Where to get a prototype vacuum flask manufactured?

Hi TR,

What is the construction material for the flask? That would set what kind of shop you would go to for the prototype. You will need to have drawings of exactly what you want to make and, for something like this, a 3-D drawing would be best.

Depending on the material and the intricacy of the design, yes, it could get expensive.

Sorry I don't have more specific advice.

Mike

I assume that two tubes, one welded inside the other won't work for you. If you need curved tubes, with constant diameters, just put two straight tubes together, fill them with water, freeze it and bend the tubing while the water is frozen. Weld ends, etc.

If you need spacial shapes hydroforming two halves of appropriate dimensions will work.

As usual, not enough information to go with.

Try checking out "Dewars"; basically industrial-size Thermos^® bottles. With luck, there may be some off-the-shelf versions that would work, unless you have special geometric needs.

Thanks for all the advise, much appreciated!

Metal or glass would be the material. Basically what I am looking for is a Thermos^® , shaped very similar to a hip flask but that can store approximately 20 Litres.

Dewars might in fact be the solution so thanks for advising. They definitely come in the capacity I'm looking for, although I am unsure about the shape. From a cost point of view maybe I might have to purchase a regular Dewar and re-think my design. I would rather get one prototyped but as with any new design compromise may be required.

I'll be sure to post again on any updates.

Cheers!

If you can come up with a 20-litre hip flask, kramarat, lyn, and I might be the start of a market base; and LynDoor™ Industries would surely plug it, albeit ineffectively. Ya gotta fill it with the right stuff, though, whether Gran Patron, green Chartreuse, or Pure Ole Panther Piss.

20 litre??????????? That's a backpack.!

Look at the manufacturers of liquid nitrogen containers. they are in sizes as you would need. Material is usually a stainless steel due to its lower conductibility. Some have a glass Dewar inside but not all of them.

Look here.

Specifications

Insulated bucket,thermos bottle
Material:Stainless steel 304/316L
Capacity:20L,25L,30L,35L,40L,45L,50L.

keep warm

Just a thought this might work.

I had a second look at your problem. The overall dimensions are quite small (d x h ≈300x300mm) and the temperature difference as well limited (max 80 °C). It could be possible to use a thermal insulation other than vacuum and avoid an expensive solution. All depends on your time constant for the cooling T= Σ(M.cp)/(k*A) where M is the mass of water and the container wall in contact with it ; Cp is the thermal capacity for the same; k= global total heat transfer coefficient of the wall and A is the transfer area. If the constant is not very big then other solutions are possible at a lower total cost. It is possible to use only an external insulation for a stainless container different foams have such a low heat conductivity that it can be a real solution to use them.