Is it safe to pressure ferment in a Spiedel plastic fermenter?

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Jan 29, 2016
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This is what 15psi does to a Spiedel plastic fermenter. It was at 15 psi for less than 5 minutes as I figured out the adjustment on the spunding valve required to hit 10 psi, which it's been at for a couple days now. A friend shared this pic with a buddy who works for a micro brewery and he said it looked "dangerous as hell". This concerned me enough to drop it down to 5psi, which Norcal implies is the maximum at which they tested the "pressure relief valve" version of the top piece I bought from them (mine is the "Speidel Ball Lock Gas Attachment with Thermowell").

I'm trying to think of where the weak points are, how they would fail, and if that failure would be of the catastrophic variety. The worst I can think of is the top exploding and making the brass spunding valve an airborne projectile, but I'm not sure how realistic that is. I'm guessing if it failed it would be at the seals or maybe a seam in the plastic, but wouldn't that just shoot out a jet of CO2 or beer? It couldn't just explode spontaneously like a bomb sending HDPE shrapnel everywhere, could it?

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