Fuel tanks and delivery lines

Discussion in 'Furnaces and their construction' started by OMM, Aug 17, 2019.

  1. OMM

    OMM Silver

    No I don’t need seven psi. I could probably get away with three PSI, But I didn’t want to regulate it. And I would have to go with a 5/16min or bigger delivery line.

    At one of my part-time jobs I do maintenance for the pneumatics. I get all their old compressors and the last two I told them to just throw out, as I have two in the boneyard already (and now they have another one for me just like these ones but in blue). The tanks are only 2.5 gallons each or 5 gallons per compressor. Maybe something old to be come new again. Second life. I think I just need to bite the bullet.

    BD10A15F-71C9-47DB-93E6-4B50512E75A7.jpeg

    I also dug up in my boneyard two Whitney needle valves. They are not really needle valves, more of just a taper. They do need a good cleaning .
    5AB4B66C-BB94-49B5-A465-9F04BEAF51BC.jpeg
     
  2. Jason

    Jason Gold

    Flag pole. Problem solved. Those tanks look like winners.
     
  3. OMM

    OMM Silver

    Jason I was just thinking that. That will really concern neighbours with a jerrycan hanging 20 feet up a flag pole with the roar of fire and mushroom clouds. It would be smarter just to fill the flagpole and pump the fluid up with a ball valve at the bottom. Lol
     
    Tobho Mott likes this.
  4. Petee716

    Petee716 Gold Banner Member

    Those compressors look like a winner. You get a head start on the fittings and it already has a carry handle. (Although the flagpole/fuel tank idea is about the most novel thing I've heard in a month!)

    Pete
     
    HT1 likes this.
  5. HT1

    HT1 Gold Banner Member

    Pretty sure I mentioned Compressor tanks before, the Only issue is there is no easy way to fill them... Well a transfer pump, but that definately is not KISS

    V/r HT1
     
    OMM likes this.
  6. The chill is caused by pressure reduction. In the regulator, the pressure drop chills the regulator but does not affect the tank. The tank is chilled by evaporating liquid in the tank. The energy store in the liquid and that which can come into the tank from outside determine how the tank temperature will drop. With a small tank you are removing half or more of the propane. With a large tank, you would have to remove half or more to get the same effect. My 250 gallon tank will last 100 melts or more and there is no noticeable temperature change. If you have large tanks available, use them.

    This is a very dangerous misconception. Propane is heavier than air and will flow along the floor or ground a long way. In a home, it will flood the floor with vapors the often ignite at a pilot light.

    I like propane. Cost me $1.52 per gallon to fill my tank yesterday.
     
  7. OMM

    OMM Silver

    Yes you are right. There is no easy way to fill them. I am going cut/separate the two. Cut off and weld shut all the holes, Add a handle, Weld up a fill spout for 3/4” (or 1”) NPTF. Then go to 3/4” MHT. From there I can cap it off, fill it easily and/or use it as a jerrycan.

    The tank on the left that has the 1/2NPTF also has at the side of it, in the middle a 1/4NPTF that was the old bleeder valve. It to will have to be filled (or plugged).

    I’ll see how thick the wall thickness is. I do plan on drilling and tapping two holes in the side of the tank for 1/8 NPTF for a site glass.

    The two small pipes that attach the two tanks measure OD of schedule. Hopefully they are schedule 40.

    If everything works out as I plan, I will be able to pressure transfer fluid using the blower. It might be slow at half a litre per minute, but faster then the suggested burn rate. I’m going to be pressure syphoning through the fill nozzle with a
    B-Vent.

    F9ADDC16-8D00-474E-B16C-067AB80E0086.jpeg
     
    Last edited: Aug 23, 2019
  8. PatJ

    PatJ Silver

    You can weld a fill cap/plug onto them, but it is still not that easy to fill, but I do use this tank, and fill it with a 5 gallon fuel container with spout.

    If you are not good at welding thin wall steel, don't attempt this.

    Edit:
    I did not have all the fittings connected in this photo, but you get the idea.

    rIMG_4197.jpg
     
  9. PatJ

    PatJ Silver

    Here is a photo of the tank hooked up.
    I pressurize the tank to about 10 psi.
    The fuel pickup tube is the copper line, and it goes down to within about 1/2" of the bottom of the tank.
    The copper line is connected to the black fuel line, which runs over to the burner.

