![]() I'd have less concern doing this with a bolt and nut. It's *probably* alright to do with a 9,500 lb strap but I'd be cognizant and careful. 20% of 120 ksi G5 0.31 sq-in in double shear) you have a significant lower and not really defined WLL. ![]() ![]() it deflects but does not bend permanently) you could cause that clip to pop off if it walks, in this case to the right, and is touching the side of the receiver. Even if your load stays within the pin's plastic region (e.g. So it's not ideal but still borderline safe from a numbers game. You have to de-rate a bolted fastener in tension and you lose the purely double shear advantage. In particular it puts the pin in tension. It's never sat well with me because it's loading the pin in an odd way. A 4.75t bow shackle (good to about 47,500 lbs before failure at 5:1 design margin) probably would give up before a grade 8 5/8" bolt in double shear.įrom what I've seen in standards (like SAE) technically a hitch pin should be grade 5.ĭoing this has been suggested for as long as I can remember. Your strap or rope is likely to have broken before a grade 8 bolt in this application. But you would have had to put a force of 46,500 lbs on it just in single shear or 93,000 lbf in the case of a hitch pin in double. So, sure, if you do get a grade 8 bolt to fail and it might shear instead of deform. So IOW, a grade 8 bolt will always tolerate more force than a grade 5 despite their failure modes potentially being different.Īnd the point of all this thinking is to make sure you select hardware that has sufficient strength and margin so that you're never anywhere close to failure points. However the point where a failure like that may occur is higher. It's true, a grade 8 is more likely to fracture or shear than bend like grade 5 might. The key is using a bolt that is long enough that the untheaded shank hits both sides of the receiver so you know the load bearing surfaces are both full 5/8" diameter.ĭidn't think it was appropriate to mention but since you brought it up, there's a minor Internet mistake repeated in the video that grade 8 is worse than grade 5 due to the higher heat treating also increasing brittleness. Click to expand.From what I've seen in standards (like SAE) technically a hitch pin should be grade 5.īut having no uniform standardization or really much way to know or trust one is why some people (who we do trust) recommend using 5/8" bolts.
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