I borrowed some landscaping tools from my brother in law and he offered his old air compressor since he doesn’t use it. Broken tube. Easy normal part to replace.

Got a air compressor accessories kit on the way home. Replaced the hose and tip. Plugged it in outside. Left it for 10 minutes…

Never turned off. Hmm. Might be one of those that have a release valve and not auto shutoff.

20 PSI? That’s odd. Unplugged it. Hissing…
Air coming out the bottom. Maybe a puncture?

Found the spot. Got 80 grit sandpaper and 3300 PSI rated epoxy. Sanded and found rust.

Patched it and my spidey sense went off while looking at the epoxy…

Did a search:

A leaking air compressor tank—especially with a leak on the bottom where corrosion is likely—can be extremely dangerous, even if “repaired” with epoxy or other sealants. The primary risk is catastrophic rupture under pressure. If the integrity of the tank is compromised (for example, by internal rust or a patched-up hole), the tank can explode with explosive force, launching shrapnel and causing severe injury or death, as well as property damage

When tanks rupture, the velocity of air and shrapnel can be lethal. For example, a 60-gallon tank at 150 PSI can explode violently, creating 680 mph air blasts and extremely loud noise, both of which are highly hazardous for bystanders

Nope! Tossing it!
Dodged a nearly literal bullet there.

Bonus shots:

  • 𞋴𝛂𝛋𝛆@lemmy.world
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    2 months ago

    Yeah. At the union hall where I got my structural steel welding cert, there was a whole yard of “don’t do this shit” that they walked the class around. Almost all of the examples had killed someone too. There was a whole section on definitely do not compress liquids in random dumb ways. I don’t remember the details but there was a box like a custom made toolbox for a pickup truck that someone had built square tanks into and was doing something like a service truck transferring fluids to heavy equipment. It wound up blowing apart catastrophically and killed more than one person. They did the investigations at that hall so they had all the bad stuff already and had to keep it for a designated amount of time for legal reasons.

    Air is not super duper dangerous like any kind of fluid. Fluid is what will get you, and that compressor will have fluid in the bottom, so it can get you.

    That was my main take away from structural steel; compressed fluids = xrays + engineer & with no exceptions.

    • varyingExpertise@feddit.org
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      2 months ago

      Air is dangerous as well. A hydraulic system quickly loses energy on failure because oil is nearly incompressible.

      Compressed gases or liquids that are beyond their boiling point at atmospheric pressure store a lot more energy at pressure and release it a lot more violently than hydraulics when experiencing a surprise decompression.

      Let’s take a 100 liter compressor tank that’s buffering at 10 bar:

      For an isothermal expansion from high pressure to atmospheric pressure, the energy is:

      E = P₁V₁ ln(P₁/P₀)

      Where:

      P₁ = 10 bar = 1.0 MPa

      V₁ = 100 liters = 0.1 m³

      P₀ = 1 bar = 0.1 MPa (atmospheric pressure)

      E = (1.0 × 10⁶ Pa)(0.1 m³) ln(10)

      E = 100,000 J × 2.303 E = 230,300 J (or about 230 kJ)

      TNT releases approximately 4.6 MJ/kg of energy. 230,300 J ÷ 4,600,000 J/kg = 0.05 kg or 50 grams of TNT

      Of course a tank rupturing will expand a lot slower than TNT, but the energy is the same and when half of the tank shell points towards some offices next to the workshop, the first three walls will be impressed pretty much the same way by the suddenly very agitated piece of steel.

      Had an air tank fall over in a stupid way during refilling at our local fire station last year. Valve broke off at nearly 270 bar and the thing went off. Now there are new rules, new indents in the concrete walls and at least one fireman that reacts a bit jumpy to “clang” like sounds.

          • dustycups@aussie.zone
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            2 months ago

            The condensate is still way over 100 degrees due to pressure. If it reaches the top of the pipe it can create a shock wave (think water hammer) that will travel to the next corner and blowout. The condensate then turns back to steam at atmospheric pressure.

    • Taldan@lemmy.world
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      2 months ago

      The fluid is not what will kill you. The shrapnel will. The metal vessel is far more dangerous than than any fluid that will be in it