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Heard a pressure vessel hit 15,000 cycles during a test and it really made me think about fatigue...
That number means it's been through a full heat-up and cool-down 15,000 times, which is way past the standard design life for that old unit in the Pasadena plant, so if you're working on similar vintage gear, maybe double-check the last inspection logs.
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wesley_jones6mo ago
Wasn't the design life like 5,000 cycles?
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wesley_jones6mo ago
Yeah, I had to look it up because my memory is about as reliable as that old vessel. The spec sheet I found said 5,000 cycles for the design life, but I wouldn't bet my lunch on it.
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kelly.hannah6mo ago
Why do spec sheets always feel like best case guesses?
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henryp403mo ago
The spec on my old pressure washer said 3000 PSI, but I think that was measured in a vacuum chamber on a perfect day. I bought it new and after about 50 uses the pump started sounding like a bag of rocks. Now I just assume any cycle count is what you'd get if you never turned the thing on and stored it in a museum. My memory is so bad I can't even remember if I've already changed the oil in my truck, let alone trust a 5,000 cycle promise. I figure if a spec sheet says "best case" I should plan for the worst case and add a zero to my budget.
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