How much propane do I need for a forge?
Depends on the size of the forge, how many burners and how big the burners are specifically, but, on average a 20lb bottle is good for about six hours.
100lb Propane Tanks: A 100lb pound tank is approximately 4-foot tall and 1.5-foot in diameter. These types of residential propane tanks will hold a little less than 25 gallons of propane when full and can be used for things such as home fireplaces, dryers and grills.
Put your 100 lb tank on a scale. Subtract the tare weight from the number on the weight scale to determine how much propane is left. For example, if tare weight is 10 lbs and your tank is weighing 65 lbs. You have 55 pounds of fuel left (65 – 10 = 55).
Some of the drawbacks to using gas is that it's noisier, and it makes the shop hotter in the summer time. Depending on the type of smithing that your doing gas is also generally considered more expensive than coal. The biggest drawback to most gas forges is the limited size of the forge itself.
Bituminous is the coal-of-choice for the blacksmith. It is a soft, mid-grade, black coal. Mined from deeper mines than lignite, it burns much more cleanly.
Never transport a 100-lb cylinder in a sedan or SUV or on its side. You may transport up to 1,000 lbs of propane in the back of an open pickup truck or trailer. However, our certified propane team can only fill 100-lb cylinders if they come in and leave in a secured and upright position.
A 100 lb. tank holds 23.6 gallons and weighs 170 lbs. when full. As mentioned, there are additional factors that can affect the overall amount of usable propane within the tank.
When a propane tank is filled properly, propane releases a quick spurt when the connection is released. Sometimes, too, no spurt will be heard. So, yes, a propane tank can be overfilled, which makes it important to know the risks and how to handle the situation.
The burners can run efficiently across a pressure range of 3- 20 PSI.
How much ventilation does a propane forge need?
The rule of thumb for the vent is at least seven times the cross sectional area of the burner.
The real challenge is getting fresh (oxygen rich) air into your shop against this positive pressure. If you don't ventilate enough, you end up running your forge in an oxygen deprived environment and then you risk carbon monoxide poisoning (due to incomplete combustion).
A: From my experience in the industry, we generally used the "13 -16 minutes per inch" guide for forging temps for alloy steels in large rotary or pusher furnaces.