Stainless Steel gas tank.

[Stainless1]

Mike, I suspect you already know a properly constructed vent will also serve as the tip-over valve.
Keep up the good work 

[tauruck]

I didn't know that but with you guys all
helping I'm learning. Thanks B.

Now you've got me thinking....... I had
something like that here, there was a ball in a cage?.

I'll have a look.

[roygoodwin]

Here's a link to a guy who has built 2 stainless gas tanks  <  http://www.midlana.com/Diaries/Current/ >  Under 1 Feb 2015  "....The sheet metal shop was unable to close the sheet, meaning three long weld seams. Fearing the extreme warping that happened with tank V1.0, it was welded in 1" increments, moving back and forth, side to side, and was rewarded with virtually no warping. Seen in the pictures below is the comparison of the tanks V1.0 and V2.0. Tank V1.0 warped, bending the top 4" section of 0.065" stainless on edge nearly 1.5" over 44". I can hardly imagine the enormous force needed to bend a 4" thick section of stainless! Tank V2.0 shows practically no warping at all - very happy about that. ....."  Maybe there will be something you'll find useful.

Roy

[tauruck]

Roy, thank you.
Perfect.

[tauruck]

Here's the latest update on the tank.

I found a sponsor. With my project being an
underfunded roller coaster I try get help where I
can and if that fails I have to try do it myself.

I sent out 5 proposals and got two positives.
I told the guys that the tank was a complex piece
that need radiused corners and welding needed
back purging etc and if that was a problem they could
supply materials and I'd do it.

They never went for that and Latham Engineering Africa
is going to do the tank to spec.
The guys are high tech and know far more than I do.
Check them out.

http://www.lathamengineeringafrica.co.za/

Divine intervention again.

[SPARKY]

I am not much one for depending on ball check valves--- a vent line properly done has very, very little chance of fuel getting out; be sure and vent the front most corner so that under hard acceleration the fuel doesn't ride up and cover the vent.

[tauruck]

Will do. Thanks Sparky.

What size line?. -10?.

[kiwi belly tank]

Double up on the weld-in's Mate. You can plug them if you don't use them, a lot easier than trying to add more later when you go to that 600 incher.
  Sid.

[Stainless1]

Our vent uses a spring loaded ball as well as a rollover line design.  When designing the line, think about the vehicle coming to rest, sides or top, you don't want fuel coming out of the vent line. 

[RaceEngineer]

here is a link to a typical tip over valve (check ball).  this mount in the tank (usually access thru the filler cap to install, or pre install during fabrication of tank if you what to mount vent near the front of the tank).  the line connecting to the tip valve should have a loop or coil in it to minimize siphoning.

 http://www.summitracing.com/parts/sum-g3114/overview/

hope this helps

[tauruck]

Thanks all and especially RaceEngineer.
That's the one. I'll order it tomorrow.
This component is a critical part and all the help and advice is invaluable.


I'm not known for being a sissy but fire really scares me.
Just watch the overkill on this one. I keep saying this and
guys are probably tired of me but without the members here
this car wouldn't be, period.

Mike.

[Geo]

I have a set of drawings when I asked for help with venting my fuel cell and I have yet to find them.    Here is some discussion by JackD that describes the routing that works for landing on every side except nose which is not likely. I ran mine out the top center access plate, to the left and down that side, across the bottom, up the right side and continued up and forward to meet the factory vent system running to the front of the car. In the event of not being on it's wheels no fuel will run out the vent from a full tank. The level in the vent line will never exit as there is always more line higher than the level in the tank. I used 1/2 inch aluminum tube from the home center and bent it with an external spring and electrical conduit bender then flaring the ends to AN fittings.


JackD
Check valves are a good start but if you route the vent line out the top, around to the right and across the bottom to the left, what part is not on top above the fuel level in any rollover upset ?
Even if you stand it on it's nose, with the line routed from front to back as it goes around it will work where a check valve won't. 

I have a check valve at the tank and hope to never test the system.

Geo

[tauruck]

Thanks Geoff, good advice.

What size vent lines should I use?.

The guys building my tank want the weld in male bungs
and I only have Dash 10 here.
Should I use those or go to an 8?.

[Ron Gibson]

Only flowing some air to equalize pressure, a #4 or#6 should be sufficient for gas, #6 or #8 for fuel.

Ron

[tauruck]

Ron, thank you.

I'll be running Ethanol and have some #8.
I'll go with that. God Bless.