Aluminum tanks High Pressure 74 vs 80

[jsado]

DOT-3AL3442 FN00000004 M4002 11C07 CATALINA C74 SP12 TC-3ALM237
DOT-3AL3000 ASO454914 M4002 03C07 CATALINA S80 TC-3ALM207


Can someone tell me what the differences are between these 2 tanks?

 

[Charlie99]

Crown Markings of a SCUBA Cylinder describes the meaning of the various sections of the marking.

The tanks are like you described above ----

the second set of markings are those of a Catalina S80 tank -- what is commonly referred to as an "aluminum 80" or AL80. 3000psi fill pressure, 207 bar.

The 1st set are for the C64. 3442psi or 237bar fill pressure. C64 model number. Probably around 64 cubic feet of air when filled to the service pressure, but that is just a guess from the model number. The stampings don't actually have internal volume (aka water capacity) or fill volume at the service pressure.

Catalina has other "C" series tanks, including a C80. The C80 has a 3300psi fill pressure, and is close to neutral buoyancy when empty. The S80 is about 4.4 pound positive when empty.

The markings on the tank don't tell you what the empty buoyancy is unfortunately, since this is what you look at to figure out how much lead to add or subtract from your weightbelt when changing from one type of tank to another.

 

[Nemrod]

Catalina Cylinders

The link is the description of catalina cylinder markings. I do not see on their webpage a product that matches the numbers the OP has provided for the smaller cyclinder.

DOT-3AL3442 FN00000004 M4002 11C07 CATALINA C74 SP12 TC-3ALM237
DOT-3AL3000 ASO454914 M4002 03C07 CATALINA S80 TC-3ALM207

The S as per their page followed by 80 means it is a 80 cf tank intended for scuba. The C74 is different.

The only 3,442 service cylinders I find are steel and are not from Catalina. Perhaps I am having a brain cloud today.

N

 

[jsado]

DOT-3AL3442 FN00000004 M4002 11C07 CATALINA C74 SP12 TC-3ALM237
DOT-3AL3000 ASO454914 M4002 03C07 CATALINA S80 TC-3ALM207

There are a few things about this tank that have really caught my interest. Perhaps I'm wrong, but the serial# appears to indicate that it is the 4th tank from the run. It's from Catalina's C series, which I really don't know what that even means. I have no idea what the SP12 stands for..... and I'd like to know what the difference is between alm207 and alm237.....

 

[Charlie99]

Per the link in my post above, Crown Markings of a SCUBA Cylinder

SP12 The cylinder outlet thread designation as specified in CGA TB-16.

This tells us that the threads in the neck take the most common type of valve available (someone else can jump in with the exact diameter and thread pitch ..) Per the Catalina website, that SP12 marking should be on your S80 also.

The TC-3ALM237 and TC-3ALM207 are Transport of Canada (Canadian equivalent of DOT) marking. the tank is made out of aluminum and is approved by Transport of Canada. The 207 and 237 are service pressures in bar (about 14.5psi per bar). The DOT marking at 6the beginning of the stamping is the US DOT marking and pressuer in psi.

207 is the service pressure of the S80 in bar. 207 bar = 3000psi.
237 bar = 3442 psi.

It does indeed appear that you have serial number 00000004 !

 

[Nemrod]

It looks like Catalina needs to update it's web page, I guess?

N

 

[danemeyer20]

what are the dimensions of the HP 74 aluminum being that you have seen the tank? Is it the same size as an AL80?

 

[jsado]

what are the dimensions of the HP 74 aluminum being that you have seen the tank? Is it the same size as an AL80?

The hp74 is about 3 inches shorter than the al80.... and YES, Catalina definitely has to update their site.

 

[sierra23]

I think these tanks are older tanks - that is why they are not on Catalina's site. Many people question this request and say they have never heard of them. When I dive with my ONE tank, I use 2-4 lbs less weight and my tank has little or no change @ the end of the dive. It is so much more comfortable for me, a short female, to use. I would like to purchase another one but all of my LDS stay clear because it is a "custom" order and spendy. I have agreed to the extra charges. If anyone out there has a new Catalina 74 alum. HP tank please let me know. I would like to purchase one. Thanks.

 

[Kiwi303]

03C07 and 11C07 look like Hydro proof dates to me, is the C a little stylised and not really a standard alphabetical C like all the other stamping on the crown?

It could be Catalinas' maker/proof hydro mark, like Norris had an N in a diamond and Arrowhead Industrial Services has an A with a line down the middle making it look like an arrow head.