Clevis pin

Reece

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So I've been trying to figure out what the shear strength is for a 7/16" clevis pin. The pin that holds the winch hook to the rope.

Has any one ever broke one?

I just find it odd that these are not graded like bolts are. Only thing i could find for sure is that they are low carbon steel(from Fastenal), which might not even get it to grade 2, much less grade 8.

Maybe in a double shear application like this its not as important.
 
You could figure it out, but the whole assembly has a safe working load rating marked on the bow. That load is for a straight pull and no shock load. It should be marked in tons.

I'm not a fan of hooks, and prefer a shackle in that application. Or better yet, a safety shackle.
 
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I had to buy a new clevis pin, thats what got me thinking. So i have no way of knowing its load max now.(I'm not worried just curious)
 
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Calculate it..
http://www.portlandbolt.com/technical/faqs/calculating-strength/

I come up with an estimate of 5150 lbs.

Low carbon steel (like 1018) Ultimate tensile strength is 57250'ish lbs
The cross sectional area of your pin is .150 in^2

so the ultimate strength (strength to break) is 57250 * .150 = 8606 lbs.

Shear is about 60 percent of ultimate (for steel) so 8606 * .60 = 5150

NOTE: This is ultimate strength. You'll start to bend that pin before it breaks....
 
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Calculate it..
http://www.portlandbolt.com/technical/faqs/calculating-strength/

I come up with an estimate of 5150 lbs.

Low carbon steel (like 1018) Ultimate tensile strength is 57250'ish lbs
The cross sectional area of your pin is .150 in^2

so the ultimate strength (strength to break) is 57250 * .150 = 8606 lbs.

Shear is about 60 percent of ultimate (for steel) so 8606 * .60 = 5150

NOTE: This is ultimate strength. You'll start to bend that pin before it breaks....
Thanks, now giving that the pin is in a double shear situation it would put the max load at 10300lbs....

Honestly, that seems a little low when you start mixing in snatch blocks to double up winch power.
 
Calculate it..
http://www.portlandbolt.com/technical/faqs/calculating-strength/

I come up with an estimate of 5150 lbs.

Low carbon steel (like 1018) Ultimate tensile strength is 57250'ish lbs
The cross sectional area of your pin is .150 in^2

so the ultimate strength (strength to break) is 57250 * .150 = 8606 lbs.

Shear is about 60 percent of ultimate (for steel) so 8606 * .60 = 5150

NOTE: This is ultimate strength. You'll start to bend that pin before it breaks....

Very cool calculator, thanks for posting that. I'm having some fun with this.
 
Glad you enjoy it. Just be careful to take it with a grain of salt...there are a lot of assumptions being made there. Those numbers are an approximation.

Oh yeah, I agree. This is the internet though, you've got to take everything with a grain of salt! :p