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Regulations for pressurized PET bottles

Regulations for pressurized PET bottles

Regulations for pressurized PET bottles

(OP)
I am not sure whether this is the right forum for this question but it is my best guess...

We are considering using PET drinking bottles as short term pressure storage devices (user inflates and then deflates the device withing few minutes) in a product that we want to sell. We have a pressure relief valve making sure the allowed pressure can not be exceeded.

Due to to bottle size (1.5 l/50 fl. ounces) and the pressure (6 bar/90 psi) in Europe (where we are from) the device does not have to be tested/licensed but we need to proof "good engineering".

What is the situation in the US? What do we need to fulfill so we can sell the product in the US market?

Thank you very much for your help!

RE: Regulations for pressurized PET bottles

Good question. I have no idea what, if any, regulations would apply. The device is below the volumetric limit set in ASME VIII, so it's not a pressure vessel. It's not pressure piping either. Some might argue that in Canada it would be considered a Category H fitting, but even that view is a bit suspect. So, aside from product liability, I don't know what if any regs would apply in North America.

RE: Regulations for pressurized PET bottles

Fredddie:
I’ll bet that the typical PET beverage bottle, at whatever max. pressure their industry std. is, is not fatigue tested for many reuses, as you suggest for your product might be. I would also be concerned about environmental degradation, embrittlement from UV light and the like. Over time, does dry (dry on both sides) PET deteriorate/degrade differently than if it is wetted on one side? Do you do anything within your product enclosure for these bottles to contain the flying debris if one of these bottles does fail? Can the bottles be pressurized to their max. pressure and then not deflated for long term storage, to what affect, matr’l. creep, etc? Is the formed geometry of some bottle shapes more favorable for your long term use? As Moltenmetal suggests product liability and user/public safety (consumer product safety) will be all important, and are probably the guiding design considerations for the current bottles being manufactured.

RE: Regulations for pressurized PET bottles

If you look at children toys, there is a rocketry kit consisting of a clear plastic with a mounted projectile which can be become airborne when the air pressure reaches a certain point. The air pressure is delivered by a hand operated pump. The bottle fitting for the projectile also incorporates a relief valve.

RE: Regulations for pressurized PET bottles

Yes, I shoot such a bottle off to 75-100 feet at 25 psig. Bicycle pump pressure. The 7 year old twins love it.

RE: Regulations for pressurized PET bottles

6bar sounds like a lot of pressure for a"standard" plastic bottle. Repeated cycling will lead to fatigue and failure. To get away with that I think you're going to need a FOS on failure of over 2 and repeated cycles in excess of what you can expect a user to do.

If this is for public use then you need to be much more careful than something designed for a lab or industrial use. Assume it will fail and make sure it's failure can't fragment and eject slivers of plastic like a fragmentation grenade. ...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Regulations for pressurized PET bottles

(OP)
Thank you for your inputs.

We will most likely be using a returnable bottle which are more robust than the one way bottles we know from the stores today.

Does anyone know who in the US would be the right contact to help us professionally with the test requirements we need?

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