Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Tapped Hole for Lifting Eyebolt - Edge Distance

Tapped Hole for Lifting Eyebolt - Edge Distance

Tapped Hole for Lifting Eyebolt - Edge Distance

Similar questions seem to have been asked in the past but nothing I can find for lifting activities.

We are looking at possibly tapping the outer diameter of some large blind flanges to attach a lifting eyebolt. I'm trying to understand if there is a minimum edge distance between the tapped hole and the faces of the flange?

I've heard rules of thumb but surely there is a requirement for this scenario, especially when we are working with lifting equipment.

Any suggestions as to codes/standards that contain the correct information would be greatly appreciated.


P.S. I understand there could possibly be implications with tapping pressure retaining flanges and I'm dealing with these separately.

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

Hi Morts, this question is better posted in the ASME (Mechanical) Code issues section (or the BPV eng section). Better repost there and red flag this thread for deletion. Also, for a detailed response, it would be good if you provide a little more detail, like flange standard, flange size, pound class rating, service conditions, and a sketch of what youre trying to achieve.

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

Visualizing your plan, it seems that one or more bolt holes would be used to attach one or more eyebolts, is that you plan?

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

How about a dimensioned sketch ?

Tell us about the eyebolt size, diameter and depth of threading

Sr. Process Engineer

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

Since you used the word "flange" it would seem that this could be a round or circular object. If so, then you would need to use three lifting eyebolts. If however your plan is to use either only one or two eyebolts, then you will have less control over the their location since it's going to be critical that you place them so that they're properly positioned relative to the center-of-mass of the object that you're lifting.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

Good starting point would be ASME B30.20 and BTH-1.

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

You should refer to the standard ASME ...,then caculate the distribution of weight of your equipment, to complish your design, such as max lifting load, tensile strenth of lifting bolt and threading,and local stress concentration...

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

Most people think you're trying to lift it in a horizontal orientation, but it sounds to me like you're trying to tap the outer diameter (i.e. through the thickness of the flange)?

Is there a reason you couldn't put a D-shackle through one of the bolt holes in the flange instead, to lift the flange vertically?

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

I think you're looking at hanging this flange vertically so you can get it in position and hold it there while you bolt it up?

I wouldn't go for anything less than 0.5D of the hole you're drilling for the eyebolt.

I'm sure you could look at this in terms of shear of a slot of material trying to detach vertically, but otherwise looks like an FEA job to me.

if the load is truly vertical with a vertical flange face then in theory there is no real limit, just a reduction in load capacity and bending moment available.

You get orifice flanges tapped so maybe look at the requirements of those.

So long as you don't go beyond the bolt circle diameter I don't think you'll interfere with the flange itself, but might want to replace the eyebolt with a plug or bolt to prevent corrosion. Or leave it screwed in.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

With no information given who knows for sure what advice to give. Pictures, drawings, weight, materials, application, etc.

RE: Tapped Hole for Lifting Eyebolt - Edge Distance

LittleInch has it right, perhaps the OP will confirm.



The problem with sloppy work is that the supply FAR EXCEEDS the demand

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close