Gas forge question

RossGa

New Member
There is a guy who is selling a 100 gallon propane tank for $100 that I want to use for my new forge that I am building. My question is: how long would 100 gallons last? I understand that it depends a lot on burner types/size of forge, but a ballpark estimate would be great. Thanks.
 
I run 20# tanks on my forges and they seem to last several hours, but I've never really kept track. A 100# tank is going to last for quite a while. You'll do a lot of forging between fill-ups.

Doug
 
It's all gonna depend on the pressure you run your burner at too, I also run mine on 20 pounders and when running wide open at 20 psi in the summer it's about an hour, but most of my forging I run at about 5 psi and I can get quite some time out of a cylinder. A 20 pound cylinder IIRC is only about 5 gallons so 100 gallons would last quite some time
 
If your shop/work area can accommodate the 100 gallon tank, and you're in it for the long haul, then it is certainly worth checking into.

Several years ago I lived on a small farm. All heat for the house (stove, water heater, furnace) was supplied with a 500 gallon tank. Disregarding lifestyles, home efficiency, "rough winters", etc., we averaged about one-and-a-half tanks annually.

We all have different applications and conditions, but what has been said by the others should hold true- a 100 gallons of propane should last you quite some time.
If you can get a rough idea of how long a little 20# (5 gallon) tank will last you, simply multiply by 19 or 20 for rough estimate on the large tank.

For me, the major advantage of a large tank is not the longer interval between refills, but the ability to handle freeze-up.
Like most of us, I use the 20# cylinders.
But if I'm really puttin' out some serious heat (large venturi burner/high pressures), the small tanks will ice to the point that pressure cannot be maintained.

There are a few solutions to the icing problem.
Some people place the tank in warm water; I have done that before and it's so much of an inconvenience that I don't care to repeat the process.
Another option is to connect more than one tank, and this is what I currently do. Two or more tanks (I use three) connected via a manifold will alleviate the icing problem, but all tanks will empty at the same rate. More connections to mess with, and more chance for something to go wrong. My largest complaint with the multiple small tank approach is the floor space used.
And then of course you have the option of drawing from one larger tank.

But for me (and I suspect most of us), the small tanks are about convenience. We want the ability to place the forge and the tank in different locations so as not to have a mile of gas hose laying across the floor. Plus, it is more convenient to refill the small tanks. Most areas have more serious regulations pertaining to transportation of tanks much larger than 20#; I think 40# is the "limit".

Of course, by the time we get to 100 gallon tanks most of us are considering delivery service from the gas company.:3:
(An empty 100 gal tank should weigh close to 300#, and it will hold over 400# of propane. Somewhere around 700# total +/- when full.)
My problem is that my location doesn't have easy access for a fuel truck, and I don't want to run lines underground from another area. If I went to that trouble, I would get a 500 gallon tank and use it for everything.

If you have the means to facilitate refills, and your shop area can accommodate it, a large tank is a good choice.
With the large tanks the best thing to do is locate the tank in a separate area; most folks build a separate "room" on the outside of the shop and run hard lines around the walls inside. Various hookup locations around the shop (with shutoff valves at each point).

Weigh the options, and decide what you need.
As always when dealing with used tanks, make sure the tank is safe to use before plunking down the cash. $100 for a tank that size is a great deal if it's in usable condition.
 
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Just for reference I paid 123.00 for mine, I got it, last year and still running on the same tank, now I don't forge everyday, and here lately have went months with out firing it up, so I may not be a good indicator of how long a tank will last, I generally will forge out 2 to 4 blades and then start working on the finish work on those, PLUS, I'm stingy with the gas, as soon as I'm done I cut it off.

I think there is something being left off here, isn't there something about the pressure of a 100# tank being better than that of the smaller tanks?
The inconveince of refill isn't all that bad, I put mine in the back seat of my Hundai Elantra! It actually fits! Rex
 
Rex,

You talking about a 100 pound tank? That would be somewhere in the range of 25 gallons.
I considered one of those, but one of the contractors at a job site got cited for violating transportation code because he didn't have it "upright and chained".
Maybe it's just a local quirk for the authorities that be. I think we're allowed to go up to 40# (10 gallon) tanks without having to do anything "special".
Nevertheless, I'm still considering going up in size; still on the fence.

I thought Ross was talking about a 100 gallon tank. In size, they're much larger (both in height and diameter) than a 55 gallon drum.
Normally one of those 100 gallon tanks would set you back a grand or more. If Ross is looking at a functional 100 gallon tank for a hundred dollars, that's a steal.
 
There was a news clip a couple of years ago where an guy was halling one of those tanks in the back of his pickup when it fell over. He pulled into a Wal-Mart parking lot to take care of it and set off the propane that had collected in the box of his truck from static electricity which knocked him back 15 feet and ignited the stream of gas coming out of the leaking valve. That cut through the bed of his truck and into the gas tank which make one heck of a fire. That in turn heated what was left if the propane in the tank until it exploded and knocked a bunch of shelves over in the Wal-Mart from the concussion. It even caused light fixtures to fall in a building across the parking lot. Luckily everyone took off running when the gas tank lit off so no one was seriously hurt. I think the driver just ended up with burns on his face and possibly some dirty britches. Those thanks really do need to be carried in a vehicle safely. I lash mine to a seat in my van with I take them in for filling.

Doug
 
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