[mr_feelgood]

OSHA, eat your heart out

[William May]

Pressure vessels are normally tested hydrostatically, which means they are filled with water, and then WATER is pumped in to give the pressure required to test the tank. If there is a failure or a leak, the pressure disappears instantly when the leak occurs, and there is never an explosion. Pressure drops from 1000 psi to 0 in 1/10th of a second, and there is no stored energy to generate an explosion or kill anyone. Any liquid can be used for this, as liquids are ALL incompressible.

We also used to use that procedure to force landing gear strut tubes out of the landing gear casting, which took as much as 20 tons, but usually only 10 tons for good struts. You bled the cavity, then applied hydraulic pressure, until the tube popped out of the casting. It would just go "plink!" and the parts would separate, and the fluid would run into the drain pan they were sitting on. If you failed to bleed them properly, and there was any air left in them, they would punch right through a metal-framed wall and go into the next room.
They had STRICT procedures for this operation, and multiple checks to insure there was NO AIR in the strut assembly.

If it took 20 tons to separate the strut tube from the landing gear axle forging, it was considered scrap, and you just threw it away, so the separation forces were noted after disassembly and put on the paperwork for the strut repairs.

This is the same procedure used to hydrostatically test high pressure air bottles, locomotive boilers, welding gas bottles, propane tanks, etc.

High pressure testing of carbon-fiber oxygen and nitrogen bottles for aircraft are also done this way, but they also look at how much displacement occurs at maximum pressure. The bottles are filled with water, placed in a water tank, and the water level is set precisely. Then the bottle is pressurized to the test pressure, usually 8000, to 10,000 psi, and the bottle growth or expansion is noted. If the bottle expands over 1% to 3% (depending on the bottle and the pressure rating) the bottle is normally condemned and is scrap. This is the 5-year ICC Hydrostatic test on pressure bottles.

If they had paid to do this testing on the Ocean Gate submarine, they would have seen the problems with it, without ever having it fail, or kill anyone. Ocean Gate just did not want to spend the money for that testing.

[MikeyP]

Russian OSHA pounded 15 more liters of potato nectar and chalked it up to a normal day.

[akham]

Originally Posted by William May ↗

Pressure vessels are normally tested hydrostatically, which means they are filled with water, and then WATER is pumped in to give the pressure required to test the tank...

OMG! You really did go to the Colombian School of Plumbing and Forensic Science!

Sounds like you have lots of interesting experience and that you have graduated from a drip to an ex-spurt.

(Seriously though, I thought your post was really interesting!)

[Roosta]

Welding a pressurized tank is a smart thing to do.

They should have marked the leak area before venting it overnight & the doing the patch ups.

[AmericanDaywalker]

Originally Posted by spycosis ↗

I don't know wtf the plan is but looks like they are grinding rough edges off, not welding. Not that it makes much difference. I don't think anyone should be near it though if it is being pressurized.

For sure they were grinding, that isnt weld sparks. Thats like 5-7 inch hard wheel stones. Thats not welding.

[William May]

Originally Posted by akham ↗

OMG! You really did go to the Colombian School of Plumbing and Forensic Science!

Sounds like you have lots of interesting experience and that you have graduated from a drip to an ex-spurt.

(Seriously though, I thought your post was really interesting!)

No, ANYONE can claim graduation from the "Colombian School of Forensic Science and Plumbing." I am NOT an elitist!

All you have to do is state that you attended, and you automatically become an alumni! Anyone who has been looking at this site for years would EASILY qualify, just from the amount of stuff people have seen on here. And if you know how to do actual plumbing, you graduated Magna Cum Laude!

CELEBRATE, CSFSPers!

[William May]

Also, when contributing, just state the very first thing:

"As a graduate of the Colombian School of Forensic Science and Plumbing, I.............................and then state what you think happened, or could have happened, or might have been caused by Squirrel Elements, or other factors, or whatever!

[William May]

Originally Posted by akham ↗

OMG! You really did go to the Colombian School of Plumbing and Forensic Science!

Sounds like you have lots of interesting experience and that you have graduated from a drip to an ex-spurt.

(Seriously though, I thought your post was really interesting!)

If you want to see hydrostatic testing actually done, go to Youtube, and look for "Hydrostatic testing a model locomotive boiler" and you can get a class in a nutshell.

[akham]

Originally Posted by William May ↗

If you want to see hydrostatic testing actually done, go to Youtube...

I've watched bit about COPV failures after the SpaceX incident. Its fun watching people bust Elon's balls.