Combustion furnace and burner

A combustion system for burning air and gas thereby creating a flue gas for heating a work piece rotated and passed through the combustion system, comprising:

• a hearth lined with refractory;
• an elongated combustion chamber formed in said refractory, said chamber having a flue gas exit into said hearth adjacent to which the work piece passes;
• an air manifold for receiving the air and mounted on said hearth with an insulator disposed therebetween;
• at least one gas manifold for receiving the gas;
• at least one aperture extending from said air manifold through said insulator and communicating with said combustion chamber, said gas manifold extending through said aperture to form an annular chamber for the passage of air from said air manifold to said combustion chamber;
• said gas manifold having aspirating means for combining the gas from said gas manifold with the air flowing through said annular chamber from said air manifold to create an air/gas mixture;
• and
• baffle means on said gas manifold for restricting flow of the air/gas mixture, said aspirating means being juxtaposed to said baffle means whereby the combustion of said air/gas mixture in said combustion chamber forms the flue gas which increases in velocity as the flue flows through said combustion chamber and exits onto the work piece to heat the work piece by forced convection.