Question True Capacity of Faber FX100DVB

[Txredneck]

I'm perplexed upon the true capacity of the Faber High Pressure FX100DVB steel tank. Faber Blue Steel specs say this tank is 100cf capacity. but it's water capacity is listed at 12.9 liters, with max fill pressure of 3442psi. This would give it a true capacity of 107cf.


The Worthington X7-100 gives a true capacity of 99.5 on their specs, a water capacity of 12.2 liter, max fill 3442psi. 12.2 liters at 3442 psi would be 101 cf.


Does anyone know, is the Faber FX100DVB actual capacity 107cf? Is the 12.9 liter water correct. I do know both tanks have same OD, and Faber is definitely a couple inches taller as well as Faber is 1.2 pounds heavier which would be just about right for the longer length even with same wall thickness.


Is the Faber FX100DVB actually a 107, not a 100?

 

[mala]

the faber is 2992 lts at 232bar.

im only 52 so cf is a bit before my time.

 

[Txredneck]

2992lts is 105.67 cf
232 bar 3365 psi

Definitely more than the 100cf imperial on their specs.

 

[mala]

faber work in the 21st century.

so that's bar and litres.

if anyone quotes in cf I would take it with a pinch of salt.

 

[Txredneck]

faber work in the 21st century.

so that's bar and litres.

if anyone quotes in cf I would take it with a pinch of salt.

Faber's (Blue Steel) website quotes in cf

Blue Steel Scuba - Cylinder Specs

---------- Post added January 31st, 2014 at 03:20 PM ----------

Looking at all the Faber dealers overseas (Europe, Australia...) specs of the bottle show 12.2 liter. So now I wonder if these bottles (Faber Blue Steel) are 12.9 or 12.2 liter...

 

[BRT]

They are definitely larger in outside dimensions.

 

[Txredneck]

They are definitely larger in outside dimensions.

According to dimensions on Faber Blue Steel website, they are larger outside than BOTH the Worthington X7 100's and the European Faber 100's. Faber Blue steel, according to specs given, are 7.25 diameter whereas European Faber is 7.0 diameter. European Faber is also about an inch shorter that Blue steel, according to specs given.

 

[Txredneck]

Photos of tanks. Both steel, both 3442 psi, both have same outer circumference, in photo both tanks are wearing identical boots, both state 100 cf in specs

 

[cbrich]

This is what get for the volume of the Faber HP100 with DOT/TC Exemption. Faber-italy.com (Divefaber.com) list the working pressure the DOT/TC exemption cylinder at service pressure of 237 bar, nominal water capacity at 12.9L (this is same on Blue Steel LLC.)

Faber HP100 specs:
Working Pressure: 237 bar
Nominal Water Capacity: 12.9L
Outside Diameter: 184mm
Empty Weight: 15.6 kg

Converting 237 bar to Atmosphere: 233.9008 atm
Convert 12.9L to Cubic feet: 0.4555592 cf

Now multiply
233.9008 atm * 0.4555592 cf = 106.5557 cf.


Take a look at XS Scuba (Worthington Cylinders), starting off with Metric System on this one too, since we are converting to Imperial system. Service pressure of 230 bar, and nominal water capacity of 12.2L.

Worthing HP100 specs:
Working Pressure: 230 bar
Nominal Water Capacity: 12.2L
Outside Diameter: 184mm
Empty Weight: 15.0kg


Convert 230 bar to atmosphere: 226.9924 atm
Convert 12.2L to cubic feet: 0.4308389 cf

Now Multiply
226.9924 atm * 0.4308389 cf = 97.7972 cf

So the Faber is almost 9 cubic feet more air than the Worthington HP100, and only 0.6 kg (1.32 lbs) heavier.


References:
Faber Italy: Faber Industrie: the global supplier of steel cylinders for high-pressure gases Established in 1972, Faber Industrie has grown rapidly to become the leader in the production of seamless steel high-pressure cylinders for the storage of gases. All over
Dive Faber: Faber Industrie
Blue Steel LLC. (US Distributor for Faber): Blue Steel Scuba - Cylinder Specs
XS Scuba: XS Scuba Worthington Steel Cylinder Specifications

 

[Txredneck]

Faber HP100 specs:
Working Pressure: 237 bar
Nominal Water Capacity: 12.9L
Outside Diameter: 184mm
Empty Weight: 15.6 kg

Converting 237 bar to Atmosphere: 233.9008 atm
Convert 12.9L to Cubic feet: 0.4555592 cf

Now multiply
233.9008 atm * 0.4555592 cf = 106.5557 cf.


Take a look at XS Scuba (Worthington Cylinders), starting off with Metric System on this one too, since we are converting to Imperial system. Service pressure of 230 bar, and nominal water capacity of 12.2L.

Worthing HP100 specs:
Working Pressure: 230 bar
Nominal Water Capacity: 12.2L
Outside Diameter: 184mm
Empty Weight: 15.0kg


Convert 230 bar to atmosphere: 226.9924 atm
Convert 12.2L to cubic feet: 0.4308389 cf

Now Multiply
226.9924 atm * 0.4308389 cf = 97.7972 cf

So the Faber is almost 9 cubic feet more air than the Worthington HP100, and only 0.6 kg (1.32 lbs) heavier.


References:
Faber Italy: Faber Industrie: the global supplier of steel cylinders for high-pressure gases Established in 1972, Faber Industrie has grown rapidly to become the leader in the production of seamless steel high-pressure cylinders for the storage of gases. All over
Dive Faber: Faber Industrie
Blue Steel LLC. (US Distributor for Faber): Blue Steel Scuba - Cylinder Specs
XS Scuba: XS Scuba Worthington Steel Cylinder Specifications

To be fair to Worthington, their HP100 is the same working pressure as Faber Blue Steel. Both bottles pictured are stamped "3442" working pressure, neither is stamped in Bar pressures.

I did some rounding. But using 3442, I got 100.77 for the (hence 101 cf) and the same you calculate on Faber rounded to 107.


I was just asking this so as to know for planning dives. The smaller tank will be my 13 yo son's as I use a little more air than he. As such, most of the dive planning will be based upon my tank and using 100 cf as planning #, so I was curious if I'm missing something here. But it certainly appears this is a 106.7 cf tank, which is a good safety margin...

Thanks for your reply!