Big Loads - Post Photos Number 2

81 feet long and 82k. The one I have now is 93 feet long and weighs about the same because it's thinner.

 

Well spent 8 hours today unloading 4 trucks... That is how it goes with bridge beams because they have to move so slow when moving them, especially when the cranes are near the max lifting capacity. They even had the warning chimes playing in stereo today.... LOL

 

I'm curious, does anyone know, when they use 2 cranes to lift one object, how do they determine how much weight capacity to assign each crane?

If one crane gives out, that's a lot of weight solely on the other crane.

 

Twin crane lift are done regularly for long item and heavy items. Complex lift plans are usually draw up as cranes shouldn't be at there maximum capacity. You can roll the cranes over just by not having a straight lift by one crane pushing on the other.

 

Pipe 40 has it right on. We did one this spring in Yellowstone park where they used a single crane because the pieces were only 36k each and only about 36 feet long. But even at that they had to bring in a 550 ton crane to handle the project. The bridge was 173 feet long and they had to set it from one end. The other end of the bridge had high density foam under the road because of thermal activity. A crane would have crushed that foam. It had to be that big of a crane because of the reach that was needed. I have seen an 80 ton crane with one set of outriggers a foot off the ground while setting a 65k bridge beam because of reaching too far.

As for assigning the weight to each crane, for these beams it was 45k each but they also have to be good operators. If one lifts their end higher than the other it can put too much weight on the opposite crane. Same is true if they do not lift as high as the other, they will be the one with too much weight.

Mainly because of the reach required, two cranes are needed.

These were the beams for Yellowstone....



And this was the bridge they were setting....

 

Mac, if you ever get the chance to go on a big construction project, or a wind farm, or a rig move...it will amaze you. The drivers, the riggers, the fork ( I dont know what it's called, but its that offroad forklift thing with the boom forks, that brings the crane pads and the big dunnage) the crane operator all working together. If theres a good crew working, those twin cranes can really accomplish alot!

One of the most impressive things I've seen was in SLC. I had been part of a Mamoet hydraulic trailer move. Well, they put this thing together, and then picked up a bridge that was going over both sides of I-15 south of SLC, put it on a trailer, secured it, and took it away. That was one biiiiiiiiiiiig freakin load. The piece I loaded had 12 axles, all hydraulic, and weighed 60000. So, its 2 portable cranes, putting together a set of big Manitowocs.
I bet there were probably 100 trucks involved.

 

There is 3 episodes of a British show on YouTube call Crane Gang, well worth a look if anyone likes cranes the best bit IMO was the 600t+ track crane sitting on a dock lifting a huge cable reel on to a barge not room for error

 

Telehandler

 

We always called it a "zoom boom"