Hi,

I have a 15k forklift that needs a pin for towing a 35,000 lb test skid (short distances in our lot). The pin that goes through the tow bar is bent and keeps getting stuck in the hole.

What I'm looking for is a good, bend-resistant steel bar stock, 1.375 inch dia. I am afraid that tool steel may be too brittle, especially in the cold environment we work in (far Northern NY State).

Does anyone have any recommendations? Any help would be greatly appreciated! Thanks.

Todd

4140 normalized would work I expect. Has a lot of toughness, some rust resistance (compared to 10xx), and you don't need hardness.

Why not order one through the local forklift service place?
Phil

"Bend resistant" usually means "flexural yield strenght exceeds demand of application." In your case it means a flexural yield strength exceeding 23.6ksi. "Exceeds" usually means by a factor of two, for safety. Any plain-carbon cold-rolled steel would do the deed. So would most hot-rolled low-alloy steels.

What kind of steel are you using now?

Why not just straighten the bent pin, I've had to do it on several pins and have even used heat and not had a problem with it.

welder19

Just gotta ask, Why are you pulling a 35K skid with a 15K truck? If I had to do it I would wrap a chain around the counter weight.
Ken

G;day the quickest way ( my thoughts only ) and easyest would be a high tensile bolt and you can buy them of the shelf
cheers John

Let me see if I have this right. You are pulling 35,000 lbs with a forklift rated for 15,000 lbs lifting. You have a pin that is 1 and 3/8" in diameter. And it got bent?
I am not being wise, but a little more info might be needed here. Like: How did the pin you already have get bent? Why can't you order or buy one from the/a forklift manufacturer, dealer/ distributor, repair/maintenance? If you get one from a reputable source (not saying you are foolish or anything) if anything goes wrong, and someone gets killed or injured, then you are not responsible or more importantly legally liable!!!

I would stay away from the bolt idea. Not that it wouldn't work, just that bolts are made to have tension on them end to end, and not shear at the holes under the proper torque. They tend to bend in the middle when subjected to a load in the middle with the ends supported.

Just my opinion, take it or not.. be safe
Cliff

CBrann has good points. First check to see what the fork-lift is rated for. If you are exceeding what the equipment is designed for, then likely something will give at some point when its capacity is exceeded. I've pulled a mower at the back of a farm tractor that had shear-bolts. Sure it was a pain to replace the bolts, but those bolts were designed to shear rather than allowing more expensive parts to fail from exceeding their capacity, or to cause some catastrophic failure that would injure the operator.

Quality furniture was/is designed that way too. Good furniture was designed to come apart where they could be easily repaired after being overstressed. This was a the joints. If modern super-strong adhesives are then used to repair these old pieces, then the next time they break will not be at the repairable joints but where the repair will be much more difficult, expensive and much more obvious.

Will one of the pins used for RR car couplers fit? It should be rated for tough duty in a similar use case.

This would be a saftey concern to me.

I'm not just trying to be negative here, but if I were dealing with that kind of weight, I'm not sure I would use anything except what I know is intended to do it. If you use something that is not up to the task and it fails, it could shatter and send schrapanel somewhere you might wish it hadn't. The proper pin can't cost more than a visit to an emergency room. If the pin you are using is designed for the piece of equipment you are using, maybe you need to be revisiting how you are moving stuff around.

maybe you need to "bush" up the the hitch so it dosen't have the room to bend...just a thought,good luck, jimmy

Will one of the pins used for RR car couplers fit? It should be rated for tough duty in a similar use case.

The load in a railway coupler is not on the pin. The hole on the coupler is actually SLIGHTLY oval so that when tension is placed on the coupler the load goes to the pulling lugs not the pin.

You can buy 4140 prehardened, it is tough hard not brittle hard.

I think I would just go to the local farm store or tractor dealer and get a pin the correct size. They are made for the purpose, and aren't too expensive. Why re-invent the wheel, so to speak.

Thanks Phil. Simple answer for a simple question. :)

Thanks to all for your concerns, but we have our reasons for not using other sources (retail=$$), and are limited in what equipment we have to complete our tasks. "Ya gotta do whatcha gotta do" to get the job done with limited resources. :)

A pin from a trencher chain will do for what you are doing .

Sam

you are correct... higher alloy steel can be brittle in cold environments (loss of toughness) you can see this on impact tests.... add abit of Ni to help with that

Thanks Phil. Simple answer for a simple question. :)

Thanks to all for your concerns, but we have our reasons for not using other sources (retail=$$), and are limited in what equipment we have to complete our tasks. "Ya gotta do whatcha gotta do" to get the job done with limited resources. :)

There is no Good Reason to do something Stupid. Why don't we start by putting a price on a human life, then if the cost of doing it right is more than the price of a life, we can go ahead and put someone at risk, if the cost of doing it right is less than the price of the human life, then we will go ahead and protect the individual.