Super Soaker Central

I'm new to this site and I was just wondering if any one knows how many PSI a 750 mL or 25oz coke bottle cant take?

Welcome to SSC.

Those bottles are usually made from PET plastic. Here's a page about reported burst pressures for those bottles. Take a look at this video testing burst pressure too.

Be aware that it's a good idea to operate well below the burst pressure. The burst pressures for PVC pipe are several times higher than the rating because a sudden impact or other conditions can affect the integrity of the pipe. I would not suggest exceeding 100 PSI with a bottle.

Thanks that helps alot.

Also, I would say it's probably safer, though also much harder to engineer, if the bottle connection is weaker than the bottle. Having the whole bottle rocketing off is safer than having plastic shrapnel flying.
Like I said, though, it'd be harder to engineer. In any case, if you're worried, there are other things you can do. A pressure relief valve is an obvious one. Also a protective outer case around the bottle, both to help stop shrapnel if it does burst, but more importantly to protect the bottle from scratches that would weaken it.

yah i was thinking of building a shroud of some sort for safety.

Welcome aboard!

A strong bottle connection plus a pressure release valve would be the most precise and reliable way to control the pressure. If you're looking to make the bottle safer, I'd use metal screen mesh wrapped around it with epoxy to secure it in place. I know it's been done to pressure rated PVC to increase the pressure at which spud guns operate (although that's not a smart idea since you might as well use metal pipe and fittings).

Is there a real need to use a bottle instead of plastic piping? If PVC pipe is available, there is no reason you shouldn't use it. It's stronger for one thing, and still cheap for another. It's perfect, provided it's available.

Drenchenator wrote:Is there a real need to use a bottle instead of plastic piping? If PVC pipe is available, there is no reason you shouldn't use it. It's stronger for one thing, and still cheap for another. It's perfect, provided it's available.

I used plastic bottles since I'm not able to find any large diameter pipe. Yes, PVC pipe is cheap, but using plastic bottles (if you do it correctly) is a lot cheaper (although sometimes, it's not always the best solution). They're also available to a large amount of people, where PVC sometimes isn't.

i have access to plenty of PVC. i was mostly looking for a way to save some money, which i realy shouldnt be that worryed about as my dad is a contractor so i could be able to pick up most of the small parts from scraps, but he doesnt use large diameter pressure rated so i was looking for a way to get around the need to buy large diameter PVC and fittings.

Yeah, large diameter pressure rated PVC is not always easy to get hold of. And I for one would never consider using waste or drain pipe for PC's. Fizzy drinks bottles are designed to hold pressure.
Also, having it clear's a perk. That way there's no need for a gauge, just watch the water in the PC.

If you can create a solid connection and protect the bottle from any impacts, then it's a wise choice (although the same can be said for PVC). Drain pipe is somewhat usable - water builds 1 atm or 15 PSI of pressure for every 30 feet of elevation. I'm not sure what heights of drain pipe are used in construction (kevin, might your dad know?), but even a hundred foot tall pipe would have over 45 PSI at the bottom.

I'd rather have a balloon pop than PVC shatter, though.

I think drain pipes are very rarely full of static water though. Normally they'll be either empty or have some flowing down. They're only going to fill if they get blocked.
Also, 100 feet is about 10 storeys. I too know little about construction, but that's beyond the realm of houses. Probably tall buildings use stronger drains.