle to withstand 30 pulls to half of its minimum breaking load.