pinned joint design

[CondensedMatter]

Anyone know of good resource(s) for pinned joint design in a linkage:

1. Pin sizing
2. Lug sizing
3. Bushing sizing / material
4. Typical pinned joint designs (cross sections)

Everything is alloy steel except the bushing. All pins are double shear. Environment is slightly corrosive, so parts will likely be coated and galvanic couples minimized.

I've already looked at V/A and VQ/It, and want a "3rd opinion". My main qualm with VQ/It is it assumes uniform stress distribution over the thickness t.

Radial load estimations already have been done.

Any resource direction would be helpful!

 

[wes616]

I am confused by your question. Are you looking for suggestions on parts manufacturers, or are you looking for help with the stress analysis?

Wes C.
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No trees were killed in the sending of this message, but a large number of electrons were terribly inconvenienced.

 

[CondensedMatter]

yes.

 

[rb1957]

Bruhn, Michael Niu, ...

I think you're right (that VQ/It isn't appropriate to a lug)

 

[wes616]

vQ/It is for transverse shear in a beam type model. Unless your lingage is loosly linked (ie, there is out of plane movement allowed due to a loose fit) there should be negligible bending on the pin. It seems to me that it is appropriate to size components for the following considerations.

1. double shear (V/2A)
2. tear out on the bearing area of the linkage
3. pin bearing.

Without knowing what your particular senario, I could not tell you wich failure will be most likely, but it will typically fail in one of these three senarios.





Wes C.
------------------------------
No trees were killed in the sending of this message, but a large number of electrons were terribly inconvenienced.

 

[A514]

Condense,
4140 steel is a great material choice for the pins.
Pin Shear4/3) Force/Area Use allowable safety factor
Lug Sizing Force/Bearing Area
Bearing Area=Pin Diameter x Metal Thickness
Bushing Sizing=Press Fit into hole, Material of Choice 8620 steel case hardened to 60-65 R.C.
I hope this helps

 

[CondensedMatter]

A514,

Thanks!

I'm going from memory, but I think I derived shear stress = 4P/3A out of VQ/It for a round pin.

Thanks everyone for your input.

 

[kenvlach]

What about the corrosion & coating aspects?