Propane Tank Fitting Standards?

Discussion in 'The Garage' started by P B G, Jun 3, 2012.

  1. P B G

    P B G Long timer

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    Anyone here familiar with the various threaded fitting types used on propane tanks?

    I have a number of tanks I use on my forklift, but I'd like to use them on my turkey frier instead of buying "blue rhino" tanks which cost more to refill than hitting the U-Haul.

    Unfortunately the couplers don't match up. Forklift coupler is brass, seems has a straight internal stub with rubber rings inside the female on the tank.

    On the turkey frier it has the plastic knob and the inner brass with the tapered nose.

    Are there standard names so I can search for adapters or hose couplers?
    #1
  2. rick505

    rick505 Adventurer

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    I hope you get a few more informed answers but I found this site that shows some pictures under fittings that might help you identify the various fittings

    Propane Warehouse

    Good Luck.

    Rick
    #2
  3. MCMXCIVRS

    MCMXCIVRS Long timer

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    The forklift tanks are designed to allow liquid propane to be drawn off rather than vapour and as such are completely incompatable with your frier. That's why the fittings are different, it prevents someone from accidently using the liquid tank for a vapour appliance. The result would be a very rapidly cooked turkey, but finding where it landed after the explosion would be the challenge. :eek1
    #3
  4. P B G

    P B G Long timer

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    Interesting, are there evaporator fittings to permit liquid expansion outside of tank?

    Is it possible to utilize one of the other threaded plugs on the tank to install a different fitting? I would assume the tanks can be either way, liquid or gas?
    #4
  5. DirtDabber

    DirtDabber cultural illiterate

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    Forklift bottles have a dip tube to draw off liquid gas. Grills work off vapor.
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  6. troidus

    troidus Long timer

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    So the trick would be to run the bottle inverted, then? All the forklift bottles I've seen have been mounted sideways, so maybe there's a This Way Up notation on them somewhere.
    #6
  7. fxstbiluigi

    fxstbiluigi crash test dummy

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    I have discovered that it's usually best not to try to out wit ( by observation ) some one that has engineered a safty margin, even as modest as a few letters stamped in a tank, into something that has the potential to really make a mess out of your day not to mention your house. I haven't tried this yet so I'm unsure but Google propane cylinder explosion.
    #7
  8. RVDan

    RVDan Long timer

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    If the propane cylinder has an outlet marked "vapor" you can use it. If it doesn't, don't even try. Running a half filled bottle upside down would work as long as the tank doesn't have an auto stop fill valve on it, but it would be dumb.
    #8
  9. D.T.

    D.T. Difficult but useful

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    Backyard and or hillbilly engineering is a bad idea when it comes to Propane tanks...

    Not worth it to save a few bucks in my opinion.
    #9
  10. P B G

    P B G Long timer

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    I don't want backyard hillbilly engineering, usually when there is an issue there exists an engineered solution for said issue.
    #10
  11. fxstbiluigi

    fxstbiluigi crash test dummy

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    The propane tank at work has a fitting for filling forklift trucks?
    There is an adapter that will enable you to fill tanks with the valve that is compatable with BBQs, Travel trailers and such.
    #11
  12. jbhawley

    jbhawley WTF- Gus?

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    Ahem...
    After reading this post and snickering a bit I decided it was time to chime in. Let me preface my post by stating that I worked as an LP Gas technician back in the 90s at a local LP Gas Company. Needless to say...I know way too much about LPG.

    First, the fork lift tank is just a propane tank. It is probably made from aluminum rather than steel for weight. No biggie. It does not matter. What matters is the tank fitting. Most likely you have this type of valve. Its called a Forklift Service Valve.
    [​IMG]

    Attached to this valve is probably an adapter that looks like an OPD fitting. IT IS NOT HOWEVER! This valve/fitting is a 1 1/4 ACME. The OPD is a 1 5/16 ACME.
    But all is not lost.
    [​IMG]

    LPG powered engines may use the vapor or the liquid. You can easily tell by the tank positioning when the tank is on the forklift. If the tank is laying sideways then its most likely liquid powered. If the tank is vertical then its vapor powered.

    Yes you "can" use the forklift tank as a turkey frier tank. First...sit the tank up right so the valve is on the top. While in your yard and away from any ignition source, slowly open the valve. You should get LPG vapor. If so then you are good to go. Now all you will need is an adapter for the tank valve.

    Too much info coming now...
    Most post - mid-90s LPG tanks (non-motor fuel tanks) have a OPD (overflow protection device) valve. This allows/protects the tank from being overfilled. Within the tank and attached to the valve is a float of sorts that one lifted stops the LPG from entering the valve when the tank is being filled. Older tanks have the old POL valve.
    FYI...these are all LEFT handed threads...no righty tighty, lefty loosely...its the other way.

    POL Fitting
    [​IMG]

    OPD Fitting

    [​IMG]

    The POL valve looks like this.
    [​IMG]

    The OPD valve looks like this
    [​IMG]

    The beauty is that the OPD valve as internal thread that will allow the POL fitting to screw inside. The POL fitting...not so much. An OPD fitting will not screw into a POL valve. So if your tank has the OPD valve then you can use either the older POL fitting or the newer OPD fitting. The fitting is what is attached to the hose...so to speak.

    Now which adapter do you need.
    If you have the OPD valve then you are good to go to connect to your frier. It is 99% unlikely that the forklift tank will have an OPD valve.

    If you have the POL valve then you need an adapter such as this:
    http://www.propanewarehouse.com/qccfittingdetail.asp?ID=3005
    It is also 99% unlikely that the forklift tank will have an POL valve.

