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Found out the rated load on our old 40 ton is 12 percent less than the sticker says when the jib is out
So I was digging through the original load chart binder for our 2006 unit last week because we were bidding a pick near the river and I wanted to double check something. Turns out the chart on the wall in the cab is the basic one, and there's a separate jib chart in the binder that nobody had ever pulled out. With the 30 foot jib at a 30 foot radius, we lose about 12 percent off the main chart number, which on a 9,800 lb pick is over a thousand pounds. I brought it to my foreman and he just stared at it for a minute because we've run that jib setup plenty of times without thinking twice. We ended up redoing the load calcs and moving the pick closer, everything went fine. My question is, how many of you actually check the jib chart every time or do you just run the main number and eyeball it?
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logan8495h ago
Man, I get why that got your attention, but 12 percent is not the same as everyone assuming the sticker is gospel. Nobody yanks the jib chart out every single pick, and the fact that your foreman had never seen it just means your crew got lucky on the margin, not that every jib pick in the world is a disaster waiting to happen. A 30 foot jib at 30 foot radius is a pretty specific setup, and most of the time people are well inside the chart anyway or they just don't push it. You did the right thing re-running the numbers and moving in, but calling this a widespread problem feels like a stretch.
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