How can this part be manufactured? 10

[sampsonr]

Hi There,

I'm looking at getting this part manufactured out of copper which has internal cooling chambers. It needs to be made from 1 piece and needs to be water tight. Does anyone know of a process that can produce this?

Approximate dimensions are 500mm x 60mm x 25mm

Ideally I would like to cast it but the only process I've come up with so far be a sintering process such as sls.

Any help would be greatly appreciated.

Cheers,
Roy.

 

[msquared48]

Man I hate it when I miss the details...

Mike McCann
MMC Engineering

 

[MikeHalloran]

Yes, KENAT, it is a heat transfer problem.

{
I'm under the impression that the project, and the material selection, is being steered by some pushy, arrogant, dumbass MBA type, who looked no farther than a table of thermal conductivity numbers. ... as has happened to me on occasion. ... not that I'm bitter about it.
}

If you trouble yourself to run the numbers for the whole problem, you will find that the contribution to the total thermal gradient of a thin metallic barrier is completely dwarfed by the contribution of the boundary layer or laminar sublayer on the fluid side, and by the thermal resistance of the joint between the cooling module and whatever is being cooled on the hot side.

Whether the thin metallic barrier is copper, or brass, or nickel, or aluminum, or even steel, hardly matters in the real world, and is small enough to be difficult to measure if you wish to bother with a proper experiment.



Mike Halloran
Pembroke Pines, FL, USA

 

[sampsonr]

Fortunately no pushy MBA types are driving this project only me who is doing this as a side line project at home. I am mechanical design engineer who designs automated production lines by trade with very little experience in thermodynamics but the more I work through the calculations the more I realize the material choice is minor compared with how the fluid actually conducts within itself and onto the exchange face. That must be why so many heat exchanges are made out of stainless steel rather than aluminium and copper.

Would this part be any easier to produce if it was made out of stainless steel, aluminium, bronze or brass?

Cheers for the input!!
Roy.

 

[BrianPetersen]

The part would be easier to produce if you go back to functional requirements and redesign it to be a different shape.

If this is immersed in another fluid, turn the bends 90 degrees. Piece of tube running the length, bend 180 and run the full length back, bend 180 and run the full length forward again. If needed, crimp end plates on to hold the tubes in shape and allow you to attach the gizmo to something else. If the other fluid that it is immersed in is air, you are going to need fins.

Google ... "images" ... "power steering cooler". Something like that.

 

[MikeHalloran]

One piece with no seams is a bitch in any material but less so in copper or nickel. Hugely expensive regardless.

If you allow a seam the cost is in machining the channels, so brass would be least awful.

Most producible is probably a serpentine copper tube cast into a block of aluminum.

Corrosion resistance will affect the selection.



Mike Halloran
Pembroke Pines, FL, USA

 

[MintJulep]

Make an outer case out of copper sheet, stainless sheet, aluminum sheet or whatever.

Make a serpentine pipe out of copper tube.

Put pipe inside case.

Pack space full of magnesium oxide powder.

 

[tbuelna]

It would be helpful to know at which exterior surface the heat exchange occurs. To maximize heat transfer efficiency, the wall thickness in this area should be kept as thin and uniform as practical. For example, if the heat exchange occurs at the flat top surface shown in the sketch, then a good construction approach would be machining or casting the lower section and closing out the top with a very thin sheet metal plate furnace brazed or diffusion bonded in place.

Brazing is a well established and reliable method of constructing heat exchangers. Diffusion bonding would be more expensive, but a diffusion bonded component is generally considered to be equal to one produced from a single piece of wrought material in terms of reliability.

Hope that helps.
Terry

 

[Artisi]

sampsonr: It's not the material that's the problem, it's the design. Change the design to something that can be achieved using simple manufacturing techniques and your problem goes away.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[KENAT]

(MikeHalloran - I was replying to the post from Msquared immediately before mine.)

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[MikeHalloran]

We need to start using Mickey Numbers...

Mike Halloran
Pembroke Pines, FL, USA

 

[msquared48]

That's "Mikey" numbers. At least I hope we are not mice...

Mike McCann
MMC Engineering

 

[BillPSU]

Here is a cooler that is currently being used at my company. It fits in your general size constraints