Elements of a Lifting Plan 2

[kylesito]

I'm putting together some lifting plans for a client for a few steel assemblies we have designed for them.

What elements make up a good lifting plan? So far I have:

location of pick points
weight of assemblies
weight of rigging
allowable angle range for slings
spreader beam and lifting lug details

The actual design of the rigging (slings, hooks, shackles, etc) will be done by someone else.

Thanks for all your help.

PE, SE
Eastern United States

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi

 

[TheLinker]

The spreader beam may require it's load rating to be displayed, this is per OSHA I believe.

Also, Who will be responsable for the stability of the lifting rig during the pick? and determining the base reactions at the support locations?

If the rig is on a concrete slab or other, that would need to be looked for the reactions during the lift.

 

[dhengr]

Kylesito:
Since you designed the steel assemblies, you should also design, locate and weld the lifting lugs, pad eyes, lifting points, doubler plates, etc. to protect your own fabrication. You know your fabrication better than anyone else, and you don’t want them messing it up with their half baked lifting ideas or welding. A lifting hole or point could be as simple as hole in a flange or web, with doubler pls. if needed. Given the load at that point, selects a min. size shackle for you. But, make all the holes to fit the largest shackle needed, so they don’t need four different shackle sizes. You should know the weight and C.G. of your fabrication and show those on a drawing, in all three orientations. Obviously, you should have a vague idea how the piece might be lifted, or how it should not be lifted.

If they can throw a chain or sling around it and lift away, weld a stop lug on the structure, at a location of your liking, so the chain can’t slip. Maybe note that they should protect the edges from the chain or sling. If you design lifting lugs and locate them where you want them, show a max. vert. lifting load and the shear loading on that lug and let them go at it. They should be able to do the math btwn. your lug specs. and their lifting equipment. You don’t know anything about the rigging so how can you say anything about the rigging weights, lifting sling angles or spreader beam details. Those are the riggers responsibilities, and dependant on his equipment, the crane size, etc. If your structure will only take a vert. load at a given lifting lug, your sketch would show a vert. max. cap’y. and zero lateral/shear loading. To that extent you can direct the rigger in how he treats your fabrication. This info. can be shown on a cleaned-up arrangement drawing of the piece in question, along with some basic lifting and rigging directions.... comply with OSHA, ASME Below the Hook specs., etc. You should assume the responsibility of protecting your own fabrication, but don’t assume the rigger’s responsibility by telling him what to do.

 

[kylesito]

Good information from you guys thanks.

I had the lifting lugs on the assemblies themselves taken care of. However, I didn't realize OSHA requires the capacity of the spreader beam to be stamped directly on its side. That's a good detail to make sure I include!


PE, SE
Eastern United States

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi

 

[Hoaokapohaku]

The attached file is a lift plan that was used for an extreme high value (>$80,000,000) piece of optical equipment for the upgrade of a high tech astronomical telescope. Sketches of the item showing pick points and rigging to be used were attached, as well as the certification documentation for all equipment, rigging, operators, riggers, etc.

Normally lift plans are lift specific and do not include things required by code and required for any lift. For instance, the lift plan would not normally say any thing about the fact that the rated capacity of a lift beam must be clearly marked on the beam. That is just one of many requirements for a lift beam that is required by code. Rather, inspection records and certifications are submitted demonstrating compliance with all code requirements.

 

[Teguci]

@Hoaokapohaku - Very thorough, thanks!

Need to add site develoment requirements to the list. This includes marking out underground hazards and supplemnting the crane pad with crush stone or cribbing.

Also add responsibility list identifying key characters.

 

[Hoaokapohaku]

I failed to mention one other very important thing that should be attached to the lift plan, - a copy of the crane's load chart for the intended configuration. The lift plan includes the radius and weight of load and rigging. By including the lift chart anyone can check and see that the load as planned is within the limits of the crane's safe working capacity.

 

[kylesito]

Hoa and Teguci...very good information and very thorough responses to my question, thank you.


PE, SE
Eastern United States

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi

 

[stanweld]

In addition to the above, crane size/type/capacity, crane location/footprint, ground stabilization required for crane at full load, crane boom height and radius of movement defined in drawings with obstructions depicted.

 

[w12x40]

If you aren't specifying and designing the crane and rigging, don't make any mention of it. Otherwise, you'll end up on conference calls discussing whether your specifications allow this other crane, that leftover wire rope from the other job and how to bridge over the rain water conductor that just CAN'T be moved. Unless you've been specifically hired to create a crane plan, you should only be specifying a few things beyond your lifting lugs:

1. Are they required to use a spreader bar? Saying "yes" makes your math easier with no compression in the assemblies.
2. If they aren't (most contractors don't want to rent or fabricate a spreader bar) tell them what angle sling you want. ASME B30.9 (Slings) gives convenient charts for slings at 60, 45 and 30, so I'd design for one of those.
3. Specify the size pin you need to go through your lifting lug for bearing or tearout. This will translate to the size shackle they need, so check a Crosby catalog to make sure the pin size you pick goes with a shackle that has the minimum working load limit (WLL).
4. Service reactions at the lifting lugs so they know how to size their rigging and crane.

Design your lifting lugs using ASME BTH-1 (Design of Below-the-Hook Lifting Devices). It gives specific factors of safety for lugs and connections, plus a good guide for lugs.