forced air burners

[Atlas Knife Company]

I seem to only see posts about fan powered burners. Could anyone using a compressor powered burner tell me how they like them?

 

[Daniel Rohde]

I have not heard of using a compressor for a burner but I would like to hear others comment to.

 

[Atlas Knife Company]

Really? The hassle of converting a blower instead of just hooking of the compressor makes it seem much easier. It should run on really low PSI, so the compressor wouldn't be running constantly.

 

[timgunn1962]

Compressors tend to be very inefficient at providing high volume, low pressure air. They are designed to do precisely the opposite: low volume, high pressure.

If you have a compressor, it can certainly be done, but the energy cost for the compression will be high and, as you can get similar performance from a good Venturi burner, probably not economically viable.

Looking at the one in the photo, it's not clear whether all the air is provided by the compressor, or if it is effectively a Naturally Aspirated burner with the compressor providing some extra air.

 

[Omega Leather Works]

Would a small continuous running (thinking air brush) compressor work?

 

[Stacy E. Apelt - Bladesmith]

Compressors are air supplies. If the supply is sufficient, and the pressure is regulated well...it will work... "Ah, but there is the rub".

The concerns Tim expressed are the main issues. Compressor regulators are made to work well at 50-100PSI, but run rather poorly at 5-10PSI. As the compressor cycles on and off, the low pressure output may vary...causing the burner to change its mix. This may make the burner run rich or lean variably. Evenness of air flow and proper volume is crucial in a blown system.

The burner would have to be a standard blown burner. The one shown is a venturi burner with a cap going to a compressor. This isn't really going to work right. At the minimum, it should have a larger volume manifold for the incoming air (12" of 1.5-2" pipe) and the fuel gas should come in unimpeded through a 1/4" side fitting. You do not need or want an orifice of any type in a blown burner. Fuel gas supply is completely different and at lower pressure.

For those with a large commercial shop and a big compressor, a secondary low pressure regulator that is designed to handle high volume would work...but the cost would be much more that just using a proper blower.

Final comment;
On many of the worst failures in making forges and melting blades, I have seen a compressor or a shop-vac as the air source.