Building a Foundry Furnace Blower

This is NOT a a step by step tutorial for building your blower, but to show you how I did it and what worked for me.

I started off with a blower motor that I bought from the internet.

I added a gate valve to regulate air flow into the burn chamber instead of just depending on the air shut off from the sides of the blower itself.

I plumbed in an electric shut off valve that flows only one way. As long as power runs to the blower, propane gas can flow through the pipes. This is an emergency shut off that works automatically. In the event you trip a breaker and power is lost to the furnace, the gas flow is automatically cut off to prevent gas pressure from building up.

A J box is mounted to the top of the blower to provide electricity to both the blower motor and the electric gas shut off valve.

A one way needle valve is added in the gas line to get the right mixture air and gas adjusted for the proper burn. Notice that I also added a manual gas shut off valve to the line so I could shut off the propane flow from the tank to have an extra safety feature.

This is how the setup looks like where the air from the blower meets the gas from the tank before it flows into the burner chamber. I want to make sure that I can get the air flow and mixture of gas to go into the Venturi as safely as possible and get the highest heat to melt the steel.

This is the burner set up with blower. I tried to keep as many bends as possible out of the gas stream as I can. I didn’t want the air to have to flow through too many bends and slow it down.

Gas tape is used on all the pipe threads to prevent any outside air leaks into the pipes, and no gas leaks out of the pipes. The system runs on 110 VAC power from the outlet.