Temporary Support Beam - Rigging and Transportation

[LSPSCAT]

Project involves design and fabrication of support beam to provide temporary shoring of heavy equipment during a rigging and placement operation. As is often the case in heavy rigging the support beam will span across blocking. Any concerns regarding stability of the blocking? I am required to provide a stamped design of the support beam; however, my role does not necessarily extend to the final use. Any concerns with stamping design where final end use is not provided?

I previously worked in heavy rigging and many times steel "stools" were used to support loads. Many times the rigging drawings were required to be stamped and that drawing would include temporary support means on "stools" or blocking and I do not recall if any specific consideration was given to require the "stools" to be restrained.

Maybe a case of too much knowledge and details clouding my thinking. It is an OSHA violation to not have your tool stands bolted to the floor. (Vise,Grinder) What are the requirements for temporary rigging supports?

 

[CANPRO]

If you don’t have control over the end use then I would be very clear about that on the drawing.

When I’m in a similar situation to yours, I do the following:

Do my best to understand the end use so my design gives the final user the best chance at success.

Clearly state on the drawings my assumptions and unknowns.

Where my design interacts with unknowns, I show just enough information to ensure my intent and design requirements are met...but beyond that I keep the “unknown requirements” fairly general so it allows flexibility on site and keeps the responsibility with the end user (and I make that very clear as well).

In your specific case I would probably show generic blocking in the location you require it (or allowable locations), show min bearing requirements for your portion of the design, and I’d add a note saying something along the lines of “contractor to provide blocking to suit site conditions. Reaction on blocking is xx lbs. design of blocking is the responsibility of the contractor. Blocking to be designed and installed per OSHA and (any code/requirement)”. Any further involvement than that is a different conversation which has more questions and requires more info.

 

[JStephen]

Theoretically, it's perfectly okay to design a beam for certain specific loads and support conditions, indicate all those loads and required support conditions on a drawing and stamp the thing.

In practice, you tend to wind up with people that have the beam and don't have the drawing, or have the drawing but don't read the notes, or they read the notes, but don't have ability to do the additional analysis required, etc., which makes it not so desirable to use that approach.

 

[Lomarandil]

Depending on the situation, blocking stability may be OK by inspection, but you're not wrong to consider it.

I'd follow CANPRO's advice and perhaps make a phone call to the end user if possible.

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The name is a long story -- just call me Lo.

 

[LSPSCAT]

Thanks for the helpful discussion. I agree, I typically handle the same way with rigging arrangements and spreader bars. Provide general arrangements, required rigging arrangement, and notes describing intended use and limitations. Those products may very well be used for the next 20 years and much of that original information will be long forgotten.

I agree, that typically things like blocking or temporary support are approved by inspection. I have been on-site for heavy lifts and certain things need to be signed off to progress to the next steps and it is performed by inspection.

I did just have the occasion to perform some work for a manufacturing plant and we were going through OSHA specs for guarding and machinery mounting and it just starts getting your mind going. Paralysis of analysis I suppose, mind starts to wander and before you know it there are more questions than answers.