    If you have the forklift fuel valve with the adapter as show above then you can do this.
    Keep the adapter on the valve.
    Buy one of these which will screw on the forklift tank valve/adapter.
    http://www.propanewarehouse.com/forkliftvalvedetails.asp?ID=6015

    [​IMG]

    Also get one of these which will screw onto the above adapter.
    http://www.propanewarehouse.com/qccfittingdetail.asp?ID=3031
    From this adapter your frier OPD female fitting will fit...the one attached to the hose.

    [​IMG]

    So when all is done you will have a contraption that is Valve > adapter > adapter > adapter > hose.
    It will work and all the parts are engineered to fit together properly. Is it worth the cost? Doubtful.

    Again, this is very much do-able, but to be frankly honest, by the time you put in the time and money to get all the parts you could buy you a regular frier tank for 50$ and not have to monkey with all these adapters.
    #12
  13. D.T.

    D.T. Difficult but useful

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    Now we get an expert. Just what I figured. All those adaptors are going to cost $50 bucks anyway. Which you can buy a Rhino tank for the same price.

    Unless you can find one for cheap somewhere.
    #13
  14. 2speed

    2speed Puching adventurer

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    What if you wanted to use a Rhino tank on a liquid powered forklift?
    #14
  15. DirtDabber

    DirtDabber cultural illiterate

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    on a treadmill.....
    #15
  16. jbhawley

    jbhawley WTF- Gus?

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    Sure it will work. You will have to change the tank valve from the standard OPD valve to the Forklift fuel valve and get the adapter to fit onto that particular valve that allows connection to the forklift hose. Plus find a way to mount the tank to the forklift. Swapping a valve is easy....getting the tank to cooperate is the challenge. Ever try to hold a round tank stationery while putting torque on it trying to also turn it? We (my old LPG company) had a special vise we used to hold the tanks and then a special tool to install/remove the valves without damage.

    Again...most folks do not try to use tanks that are not made for the apparatus. Its just more cost effective to have the proper equipment. FWIW...I would rather have a forklift tank modified to use the OPD valve as the tank is aluminum and will not rust or corrode.

    FYI the Rhino type tanks that you get off the rack are (by state and federal law) required to be pressure tested before each refill. Most companies also paint the tanks of needed. This assures that you are getting a quality tank each time. How many of us...myself included...take a used and abused tank and exchange for a good tank? If you have a good tank (one you purchased outright) you can usually save 1/2 price by tanking the tank to a local LPG dealer and have them refill that tank and give it back to you. Usually this is done while you wait...10 minutes or so. Sure you done get a shiny new painted tank each time...but if the tank is in good shape...it will save you some $$$$.

    Most Forklift tanks are more slender than the typical Rhino tanks.
    Rhino type tanks that you get "off the rack" are 20#
    Forklift tanks come from any size 10# to 40#
    The weight is the amount of LPG within the tank...so a 20# tank hold 20# of LPG which also equals 5 liquid gallons.

    See I told you all that I know way too much about LPG...I guess somethings I will never forget. :D
    #16
  17. jbhawley

    jbhawley WTF- Gus?

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    I did a bit more digging and found a easier solution to the OPs issue. The cost of the parts is still about the same as buying a Rhino tank...I have edited my post with the new info.

    Thanks
    #17
  18. 2speed

    2speed Puching adventurer

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    Where I am it's easier to get Rhinos than fork lift tanks, so I was wondering if you could just hook them up.

    Obviously more involved with a valve switch.....
    #18
  19. troidus

    troidus Long timer

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    I read somewhere not long ago that the typical refilled tank purchased from a self-serve rack has only 15# of gas in it, despite being a "20 pound" tank, with the discrepancy explained as a "safety" feature. I think if I owned my own tank I'd want to have it refilled, rather than swapped, since I'd know its history.
    #19
  20. jbhawley

    jbhawley WTF- Gus?

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    Safety...HAHA....profit margin....possibly.
    LPG tanks are supposed to be filled to only 80% of capacity. Meaning 80% full is considered full. So a 20# tank will hold 5 gals of LPG but the tank itself is actually closer to 6 gal capacity. This allows for expansion of the LPG.

    If your Rhino type tank has this valve (below image). Then you can check to see if its full when purchased. With the tank upright in its normal position turn the little knob on the side of the valve. If liquid comes out then its filled properly and has the aforementioned 80% of LPG. If not then wiggle (slosh) the tanks around slightly to get the liquid to come out of the port. From this little knob/port there is a dip stick, of sorts, that extends into the liquid (bottom) of the tank. This knob is only hand tight.

    If the tank does not have this type valve then it was filled by weight. Somewhere on the top portion of the tank, near the valve, is stamped the empty weight of the tank...usually around 18-22#...add 20# for the LPG. You can weigh to make sure you are actually getting your moneys worth. So add the empty weight to the gas weight for the total. Should be around 40#...but you gotta know the empty weight first. FYI some of the older tanks we had to refill did not have a stamp or it was rubbed off and unreadable...we would just fill the tanks to 40# of scale weight.

    If a tanks has this knob on the valve then they are supposed to be filled using the knob...basically attach the fill hose > turn the know to open > begin filling the tank > once liquid starts to come out from the knob port stop the fill flow. If the tank doesn't have the fill knob then it has to be weighted on a scale. Any tanks over 100# (23 gal) will have the fill knob as they are too big and bulky to weigh. The large tanks at your house for home heating have this type valve...as this is the method the LPG delivery guy uses to fill your tank. Also your home tank, if larger than 100# will have a gauge. Notice the next time its filled, it should only be at 80% or so...maybe 85% at best.

    [​IMG]
    #20