The pin anchoring down the chain sees a lot of wear. What design change can be done to prevent wear?

[hungy_kid]

https://imgur.com/0nWiOXi

The chain goes through periodic loading (800 times a day). I don't want to increase the hardness of the pin as I would rather prefer the pin to wear than the chain itself. What I have found so far is that while chain link diameter is 12.1mm, the pin diameter is 10mm. This must be resulting in point loading, so switching to a pin with 12mm diameter, I believe, should help as it would provide more distributed loading. I am looking for effective and cheap solutions. What kind of solution(s) comes to your mind?

 

[r13]

What does the setup look like; what is the load, load directions; what it is for, what is the code/design criteria....I am hungry for information.

 

[EdStainless]

Is corrosion (rust) a part of this?
Is there any dirt (abrasion) involved?
One option would be to use an adapter/clevice of some sort to make the connection.
800 times a day if fairly frequent. How long do these last now?
What is the downside to having a machine shop make you 100 or these at once and then just force them to change on schedule?

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[dik]

any slop in the chain? It might be easier to just lop off one link at a time and use a larger and harder pin...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[Rabbit12]

How often does the pin get to a point where you would need to replace it? Would you need a new pin several times a day or one every few weeks?

 

[BridgeSmith]

Depending on the size and loading, perhaps something with a nylon bushing, similar to a swing hanger, might do the trick. For heavier loads, possibly a greased metal sleeve that's snug in the chain as a bushing?

Rod Smith, P.E., The artist formerly known as HotRod10

 

[dhengr]

Hungy_kid:
This is a Hertz bearing stress problem, and, about the worst condition possible is two cylindrical shapes at right angles to each other, a point loading. And, that’s basically what you have here with the pin and chain wearing on each other. The dia. of the pin and the chain link are not as important as a proper fit btwn. them. BridgeSmith’s idea of a replaceable steel bushing on the pin is a good approach, depending upon the exact dimensions of the pin and the chain link. You want a snug fit on the pin and a slightly tight fit on the inside of the chain link. There are also several types of repair chain links which might be used, and replaced at regular intervals. You really have to give us much more engineering design info about the problem if you want much more. Such as, a dimensioned drawing of the pin and chain link, and material specs. and hardness’, loads; what’s wearing out first and how often, at 800 load cycles per day, etc., etc.

 

[BridgeSmith]

You want a snug fit on the pin and a slightly tight fit on the inside of the chain link.

I would've thought that it would work better if the sleeve was fitted tightly into the chain link, so the sleeve rotates on the pin. A little grease inside the sleeve, and the wear should be down to a minimum.

Rod Smith, P.E., The artist formerly known as HotRod10

 

[dhengr]

Rod:
I agree, the bushing should rotate on the pin, and maybe be something of a press fit into the chain link. But, let’s wait and see his part dims. and sketches, because right now it looks like that bushing is going to have a very thin wall and be almost useless. I believe there are some pear shaped links which might allow a larger bushing which is drilled for the pin and has an outer rim which is hollowed (a concave half round shape on its outer rim) which is made to match/fit the bot. half of the pear shaped link round. I think there are other solutions too, but lets see what he really has first.