Empire force air forge

[Cleat]

Hello All, I just picked up an Empire forge made in Los Angeles I don't know anything about this type of burner. I work with silicone bronze for boat hardware and just kind of dropped into my lap for cheap $. I plugged it in and tried the blower and it worked smoothly with the variable speed knob.

I don't know how much propane it will require as far as cubic meters per hour and I don't know how to light it. The only regulators that I have found here in Mexico run around 1 cubic meters/hour no different than a BBQ or turkey fryer.

I don't know how to light it and I want to any help would be appreciated

Thank you,

George 

[Mikey98118]

1 hour ago, Cleat said:

The only regulators that I have found here in Mexico run around 1 cubic meters/hour no different than a BBQ or turkey fryer.

Than you will have to buy a variable pressure regulator from somewhere else, since that is about five percent of what you'll need.

[George N. M.]

Welcome aboard, George, from another George at 7500' in SE Wyoming.  Glad to have you.

Once you have the regulator set up and a proper flow of gas, the way I light my forge (modified Sandia with doors) is to wad up a piece of newspaper, put it in the forge, light it, and then turn on the gas.  It usually lights with a soft "whomp."

I suggest that you put your location in your profile.  We will forget that you are in Mexico pretty quickly.

"By hammer and hand all arts do stand."

[Irondragon Forge ClayWorks]

Welcome from the Ozark mountains. With the gas pressure stated between 6-8 IN"H2o indicates to me it is designed to operate on natural gas, not propane. Natural gas pressure of 7IN" H2o here in the states is about 1/4 psi. If you want to operate it with propane the jet(s) in the burner(s) would need to be changed to propane jets. You might check with a propane supplier to see if they have any information about it.

This article by Marc Ward in Clay Times explains all that.

Gas Pressure

by Marc Ward Clay Times Aug. 1997       "If there is any one single item, besides BTU's, that remains a mystery to potters, it is gas pressure. Most folks use pressure gauges on their burners, so they have some idea of the pressure they are using. I say "some" idea because gauges sometimes don't give you an accurate reading. This is especially true in low pressure situations.     What's low pressure? Low pressure is any pressure below 1 pound per square inch (PSI). When dealing with pressures below 1 PSI, you will see the term "inches" or "inches of water column".  This refers to the amount of pressure it takes to raise a column of water 1 inch. There are 27.7 inches of water column (wc) pressure in 1 PSI of pressure.  So 7"wc is about 1/4 PSI. This is the normal pressure that household natural gas is delivered. The normal delivery on propane (LP), for household use is 11"wc or a little more than 1/3 PSI.     Both of these pressures are the result of the regulators on the gas line. In the case of natural gas, the meter acts as a measure of volume (so you can get a bill) and as a regulator. In many situations, you'll have 25-35 PSI of natural gas coming into the meter. The meter reduces this pressure to 5-8" wc. In some industrial settings, you may be able to receive greater natural gas pressures. In a non-industrial setting, I wouldn't count on higher pressures. Propane tanks also use regulators. A full propane tank in the summer sun, may have 250 PSI worth of pressure. This is regulated down to the 11" wc, as mentioned before, or can be delivered at higher pressures with the appropriate regulator. Because the tank pressure will change with temperature and the volume of fuel it contains, you should always have a regulator on the tank. This holds true whether the tank is a small "Bar-B-Que" tank or a 1000 gallon tank the size of a small sub. Since you are not connecting to a public utility, as with natural gas, there is more leeway as to what you can do with your gas supply. Because of this, propane offers more options as far as pressure delivery. But, propane is more expensive. Currently, BTU for BTU, propane is more than twice as costly as natural gas.   Propane contains 2500 BTU's per cubic foot vs. 1000 BTU's per cubic foot for natural gas. Even though natural gas is far less expensive, it can have some disadvantages. I get to "break the news" to folks about this on a regular basis. They buy a used kiln that had been fired on propane and they now want to convert it to natural gas. That's fine, but they may not be able to use the same burner system. If that kiln had four burners that had been fired on propane at 10 PSI, they're in trouble. They want to switch from a fuel that had 250% more BTU value and was delivered at 4000% more pressure. You can see they are going to come up short with natural gas using the same four burners. No amount of drilling out orifices is going to help this situation. This isn't to say that natural gas is a bad choice. It's cost and ease of delivery, actually make it the fuel of choice. You'll just need to be aware of it's limitations if you are used to propane.   The regulated pressure on the line is referred to the "manifold pressure". This is not the pressure that your gauge may read, but the pressure that the meter or regulator is set for. Know your manifold pressure. This pressure, along with the orifice size, determines the BTU output of your burners. If you're unsure of the pressure, contact you natural gas utility or your propane supplier."

I can't control the wind, all I can do is adjust my sails. ~ Semper Paratus

[Latticino]

Light industrial furnaces like this one also have integral safety systems in the gas train.  From the photo I see what appears to be a safety solenoid valve as well as a final internal regulator.  Both will have to be functioning properly to use your forge.  Note that he regulator may be setup like mine as a zero pressure regulator that varies the flow of gas in parallel to the air flow.  If so you may have an adjustable orifice as well, which will set the relative proportion between the two.  You still would likely have to change out the orifice if you switch from natural gas to propane.  If you do have natural gas available it will be more convienient.

When lighting a forced air gas forge it is critical to turn the air on first.  Then deal with your ignition source (wadded newspaper or hand held propane torch) and only turn the gas valve on after the forge door is open and the ignition source is lit near the burner.  As George mentioned, you may get a bit of a blast when it first lights.  You will need to learn what air and gas settings are best for the initial firing.  Shutting down is the opposite sequence (gas off first, then air after a few minutes to keep the burner cool.

Note that these old furnaces were not really optimized for hobby work.  They typically have a lot of thermal mass and due to that take a long time to get up to heat (but hold their heat well during operations that open and close the doors regularly).  The other issue you may have is the operating range for the furnace.  Unless you get a manual somewhere there is no easy way to tell what it will tolerate.  The insulation may not be rated for forging temperatures.

[Frosty]

It should have a badge with the maker's name, model and serial and patent number. Most industrial furnace companies have manuals, parts lists and a phone # to call for help.

The information in your post isn't complete enough for me to find that furnace or the company online.

Frosty The Lucky.

[Cleat]

Thank you everyone! Way more information and replies than I expected!

[Frosty]

You're welcome Cleat, sharing info and helping each other is why most of us old timers are here.

Frosty The Lucky.