February 28th, 2006

Malnate, Italy. The load line on a tower crane ruptured which induced a shock load strong enough to separate the turntable. One worker was struck by the line and injured, but by in large, the crane came down in and area that did not have many workers in it.

The jib went over the top of the building and ended up leaving the turntable suspended on the side of the building. The building itself suffered minimal damage and so with the replacement of the crane, only one minor injury, the only real loss was the crane and the confidence of the workers.

Respect for load lines and regular inspections are necessary. I'm a fan of going for a ride in the trolley basket to see the rope on the jib. not only do you get to see all of the line, but you get to hear the sheaves and rollers for their bearing conditions. I'd suggest that you need to inspect the ropes not only visually as many people do, but I would suggest that the right way to do it is tactilely as well. I do this by wrapping an old towel around the line in a safe spot and have the operator hoist it through your hands slowly. Any broken wires grab the old towels immediately and I can't tell you how many times that I've found broken wires on the opposite side of the side I was looking on. The notion that an operator has inspected a line by sitting in the cab and watching it go by is not an accurate or informed position. Certainly it's the most practical as a lone operator up there, but it's not the best that we can do. Get a bag of old used cotton towels that will tear easily. Wrap it around the line so that if it does hang up it won't immediately get dragged into a sheave. Hold on to it in a manner so that if it hangs up it won't tangle in your hand. And position yourself in a manner to be able to communicate clearly with the operator at all times, including by radio if need be. Don't let your load line develop a problem that you never see simply because the breaks are on the opposite side of the line that goes by your line of site.

Link to Original Story
Crollo della gru a torre a Malnate