FIRST air cannon robots PVC??

[artdutra04]

The smaller the diameter of PVC, the more pressure it can stand. In this table, you can see the maximum operating pressure and the minimum burst pressures for various grade and diameters of PVC and CPVC pipe. A 2" Sch 40 PVC pipe has a maximum operating pressure of 166 PSI. If need arieses, instead of using a larger diameter pipe to store more air, I'd just use multiple 2" diameter accumulators clustered together. Also, try to use Schedule 80 whenever possible; the extra wall thickness will certainly help lessen the danger of the accumulator rupturing.

Also to note: PVC loses a lot of strength as the temperature rises. If you ever plan on using your air cannon in 100^oF weather, PVC's maximum operating pressure drops to only 60% of it's original strength. (A 2" PVC accumulator would only have a maximum operating pressure of 99.6 PSI. In hot climates, this may become a major issue.)