Cylinder ID needed

[Platy Von Kippington]

Hello everyone, I just picked up 3 used steel tanks off a local diver here. He couldn't give me the size or any information on them other than the working pressure, and my measurements aren't lining up with any of the charts I've referenced.

Approx. dimensions are 8"x25.5" (could be slightly off on this, using a ruler since my tape was lost)

Neck stamping:
DOT E9791-3500 TP5250
IA 615662R
81

all 3 were born 1997-1998 ish. One has an older DIN valve on it, the other two are on an OMS manifold.

My best guess is a HP100 of some sort, but there's no branding or identifying marks on them. I'm not too concerned about the brand unless I decide to sell one or more of them, but knowing the size would be nice.

Thanks in advance

 

[bletso]

They appear to be HP 100's (Sherwood marketed them as Genesis cylinders.) They are manufactured by Pressed Steel. I have four of them. Filled they weigh about 1 1/4 lb more than an AL80.

Dale

 

[Platy Von Kippington]

Thank you, good to know they are HP 100's and a stop by the LDS for hydro confirmed it. I did some research on them, and it appears that PST tanks have a flat bottom, whereas these have a rounded bottom, making the Asahi tanks. Would this be correct? I know my daily trip to the gym was taken care of trying to lift the doubles into my car, they do feel somewhat heavier than an AL80.

How are these tanks in the water? I've been reading mixed reviews, mostly dealing with "head-down" trim issues. Any additional thoughts?

 

[bletso]

Those are definitely manufactured by PST. Their symbol is visible just past the serial number. PST's are all round bottom cylinders, at least that series is.

Dale

 

[Platy Von Kippington]

Sweet! Thanks for clearing that up! Can't wait to put these to use

 

[jar546]

They are 100's as confirmed by others and through your suspicion.