PET Plastic for tanks?

[UncleChuck]

In home brewing you can get carboys (large jugs for fermentation) made of PET. If you are going to use plastic instead of glass, everyone suggests PET. It's incredibly tough, doesn't crack like polycarbonate does, and is less reactive than other types of plastic.

Has anyone thought of using this material for tanks? After reading about people cracking their polycarbonate tanks with certain juices, PET came to mind as a good replacement.

Check out this link here:

SKS Bottle & Packaging, Plastic Tubes, Plastic Tubes, Clear PET Round Tubes w/ Silver Metal Screw Caps

As you can see, PET is just as clear as polycarbonate, it's stronger, and I'm thinking won't have the same chemical interaction issues as polycarbonate. Those are just little spice bottles or whatever, but I'm sure you can find it in it's raw tube form if you look a bit longer.

The only issue I could think of is that it's generally more flexible than polycarbonate. Whether or not this would be an issue with the thicknesses used for tanks (Or more specifically the thickness of raw tubes you could find) I do not know. It doesn't actually stretch, just flexes, so it shouldn't be an issue with sealing against the end caps.

I just thought I'd throw this out there, currently none of my favorites juices are giving me any problems with my polycarbonate tanks so I don't really have any motivation to try it, but I thought someone else might like the idea.

 

[Fiamma]

How will it handle the hot end of a carto?

 

[UncleChuck]

That's a very good question. When brewing you pour your wort ( un-fermented beer) into your carboy shortly after the boil. Generally you cool it down a bit to avoid killing the yeast with too high a temperature, but it's still very hot. Hotter than the juice or end caps would get while vaping (juice and end caps being the only part that actually touches the tank material, at least on every design I've seen) so it should be fine.

Now that I think about it, when using metal end caps it could potentially be a problem. Honestly I don't know the upper end of PET's temperature range before problems arise, but on my tanks (with plastic end caps) the caps never get very hot, even when chain vaping. I've never had a tank with metal caps, so I'm not sure how hot they get.

I'll try to do some research online about the temperature thing.

EDIT:

Wiki says 540F is when PET starts to degrade, so unless you are doing some unholy things with your tanks the heat should be no problem.