    The valve releases the tank pressure when the melt is complete.
    I did some photoshopping on this since I had a LOT of junk in the background.

    Be sure to test the welds with some compressed air (30 psi perhaps), and soapy water to check for leaks.
    I neglected to do that on this tank, and so I have some pinhole leaks at the cap weld.
    The leaks do not affect the tank function luckily since they are so small, and since the welds are at the top of the tank, fuel does not leak out.

    rIMG_5008.jpg
     
  10. Jason

    Jason Gold

    Thin?? You should try disposible refrigerant tanks. Now those are thin! Thank god you guys taught me how to braze with bronze and flux. I'm not pressurizing them, but they dont leak a drop of jet-a. That stuff seems to leak easier than anything I've ever seen.
     
  11. OMM

    OMM Silver

    Pat, are you using Arc or Mig?

    I will be tool welding it with TIG SS.

    I plan on pressure testing them to their vessel certification of 125 psi when my welding is done. I will lest them be charged to 155 psi (for 30 minutes) (which is the max output of my big compressor). Then I will adapt the MHT (male hose thread) and pressurize test it, submerged in water to see if there is a shortfall with MHT O-ring.
     
  12. Jason

    Jason Gold

    155psi is no joke.:eek: While I don't doubt your resourcefulness, you sure you have to welding skills to do this? GTAW is the obvious choice to me, but you ask pat SMAW or GMAW?
    If these letters are greek to you, please stop now buddy.;)
     
  13. Jason

    Jason Gold

    I see your edit. TIG SS is a much better plan. ;)
     
  14. OMM

    OMM Silver

    I TIG (GTAW) almost everything. I Arc and Mig, but I am mainly a tool welder.
     
  15. Jason

    Jason Gold

    You're good to go then. I haven't touched my shitty old craftsman mig in years. I tig everything. Doesn't bother me one bit it's slow. Tried stick once, learned why they
    call it stick welding. It STUCK to everything I got near with it. Including my dads carpenter square! He then STUCK his foot in my ass. :oops:
    What mom brings home a buzz box from a garage sale for her 10year old idiot son? MINE DID! lol...
     
    OMM, Peedee and Tobho Mott like this.
  16. OMM

    OMM Silver

    Jason, curious what are your expenses in your parts for argon and argon tanks. Here it cost me $95 to fill my 80 CF tank. I Purchased my tank for $350 which I am able to return with refund. Now, I just pay the fill price in a swap.
     
  17. Jason

    Jason Gold

    Wow.. thats sky high. My 80 cost me 220 or so at airgas. I tool it to another store and traded it for a 120cf for just 35bucks. A fill is around 35 I think. Im due for a fill soon so I'll have to get you a more accurate price later. I usually fill twice a year. You need a new supplier or a new country to live in.
     
  18. HT1

    HT1 Gold Banner Member

    welding supply's have an insane sliding price scale. volume purchasers get a HUGH discount over retail... ( I freelance at several Businesses that Use Gas ) so I get to see different peoples bills the guys at the welding suppl finally had to start giving me a great price since if they quoted a retail price I would whip out a receipt and embarrass them. this is also True for Propane . I get Propane for food trucks at half the retail cost .

    you will also see shortage bleed, there is a Helium shortage, so the Prices of all gasses will climb


    V/r HT1
     
  19. Zapins

    Zapins Gold

    Yeah I think I paid 260 per tank (80 or 120cfu? the big 4 foot ones), and its between 45 to 60 to fill with argon depending.

    I'd like to get a huge propane tank and run off that. Would be cheaper and easier than bbq tanks. Ugh.
     
  20. I hope you fill it with water before testing. The energy in a small pneumatically tested vessel will easily kill should you wind up welding across a hard spot caused by deep drawing the vessel. It can split and rupture and make a real mess. Filled with water all it does is spray and maybe put an eye out. Using air to get the water up to pressure is fine. E309 would be a good filler rod. Code require pneumatic tests be done to 110% of operating pressure, not 150%.
     
    dennis likes this.

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