Plate thickness and bolt size to support a heavy weight

[RobJCon]

Homework Statement:: If you have a 1" thick steel plate (A36) with a 1.125 hole (supported at 3" half way around), what is the maximum weight that a 1" grade 8 bolt can support using a 2 to 1 safety factor. The weight is applied directly the the bolt
Relevant Equations:: dunno?

it's been 24 years since I've looked at this. any help would be nice.

 

[berkeman]

Welcome to the PF.

Can you say what the application is? Also, can you post a sketch or CAD drawing of the setup? That would be a big help. Thank you.

 

[RobJCon]

I can't. the "bolt" has 30k lbs force pulling straight down on it and I want to see if the 1" plate will support it. it is a weldment.

 

[berkeman]

the "bolt" has 30k lbs force pulling straight down on it

30,000 pounds? That's a pretty big load. What happens if the bolt/plate fail? What does the load fall on?

 

[RobJCon]

that the reason I wanted to know. It falls on machinery and makes a mess.

 

[RobJCon]

it will actually have about 22.5k on it. I just want to try an figure out the force that a 1" plate could hold like that. If 1" is too thin, i'll put 2" or 3". Just trying to get info and explanations and formulas.

 

[berkeman]

I doubt that the Internet is the best place for you to qualify this design. Do you not have professional engineers who help with such designs? What would your work insurance company think about you doing the design based on anonymous feedback on a web discussion forum?

 

[RobJCon]

Well, that is the reason I'm asking for formulas and stuff. If you want to be a butt-head and not help, then don't post. I have understandings about physics and strengths, it's just been 20 + years since i needed them, or used them. Now that being said, ban me, delete this or whatever, All i did was ask a question about a plate thickness in a very generic way so people wouldn't over think the situation. Who is to say that I'm using 1" or 3". I asked the question so that I could get the formulas to calculate the strengths myself and have that as proof needed. Thank you for not answering any question that i asked.

 

[hutchphd]

There are standard formulas and tables for number of bolts required on a gusset (for say a truss for a given tensile load). Should be useful.

 

[RobJCon]

That is not what I'm asking. Double shear and single shear do not apply this. What I'm trying to figure out is the shear strength of the plate with 1 single bolt through 1 single plate. Deflection is not a factor due to bracing and such. I just need the strength of 1 bolt being pulled straight through a plate.

 

[hutchphd]

Then I believe you are talking about tensile strength and probably need to talk to an engineer.

 

[RobJCon]

No, it will be plate shear.

 

[berkeman]

If you want to be a butt-head and not help, then don't post. I have understandings about physics and strengths, it's just been 20 + years since i needed them, or used them. Now that being said, ban me, delete this or whatever,

Well, the Mentors can seem like butt-heads sometimes when they enforce the PF Rules.

Because of the size of the load involved and your lack of experience, this falls under the "Dangerous Discussion" prohibition, and is now locked. Please consult with a local engineer on your question, and be sure to keep your work insurance company in the loop on any design issues that may affect workplace safety and OSHA compliance. Thank you.

From the rules that you agreed to when you joined the PF:

Illegal & Dangerous Activities:
Explicit "how to" discussions of illegal and/or dangerous activities, or posts advocating such activities, are prohibited