identifying a tank

[bradlw]

I posted this attached to a very old thread I found a few days ago. No responses so I'm thinking maybe it's not getting visibility since it was an old and dead thread.
(if that's not the case, my apologies for the duplication)

Here's my question:

old thread, it answers part of my question
I have a set of doubles that I put together from used tanks twenty some odd years ago. I can't remember what they were. Still holding trimix....tag specifying the blend is long gone.

I understand from this old thread they are made by PST
how can I confirm the capacity and bouyancy characteristics?
I think they MIGHT be PST-100
roughly 2 inches shorter than my Al80

PST 100
3500psi, 102ft3, 7.25 in diameter, 23.94 inch tall, 34.1# empty, -1.3# bouyancy empty, -8.8# bouyancy full

in the plastic boots, they stand approx 24-3/4 inches to the top of the neck
marking is
DOT-E9791-3500 TP5250
239710 GALVANIZED USA

Do I have it correct?

there was a photo in the old thread if you care to look at it. It didn't come through in the "quote"

 

[runsongas]

sounds correct for the 7/8 UNF neck PST 3500 psi HP100s

 

[SlugLife]

Sharing pictures might help, specifically including any markings on the tank.

edit: Reading comprehension fail, seems you included the markings. But pictures still might help as some people might visually recognize them. Also a photo in the other thread.

edit 2: Those markings do not match my PST 100s. Though not all PST 100s may have the same markings.

 

[SlugLife]

Here are photos of the top of one of my PST 100s (note, I am NOT the OP for any readers)

• There are markings on both sides of the top of the tank. This is a single tank.
• The marking says "PST" on it.
• The size indicated by E7-100
• My tank appears to be newer than yours, so it's possible they changed the markings over the years.

 

[bradlw]

I had a picture in the original post you can see through the link...... I didn't have a copy of it handy when I started this thread earlier today.......
but I'll try to post it again here

 

[runsongas]

@SlugLife your tank is slightly different as it is the updated 3442 psi version E7-100 that came with regular 3/4 NPSM neck to use convertible din/yoke valves with. OP has the older 3500 psi 7/8 UNF neck that requires a 300 bar din valve.

 

[Tracy]

Yes, you have an HP100

 

[bradlw]

thanks!

 

[rjack321]

thanks!

hp100 with 7/8" valve threads and (only) a 300 bar outlet. Its intermittently either $$$ or challenging to source valves for these due to their age and the fact that this valve threading hasn't been used in 30 years. Be careful you don't ding the 300 bar outlet out of round as it'll be a big pain to replace it. They don't/can't take a convertible insert to yoke. Hydros require a pretest procedure or it's likely to fail so be sure to use someplace that understands galvanized scuba tank protocols for hydro - aka a shop that actually routinely hydro steel scubas.

 

[tursiops]

hp100 with 7/8" valve threads and (only) a 300 bar outlet. Its intermittently either $$$ or challenging to source valves for these due to their age and the fact that this valve threading hasn't been used in 30 years. Be careful you don't ding the 300 bar outlet out of round as it'll be a big pain to replace it. They don't/can't take a convertible insert to yoke. Hydros require a pretest procedure or it's likely to fail so be sure to use someplace that understands galvanized scuba tank protocols for hydro - aka a shop that actually routinely hydro steel scubas.

XS Valve, 300 Bar DIN outlet, 7/8 UNF inlet threads

The XS 300 BAR DIN valve with 7/8 UNF neck thread is for Air Service Only. This unique valve is designed for use with smaller neck diameter High Pressure cylinders. The valve is rated for 4350 PSI service pressure.

www.divegearexpress.com