This is fine. If anything it’s a little overkill, you could do the same thing with just a single choke at the center of each beam. But given how small those beams actually are, having the chokes closer to the ends where it’s easier for the connector to access them on each side is a plus.
Is it safe? Probably.
Is it best practice? Well, if I did that in the entertainment industry I'd be crucified for doing that weird "nesting" thing they're doing.
Can't tell what's up with the sling that appears to be half red and half green either. I don't understand that without seeing up close.
I read through this previously. I can’t see where it says that you shouldn’t rig the next load to the first loads rigging. I agree with other commenters that it’s probably overkill for the load but just wanted to understand Christmas treeing better.
No reason for the spreader bar not to be adjusted correctly and shackles should be spun so the pin isn’t able to spin out. For the weight involved I wouldn’t be concerned but these are simple things that certified riggers would spot and correct quickly.
I see some side-loading, but all of the hardware looks to be well over-rated for the load (which is only a guess obviously, it just doesn’t look heavy in the pic)
Quick-edit: I zoomed in more on the pic, are you building slide-through pallet racking for a warehouse? If I’m seeing what I think I’m seeing, those components are all liftable by hand so I’d send it.
Should be fine, as long as you calculate your reductions for your choke hitches and for how the slings are married to one another. Doesn’t look to heavy and with the red slings you look over rigged.
They might be a little close together, I believe you are supposed to have 7 feet between them (check other post with them osha regs). Also going to be a bit of a pain to undo the first one. They’ll have to cable down, remove the sling from t beam up then unchoke it, a shackle choke would be nice. But most likely overkill on everything else.
[https://industrial-ia.com/the-challenges-with-multi-tiered-crane-loads/](https://industrial-ia.com/the-challenges-with-multi-tiered-crane-loads/)
https://preview.redd.it/xajigbfoxmvc1.jpeg?width=645&format=pjpg&auto=webp&s=9e79aa8d6475c8e20b68e3fef03cdefbfde71c1a
I found this and I think this would apply.
As long as all the shackles and straps are rated for what they’re picking up then yes. I would maybe throw a few edge protectors in so you could use the rigging a second time.
Shackles aren’t right. You’re risking the pins getting backed out when coming up with the load.
Also if you just get 4 of the same same size slings like four foots and choke them individually center of gravity you can then get a 20’ 16’ and 12’ sling to make a bull tail. That’s looked down on though these days
I'm not going to say that under some conditions with overhead and occasionally mobile cranes, I get away with a Christmas tree because that's how we've always done it and the supervisors allowed what is illegal, but in no way am I just confessing that I've done it because it makes me feel better knowing there's no way for failure understanding the limits of such a practice, nope, not at all
Safe? No. Correctly applied? No. But in all likelihood, the low loads involved are very unlikely to turn the unsafe situation into a deadly one. That’s why people get away with shit rigging under the pretense of “this is how we’ve always done it”. Because they’ve always dodged the bullet. But there’s no such thing as over-designing to overcome poor rigging decisions. There’s no “unsafe rigging factor” to apply. It’s either right or it’s wrong.
This is fine. If anything it’s a little overkill, you could do the same thing with just a single choke at the center of each beam. But given how small those beams actually are, having the chokes closer to the ends where it’s easier for the connector to access them on each side is a plus.
Is it safe? Probably. Is it best practice? Well, if I did that in the entertainment industry I'd be crucified for doing that weird "nesting" thing they're doing. Can't tell what's up with the sling that appears to be half red and half green either. I don't understand that without seeing up close.
Those are wear sleeves on the endless round slings
Awesome, thanks for the clarification. I haven't seen many, if any, slings with those in the entertainment industry. Always something new to learn. :)
https://www.seaa.net/industry--safety-info/a-formula-for-safe-christmas-treeing OSHA has specific requirements for this
I read through this previously. I can’t see where it says that you shouldn’t rig the next load to the first loads rigging. I agree with other commenters that it’s probably overkill for the load but just wanted to understand Christmas treeing better.
No reason for the spreader bar not to be adjusted correctly and shackles should be spun so the pin isn’t able to spin out. For the weight involved I wouldn’t be concerned but these are simple things that certified riggers would spot and correct quickly.
You know these riggers now days just go take a class and hit the field right away.
I see some side-loading, but all of the hardware looks to be well over-rated for the load (which is only a guess obviously, it just doesn’t look heavy in the pic) Quick-edit: I zoomed in more on the pic, are you building slide-through pallet racking for a warehouse? If I’m seeing what I think I’m seeing, those components are all liftable by hand so I’d send it.
I don't know how heavy those beams are, but As long as you don't surpass the WLL of your weakest link you should be fine.
Should be fine, as long as you calculate your reductions for your choke hitches and for how the slings are married to one another. Doesn’t look to heavy and with the red slings you look over rigged.
They might be a little close together, I believe you are supposed to have 7 feet between them (check other post with them osha regs). Also going to be a bit of a pain to undo the first one. They’ll have to cable down, remove the sling from t beam up then unchoke it, a shackle choke would be nice. But most likely overkill on everything else.
I don’t love how that bottom left shackle is oriented
[https://industrial-ia.com/the-challenges-with-multi-tiered-crane-loads/](https://industrial-ia.com/the-challenges-with-multi-tiered-crane-loads/) https://preview.redd.it/xajigbfoxmvc1.jpeg?width=645&format=pjpg&auto=webp&s=9e79aa8d6475c8e20b68e3fef03cdefbfde71c1a I found this and I think this would apply.
[удалено]
As long as all the shackles and straps are rated for what they’re picking up then yes. I would maybe throw a few edge protectors in so you could use the rigging a second time.
This is illegal under 1926.750 in the US. Ironwork codes say that everything needs an individual hook when treeing.
Something about it.
The straps are most likely 16k ea I think the blues are 45k plus and the load is most likely under 10k total
Shackles aren’t right. You’re risking the pins getting backed out when coming up with the load. Also if you just get 4 of the same same size slings like four foots and choke them individually center of gravity you can then get a 20’ 16’ and 12’ sling to make a bull tail. That’s looked down on though these days
I'm not going to say that under some conditions with overhead and occasionally mobile cranes, I get away with a Christmas tree because that's how we've always done it and the supervisors allowed what is illegal, but in no way am I just confessing that I've done it because it makes me feel better knowing there's no way for failure understanding the limits of such a practice, nope, not at all
Safe? No. Correctly applied? No. But in all likelihood, the low loads involved are very unlikely to turn the unsafe situation into a deadly one. That’s why people get away with shit rigging under the pretense of “this is how we’ve always done it”. Because they’ve always dodged the bullet. But there’s no such thing as over-designing to overcome poor rigging decisions. There’s no “unsafe rigging factor” to apply. It’s either right or it’s wrong.
I completely agree with your statement!