Eye bolt in thin plate - what is minimum thickness?
Eye bolt in thin plate - what is minimum thickness?
(OP)
Dear Sirs
Please see attached drawing.

I am going to use a M12 eye bolt DIN 580. And the force is applied parallel to the base plate. You can find specifications on the eye bolts here:
DIN 580 Eye bolt spec
The WLL for the eye bolt is 1700 N, and normally the breaking strength is 5 times higher eg. 8500 N. How thick should the plate be to support the eye bolt? I expect the force to be applied 30 mm above the plate surface. I suspect that the moment applied to the plate is the critical factor.
I should love to know the solution for this specific question and perhaps in more general terms. I suspect, that limits to the moment on a bolt in a plate is a quite common question. However I am no structural engineer, and I have not been able to find the answer here or by google.
Thank you in advance for your help.
Please see attached drawing.

I am going to use a M12 eye bolt DIN 580. And the force is applied parallel to the base plate. You can find specifications on the eye bolts here:
DIN 580 Eye bolt spec
The WLL for the eye bolt is 1700 N, and normally the breaking strength is 5 times higher eg. 8500 N. How thick should the plate be to support the eye bolt? I expect the force to be applied 30 mm above the plate surface. I suspect that the moment applied to the plate is the critical factor.
I should love to know the solution for this specific question and perhaps in more general terms. I suspect, that limits to the moment on a bolt in a plate is a quite common question. However I am no structural engineer, and I have not been able to find the answer here or by google.
Thank you in advance for your help.






RE: Eye bolt in thin plate - what is minimum thickness?
RE: Eye bolt in thin plate - what is minimum thickness?
RE: Eye bolt in thin plate - what is minimum thickness?
RE: Eye bolt in thin plate - what is minimum thickness?
http://www.eng-tips.com/viewthread.cfm?qid=108516
http://msc.aisc.org/globalassets/modern-steel/stee...
Search for "whitmore" in the forums for more posts.
If the plate span is long, you will need to consider buckling from the compression component of the load. Regardless, you need to consider combined bending and axial stresses (P/A + M/Z) over that effective width. Further, bolt bearing will need to be considered. It looks like edge distance is not an issue??
Good luck.
"It is imperative Cunth doesn't get his hands on those codes."
RE: Eye bolt in thin plate - what is minimum thickness?
"It is imperative Cunth doesn't get his hands on those codes."
RE: Eye bolt in thin plate - what is minimum thickness?
“Do not worry about your problems with mathematics, I assure you mine are far greater.” Albert Einstein
RE: Eye bolt in thin plate - what is minimum thickness?
Is permanent bending considered "failure?"
Is visible temporary distortion considered "failure" ?
RE: Eye bolt in thin plate - what is minimum thickness?
I hoped for an easy solution, but apparently this question is more complicated than I anticipated. So I suppose I need a qualified structural engineer for this. I have tried to look for Whitmore, but It did not help me. Please note, that I am not a structural engineer, so I normally only make calculations of simple structural problems.
Tmoose - The loads are dynamic. The maximum dynamic loads is 1250 N, and this might be reached 5 times a week. We are going to make a controlled check once a year up to 2800 N. Typically loads up to 500 N will be applied 200 times a week. And most of the time there is no load. Permanent bending up to 5 degrees should be all right. The loads are mostly from one direction only within 15 deg. I am told, that normal safety factors for this kind of use is 5 times to the limit of elastic deformation.
RE: Eye bolt in thin plate - what is minimum thickness?
what's critical in the sideway loading of eyebolts are the need for shoulders incorporated in the eyebolts and the pulls be in line with the bolt heads as shown in the sketch.
The OP should have stated the thickness of the plates, number of eye bolts used on a plate, spacing configuration between eye bolts.
RE: Eye bolt in thin plate - what is minimum thickness?
You then just provide sufficient structural members to support the given loading back to where ever you are supporting the loads to (I.e. Get a structural engineer involved).
I wouldn't be loading the eyes past the 45 degree case as tempting as it is, the standard has this recommendation for a reason and you cannot infer the same capacity past the 45 degree mark.
RE: Eye bolt in thin plate - what is minimum thickness?
RE: Eye bolt in thin plate - what is minimum thickness?
Elesa-Ganter
Mec-Wolf
Wixroid
Reyher p75 and p148
I cannot go into all details of the application, but in this case it is practical to make use of side load, and 50% load limit is not that bad.
Ron, thanks for the reference to Roark's formulas. Am correct to suggest the formula on page 494, 21b here? Sorry, I cannot link to Roark's formulas because the link has an apostrophe. But google is your friend.
RE: Eye bolt in thin plate - what is minimum thickness?
Mike McCann, PE, SE (WA)
RE: Eye bolt in thin plate - what is minimum thickness?
It would seem to me that you need to spread that load out a lot more - something like the systems below. The second one is mickey mouse, but illustrates the idea I'm getting at.
http://www.liftingsafety.co.uk/product/bolt-on-loa...
https://stretchtents.com.au/products/diamond-pad-e...
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.