Visit our Popular Forums

Terra Nova · 25-03-2014, 22:40

Quote:

Originally Posted by boatpoker

That's not quite what the standard says. 316L and 317L are approved at a minimum thickness of 1.9mm.

Table IV, "NOTE 2" restricting the size to 20g refers only to the lighter approved gauge of 0.79mm.

ABYC H-33 Diesel Fuel Systems...

"Table I - Fuel Tank Corrosion Resistance Requirements
Material
Stainless Steel (6) 316L
notes
6. Stainless steel tanks shall be cylindrical with domed heads and a capacity of less than 20 gallons."

That is exactly what the requirement states--no qualifier.

This is required for safety reasons due to corrosion problems with stainless diesel tanks.

boatpoker · 26-03-2014, 00:41

Quote:

Originally Posted by Terra Nova

ABYC H-33 Diesel Fuel Systems...

"Table I - Fuel Tank Corrosion Resistance Requirements
Material
Stainless Steel (6) 316L
notes
6. Stainless steel tanks shall be cylindrical with domed heads and a capacity of less than 20 gallons."

That is exactly what the requirement states--no qualifier.

This is required for safety reasons due to corrosion problems with stainless diesel tanks.

Sorry, you are incorrect. 316L and 317L are permitted without size restriction at 1.9mm. You will have to read it again. I have copied the whole page and highlighted the "Notes" below Figure IV.

This is from ABYC H-33, Diesel Fuel Systems, July 2010, Page 18. The latest edition of that standard

boatpoker · 26-03-2014, 01:04

H-33 Page 18 in pdf.

Don't know if this will work, I've never tried to post a pdf before.

Terra Nova · 26-03-2014, 06:59

Poke--you'd better read it again. Nowhere does it contradict the requirement spelled out in note 6. "Stainless steel tanks shall be cylindrical with domed heads and a capacity of less than 20 gallons."

boatpoker · 26-03-2014, 08:24

Quote:

Originally Posted by Terra Nova

Poke--you'd better read it again. Nowhere does it contradict the requirement spelled out in note 6. "Stainless steel tanks shall be cylindrical with domed heads and a capacity of less than 20 gallons."

Is it just my computer or can you not see the highlighted "NOTE 2" ?

"Cylindrical stainless steel tanks with domed heads and a capacity of less than 20 gallons are permitted to use this lighter grade steel".

Cheechako · 26-03-2014, 08:40

Quote:

Originally Posted by boatpoker

Sorry, you are incorrect. 316L and 317L are permitted without size restriction at 1.9mm. You will have to read it again. I have copied the whole page and highlighted the "Notes" below Figure IV.

This is from ABYC H-33, Diesel Fuel Systems, July 2010, Page 18. The latest edition of that standard

Well... either way, hopefully you guys get the picture that ABYC is not that fond of SS tanks!
I agree if the world is perfect SS is OK. Unfortunately it's not... one has only to remember back to all the posts about tanks gone bad to realize that. Up high and dry..yes. in the damp recesses no. Problem is a tank has to be supported somehow... and wherever that occurs is a damp wet oxygen depleted corrosion field.
The problem isnt just a bunch of owners... it's the manufacturers too.

boatpoker · 26-03-2014, 08:43

Quote:

Originally Posted by Cheechako

Well... either way, hopefully you guys get the picture that ABYC is not that fond of SS tanks!
I agree if the world is perfect SS is OK. Unfortunately it's not... one has only to remember back to all the posts about tanks gone bad to realize that. Up high and dry..yes. in the damp recesses no. Problem is a tank has to be supported somehow... and wherever that occurs is a damp wet oxygen depleted corrosion field.

I don't want anyone left with the impression that ABYC has anything against stainless steel tanks. Having taken their Corrosion Analysis course and their Standards Certification course I can affirm that is not what they teach.

Terra Nova · 26-03-2014, 10:27

Quote:

Originally Posted by boatpoker

Is it just my computer or can you not see the highlighted "NOTE 2" ?

"Cylindrical stainless steel tanks with domed heads and a capacity of less than 20 gallons are permitted to use this lighter grade steel".

How can you possibly read into that highlighted sentence that it is OK to build stainless tanks of any size?

boatpoker · 26-03-2014, 11:30

Quote:

Originally Posted by Terra Nova

How can you possibly read into that highlighted sentence that it is OK to build stainless tanks of any size?

If you look at figure IV where it lists 316L and 317L as approved materials you will note that there is no size limit noted at all, neither is there anywhere else in the standard as long as all other requirements for design, construction, welding and installation as noted elsewhere in the standard are met.

That highlighted sentence simply permits use of a thinner material if your tank is less than 20 gallons.

Terra Nova · 26-03-2014, 13:46

Then you would have to completely ignore their note 6.
"Stainless steel tanks shall be cylindrical with domed heads and a capacity of less than 20 gallons." There is no mention, here, of thickness or any other qualifier.

Seems perfectly clear to me, <20 gallons.

boatpoker · 26-03-2014, 13:57

Quote:

Originally Posted by Terra Nova

Then you would have to completely ignore their note 6.
"Stainless steel tanks shall be cylindrical with domed heads and a capacity of less than 20 gallons." There is no mention, here, of thickness or any other qualifier.

Seems perfectly clear to me, <20 gallons.

I don't know what you are reading but there is no "Note 6".
Is your copy from 1975 perhaps ?

I have posted the entire ABYC Diesel Fuel Systems H-33 here. Please review and tell me what page and line I can find "NOTE 6"

**minaret** · 26-03-2014, 14:47

Quote:

Originally Posted by Terra Nova

Then you would have to completely ignore their note 6.
"Stainless steel tanks shall be cylindrical with domed heads and a capacity of less than 20 gallons." There is no mention, here, of thickness or any other qualifier.

Seems perfectly clear to me, <20 gallons.

This would disqualify the majority of the tanks I have seen.

Igotnuthin · 26-03-2014, 15:11

Fortunately MY steel tank is up off the boat and attached to a bulkhead.......and I too can read "Cylindrical stainless steel tanks with domed heads and a capacity of less than 20 gallons are permitted to use this lighter grade steel".