Looking for a Vacuum Flask Manufacturer

This site is an engineering forum,, not a purchasing service.

Go here:GlobalSpec.com and search for a manufacturer.

Sounds like you should hire someone who knows how to purchase things.

Sorry about that. Thank you for the info, lyn.

Panos

How to produce a shape like that seems to me a perfectly valid engineering question.
Dunno what's up with Lyn, probably swallowed a scorpion with his cereal this morning... although it is rumoured he doesn't eat cereal..
Instead he has broken glass, with milk on... and NO sugar.
Unfortunately metal forming techniques are outside my sphere of expertise. However I would imagine forming a douple walled hour glass shape would involve forming the two parts and joining (welding, presumably) the parts together. Maybe a plain cylinder could be made and then expanded into a mold with hydraulic pressure... dunno.
Del
(Don't tell Lyn I said that, he'll be PM'ing me scorpions next....)

Hi Del,

Thanks for the back up. :)

The problem that the manufacturers in China said they had was welding a shape other than a cylinder.

I thought about getting a standard double-wall vacuum cylinder and nest it inside our shape which would function only as a shell, but the weight would be too much for a portable 400ml flask and probably the price too.

On top of that, Lyn's link was not very helpful. Couldn't find a vacuum flask manufacturer. :(

Panos

Ok,

Let me try to redeem myself.

First, looking at this from an engineering perspective, it is not a difficult task.

One way to do it is to form two different shapes, one slightly larger than the other.

That's a total of 4 pieces, two of which would be mirror images of each other. The other two, slightly larger mirror images.

Laser welding these would be very simple and is done every day. CNC lasers are common place. Stainless steel is VERY easy to weld using lasers and lasers LOVE to weld it.

Del's idea of hydroforming would work, as would a simple set of matched metal stamping dies. The same die would work for both halves of the inner shape, and another one would form the outer shape.

The threads could easily be formed into the neck of the outer pieces and a joining flange could be formed into neck of the inner shape.

I see this as an easy task for any competent prototype fabrication shop. Turning it over to a volume producer should not be a difficult task as well.

Forgive my abruptness, the title of the thread put me off.

No scorpions for you Del.

Hey Lyn,

Thanks for the informative reply. My designer also thought that this is something that can be done easily. Maybe the sub-contractor I've contacted to find a manufacturer deals with factories that are still in the old age.

I'll take this information and use it for future contacts and hopefully I'll find a decent manufacturer with a today's-age equipment.

I get what you're saying about the title. In an engineers forum it definitely looks off-topic.

Thanks again, everyone. If you have any other thoughts, I'll be grateful to hear them.

Panos

Lyn,

The only negative about the solution you're mentioning is that I have to make two molds, which raises the costs significantly.

Is it possible to make only a mold for my design and nest inside it a regular cylinder and weld these two? I have a feeling that it's also something doable, right?

Panos

Of course it would work. Why didn't I think of that?

Thanks, Lyn. :)

Panos

We had a related question come op 2-3 years ago. The bottom line is that I found no-one in the USA who would even bid against manufacturers in China. I'm fairly certain that if your quantities are large enough, you will find Chinese manufacturers who are anxious to work with you.

Hi welderman,

Well, my first order will not be so large, since it's a one-man startup (1,000 units,) but without even talking about MOQ they said they are not willing to take a crack at it. They didn't say 'we want this annual order to do this.'

Panos