Pressurized Box Engineering Help
Pressurized Box Engineering Help
(OP)
thread794-92440: Pressurized box: Pressurized box
Hi, I'm looking to create a pressurized box that is very similar to the one listed in the forum above. It will be about 25 inches x 14 inches x 16 inches and will need to hold about 18 psi. I want to a lightweight material and the box have thin walls to have the most possible space inside the box. What type of material does anyone think I should use?
I was thinking a plastic, with a plastic lid... Is that possible to create and hold that much pressure?
Hi, I'm looking to create a pressurized box that is very similar to the one listed in the forum above. It will be about 25 inches x 14 inches x 16 inches and will need to hold about 18 psi. I want to a lightweight material and the box have thin walls to have the most possible space inside the box. What type of material does anyone think I should use?
I was thinking a plastic, with a plastic lid... Is that possible to create and hold that much pressure?





RE: Pressurized Box Engineering Help
Patricia Lougheed
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RE: Pressurized Box Engineering Help
Why a box shape? What kind of cover?
Operations: How often are you loading this "load" How heavy is it? Are you going to manually insert it? Move it in automatically? Is it on rails of some kind? By crane or What is your "load" and what is its shape? on a sling?
Sure, anything can be built, but you have not provided enough information to discuss your problem.
RE: Pressurized Box Engineering Help
Steel is the most economic choice due to its strength. Other materials, such as light weight fiber glass or fiber composite material (used in aircraft) may do the work, but I believe the cost will be high.
FEA is the best tool since you may need to modify the design many times.
You can put stiffener bars around the outside to brace it, especially the corner areas which are the weakest, that way you can reduce the wall thickness. Everything can work out well by FEA and easily adjust and optmise the shape. but to prevent leak from the lid is the major issue you need to concentrate. Clamp all around or by bolting ?
Build a model after verified by FEA, and water test it, then you are good to go.
RE: Pressurized Box Engineering Help
As stated above, a cylinder or sphere is much better
How about an inexpensive short section of Sched 40 PVC or GRP pipe with end caps ?
The 18 psig should be no problem....... the small volume means it will fly under the code regulations
RE: Pressurized Box Engineering Help
So my main problems are which material would be strong enough to withhold 15 psi in a box shape? And what is the best type of lid and gasket combination that could seal the box completely, but being very quickly and easily opened and closed.
RE: Pressurized Box Engineering Help
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RE: Pressurized Box Engineering Help
The problem will be sealing that 14 psig for the duration needed for your process - and THAT job of sealing a gas cannot readily be done (particularly with any form of "box" pressure vessel pressure vessel) - simply and easily with "one or two" hand-twisted screws.
Round pipe with a rotating cover plate and lugs? Maybe - if the cover plate were stiff enough to hold firmly all the way around the sealing surface so only two lugs would clamp evenly around the periphery of the lid.
What is the pressurized gas? Hoqw much does it cost poer cycle? How flammable, toxic, corrosive? How will you vent it, refill it, where will the released fumes go when you vent it?
RE: Pressurized Box Engineering Help
It's very simple. It's just air going into the unit. It will have an automatic pressure valve with a compressor to always maintain the pressure. It's not for me, otherwise I wouldn't mind it have a few more bolts to really secure the top, but it is for people that won't use it unless it is very easy to use. So the easier it is to open it and securely close it the better it will be. The pressure and everything else will be taken care of by just plugging it in.
The weight of the whole unit should be light enough to pick up and move to wherever you would want. So I was thinking of the whole thing being aluminum, with the lid having a gasket (thanks to jtseng123)? Anyone see any problems with this or recommend something else?
RE: Pressurized Box Engineering Help