Largest gas capacity aluminium cylinders?

[happy-diver]

Are they fake Fabers or ?

The two on the right are Faber Fabers with the two on the left Unique Fabers, much like your question dude!

But not unusual

 

[Tanks A Lot]

It seems that anything above a 200 bar fill pressure are carbon fibre cylinders, however the 20L x 200 bar model here might be able to be made to work -
View attachment 913617
Given that these are European cylinders designed for SCBA use I would think that DIN valves that SCBA and Scuba use would be readily available - does anyone know if DIN valves are available for that 25E thread code?

Would there be much difference in aluminium cylinders made for SCBA use and those made for Scuba use?

I have obviously misread your first post, as I assumed that this is for a non SCUBA project. Be careful with composite cylinders, very few are truly rated for underwater use. If the wrong composite is taken underwater, you risk very quick galvanic action under certain circumstances.
If you are dead set on 3200 litres and aluminium, look for these from Luxfer: P2594D-S12LX; P2942M-S15GB; T170A. I believe these are not composites or are permissible underwater.

Cylinders that come close are:
Luxfers 106W (Composite for underwater) 11.1L 300bar
Thunderbird aluminium 13.3L 228bar
Catalina C100 13.3L 228bar

You are unlikely to find a SCUBA valve that will fit a 25E or 17E connection, or any of the non standard thread sizes of M25x2, 3/4 NPSM and so on. There is good reason for the different thread norms, it is to prevent the wrong cylinder to be taken into an environment it won't appreciate.
There are tons of aluminium cylinders out there with a vastly bigger volume, but most won't be suitable for diving for one reason or another.

OXYGEN CYLINDER VALVE 25E X BS-3 (5/8" BSP RH(INT) AS PER BS 341 No.3) WP: 200BAR SCG D-VO2-E

Buy Oxygen Cylinder Valve 25E x BS-3 (5/8" BSP RH INT) – 200BAR, BS 341 No.3 compliant. Safe and durable valve for medical and industrial oxygen systems...

gasneeds.com

That will unfortunately not work. While the thread is also a G5/8", just as in the "DIN" connector, the BS341-3 #3 connector has a decidedly different geometry. The thread matches, but the BS341 expects a bullnose to be present on the regulator. These are for oxygen use, not SCUBA.

 

[RedSeaDiver2]

I have obviously misread your first post, as I assumed that this is for a non SCUBA project. Be careful with composite cylinders, very few are truly rated for underwater use. If the wrong composite is taken underwater, you risk very quick galvanic action under certain circumstances.
If you are dead set on 3200 litres and aluminium, look for these from Luxfer: P2594D-S12LX; P2942M-S15GB; T170A. I believe these are not composites or are permissible underwater.

Cylinders that come close are:
Luxfers 106W (Composite for underwater) 11.1L 300bar
Thunderbird aluminium 13.3L 228bar
Catalina C100 13.3L 228bar

You are unlikely to find a SCUBA valve that will fit a 25E or 17E connection, or any of the non standard thread sizes of M25x2, 3/4 NPSM and so on. There is good reason for the different thread norms, it is to prevent the wrong cylinder to be taken into an environment it won't appreciate.
There are tons of aluminium cylinders out there with a vastly bigger volume, but most won't be suitable for diving for one reason or another.


That will unfortunately not work. While the thread is also a G5/8", just as in the "DIN" connector, the BS341-3 #3 connector has a decidedly different geometry. The thread matches, but the BS341 expects a bullnose to be present on the regulator. These are for oxygen use, not SCUBA.

Many thanks - the T170A (and T188C) look like they could be good - but any idea about those threads?

I tried to find P2594D-S12LX & P2942M-S15GB but couldn't find them anywhere - not even with google. Do you have any links?

 

[Tanks A Lot]

The thread of the T170A is a 7/8"-14 UNF, for which SCUBA valves exist. I'm not aware of SCUBA valves for the 1 3/16"-12 UN thread, hence why I didn't mention the cylinder.
I do not have links to the P2594D-S12LX & P2942M-S15GB. All I know is the dimensions of them and that they are made by Luxfer:

Part #	Water Capacity (L)	Working Pressure (Bar)	Test Pressure (Bar)	Diameter (mm)	Length (mm)	Wall Thickness (mm)	Weight (Kg)	Thread
P2594D-S12LX	12.0	300	450	191	750	17.2	21.6	M25x2
P2942M-S15GB	15.0	232	348	204	720	13.7	18.7	M25x2

You won't find P2942M-S15GB made new, as it was made from 6082 aluminium, which suffered a similar flaw as 6351-T6. You might be able to source a used one somewhere. The P2594D-S12LX is made from 6061-T6.

 

[RedSeaDiver2]

The thread of the T170A is a 7/8"-14 UNF, for which SCUBA valves exist. I'm not aware of SCUBA valves for the 1 3/16"-12 UN thread, hence why I didn't mention the cylinder.
I do not have links to the P2594D-S12LX & P2942M-S15GB. All I know is the dimensions of them and that they are made by Luxfer:

Part #	Water Capacity (L)	Working Pressure (Bar)	Test Pressure (Bar)	Diameter (mm)	Length (mm)	Wall Thickness (mm)	Weight (Kg)	Thread
P2594D-S12LX	12.0	300	450	191	750	17.2	21.6	M25x2
P2942M-S15GB	15.0	232	348	204	720	13.7	18.7	M25x2

You won't find P2942M-S15GB made new, as it was made from 6082 aluminium, which suffered a similar flaw as 6351-T6. You might be able to source a used one somewhere. The P2594D-S12LX is made from 6061-T6.

OK many thanks - it sounds like you are totally clued up on all of this!

The L170A seems to be a composite over aluminium cylinder so that one is probably out. What I might do is email Luxfer and ask them if P2594D-S12LX is still available - perhaps sold under a different model number now.

 

[RedSeaDiver2]

I may have stumbled on a solution by accident - anyone ever used these? Made by Worthington - Carbon Dive 300

 

[MarkA]

I may have stumbled on a solution by accident - anyone ever used these? Made by Worthington - Carbon Dive 300

You know that these cylinders are not aluminium?

• Cylinders have a steel liner (CrMO-steel)
• Carbon fibre wrapping (cylindrical shell)

 

[RedSeaDiver2]

You know that these cylinders are not aluminium?

• Cylinders have a steel liner (CrMO-steel)
• Carbon fibre wrapping (cylindrical shell)

True - but they are a lot lighter than steels - which was the main thing that I was seeking. Unfortunately I haven't been able to find any full and empty buoyancy numbers yet.

 

[sea_ledford]

Why not just use more than one standard size bailout per person? While I get and love the joy of finding the exact correct thing for a job, I've also found that they tend to turn into useless albatrosses once the specific job is over. Standard sizes are standard for a reason.

I actually used to have sets of al100 doubles that were perfect for what I was using them for (deco diving on offshore platforms), but they are sub par for anything else.

 

[RedSeaDiver2]

Why not just use more than one standard size bailout per person? While I get and love the joy of finding the exact correct thing for a job, I've also found that they tend to turn into useless albatrosses once the specific job is over. Standard sizes are standard for a reason.

I actually used to have sets of al100 doubles that were perfect for what I was using them for (deco diving on offshore platforms), but they are sub par for anything else.

Because we are going to be kneeling on the sand doing underwater archaeology work we want to have the bailouts in a semi GUE style on the back - they won't be connected together or anything like that, but on the back gets them out of the way and leaves the arms totally free to move and it keeps the bailouts from potentially damaging anything. Its just a preference thing for this particular situation.