Sunday, April 26, 2009

April 26th, 2009


The initial reports on the cause of the Taipei accident is overload and weather. The crane was rated for 3.2 tons at the working radius and the load picked was 4 tons. Additionally it was windy during the lift. Wind loading is all too often neglected. The most common number for maximum wind loads on tower cranes is 70 kph or 42 mph. You need to heed the manual in the crane. Pressure to make picks has killed before, it will kill again, just don't let it be on your crane. The most famous case of wind overloading is the Big Blue Crash at Miller Park in Milwauke that killed 4 Ironworkers.
Why is it that this crane didn't have it's load limits set as well? I always thought that was the beauty of being a tower crane operator. The crane can make the pick or it can't, period. There is no turning of the key and puching the limits into your safety factors.

In Singapore the collapsed luffer has been safely dismantled. A 800 and 600 ton crane was brought in and operated for 22 hours to get the crane down. Anyone who has been involved with a fallen tower crane can tell you that it's a delicate operation to dismantle it. Pick points are not what you would always hope and you are torching metal apart and uncertain of weights. I don't envy that work and applaud their ability to get the crane safely apart in mid air.

The openess of the recent accidents is refreshing and helps us all as good reminders to use proper and prudent practices.

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