Hilman Roller on Aluminum Flat

[jmen68]

I have an application were it would be beneficial to use an aluminum (6061-t6) channel or plate (has to be manhandled) to use as my rolling surface for a loaded hilman roller. I am using a Hilman roller model 20-OT that has 5 contact rollers that are 4" long X 1.18" OD. My load is 39.5 kips per roller. The rolling surface will be completely supported by a concrete foundation, no strength issues there, my concern is I want to know if the rollers will make any permanent indention on the channel/plate. I feel like this should be figure-able using a liner line load and the hardness of the material but I don't know what formula to use or where to even find this out? My only experience with hardness in my civil eng. career was in school using a direct readout of a Brinell hardness tester, push he ball and read the number, at least thats all I remember. I the load should equate out to about 2,000 lbs / linear inch. 6061-T6 should be about a 95 on the Brinell chart per this site Anyone have a direction to point me? thanks.

 

[MJCronin]

Contact Stress evaluation is an area that is more "machine design" than structural engineering...

https://www.amazon.com/gp/product/0...61&tag=ameswebinfo-20&linkId=F7DBT2FPW54RGYMD

What did the people at Hillman Roller tell you when you called them ?

https://www.amesweb.info/HertzianContact/HertzianContact.aspx

Please explain why a hard and tough stainless steel cannot be used. "Because the client told me so" is not an acceptable answer ...

Are you familiar with the Roark "Formulas for Stress ans Strain" text ?..... There are many contact stress cases contained therein ...


MJCronin
Sr. Process Engineer

 

[btrueblood]

Why not just roll directly on the concrete surface?

 

[jmen68]

Hilman said Aluminum isn't acceptable, no other reason.

I have to man handle all these pieces, I wanted aluminum to save weight. S/S is out because its heavier then C/S.

I have Roark, never used it, think table 14.1.2 is the right spot? I am still unsure if I can do the equation with any certainty thought.

Rolling on the concrete would probably destroy the rollers, as I will be repeating this many many times. And it would greatly increase the rolling friction and force needed to push the load.

 

[EdStainless]

SS and CS plates weigh the same, for long term use people often prefer SS because they don't have to worry about the surfaces rusting.
Al has two problems, first fairly low strength, but secondly and more important is the low modulus.
Use SS plates, provide handles for easier use and keep them only as large as you need.

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P.E. Metallurgy, Plymouth Tube

 

[racookpe1978]

Your problem with Al plates is going to be increased because the Hillman rollers will compress into the Al surface making a long slot the same OD as the roller. Then, when the assembly is "pushed" (pulled) the roller must roll up out of that embedded "ditch" to start, but continues to "roll uphill" the rest of the trip.

So you need to obtain a hard enough surface sufficient to spread the roller tangent point load out enough to NOT embed into the Al support. Now, a liner or thin Stainless plate on top iof the Al might work, but has to be fastened to the Al base to prevent any sliding movement under friction loads, and thick enough so the force is spread out enough before it hits the Al base.

 

[jmen68]

@RACOOKPE1978 My man, that is what I am trying to figure out, if the aluminum is hard enough and can be substituted.

 

[3DDave]

Why try to figure this out? Just buy some aluminum and see if it works. If it does then fine. If it doesn't then you are out the cost of aluminum and with no alternative. Win-win.