What is this gift I received?

[Eric Sedletzky]

Ok, so this is an LP, fill to 2250? None of the Hydro stamps, even ‘78, had a +, so no 10%?

Theoretically, but you can try begging for a 2475 fill.

 

[bradlw]

it's why the roundout process is important for these older galvanized tanks.

what do you mean by "roundout"?

I asked my Phd metallurgist brother in law about this idea of loss of elasticity when stored long-term without pressure cycles. In my initial contact, he basically offers no ideas about what it could be. Focusing more on corrosion, pits, and cracking.

I'm no metalurgist....having only taken the one metallurgy class in engineering school many decades ago + a few other materials and stress related courses. The only possibility that I can dream up regarding tanks in storage has to do with some sort of internal, possibly integranular, corrosion that would escape detection during the VIP...except that it seems to me that something like that would lead to brittleness and cracking...not loss of elasticity.

Besides, stress cycles lead to fatigue...and if to the point of deformation work hardening .... which would be the opposite of the theory.

Right now anyway, I'm falling in the camp of "coincidence"

 

[ScubaBunga]

what do you mean by "roundout"?

I asked my Phd metallurgist brother in law about this idea of loss of elasticity when stored long-term without pressure cycles. In my initial contact, he basically offers no ideas about what it could be. Focusing more on corrosion, pits, and cracking.

I'm no metalurgist....having only taken the one metallurgy class in engineering school many decades ago + a few other materials and stress related courses. The only possibility that I can dream up regarding tanks in storage has to do with some sort of internal, possibly integranular, corrosion that would escape detection during the VIP...except that it seems to me that something like that would lead to brittleness and cracking...not loss of elasticity.

Besides, stress cycles lead to fatigue...and if to the point of deformation work hardening .... which would be the opposite of the theory.

Right now anyway, I'm falling in the camp of "coincidence"

See https://www.ctcseminars.com/files/technical/PST Tecnical bulletin D100.pdf

 

[RIHappyDiver]

Another question, should I replace the J valve on this? Can I replace it, or are the threads odd? Not sure of its age, and there are no markings on it. There is a little surface rust at the orifice, but it looks to be in good shape externally. Don’t know if it was serviced when the tank was hydroed last year.

Thanks,
Erik

 

[Still Kicking]

Another question, should I replace the J valve on this? Can I replace it, or are the threads odd? Not sure of its age, and there are no markings on it. There is a little surface rust at the orifice, but it looks to be in good shape externally. Don’t know if it was serviced when the tank was hydroed last year.

Thanks,
Erik

I would use it. Valves are very reliable. Zip tie the lever down (open).