A burner, comprising: an oxygen supply tube and a burner tip defining a concave face; wherein the burner tip defines a main oxygen nozzle having a parabolic shape.

An organic colorant complex with the following general structure:

AB.sub.n(DE).sub.mT.sub.xQ.sub.y

wherein A is an organic chromophore; B is an electrophilic reactive group covalently bonded to A directly or through a linking group; D is a nucleophilic linking group covalently bonding B and E, selected from the group consisting of NR, O, S, and 4-oxyanilino (—HN-Ph-O—); wherein R is selected from the group consisting of H, alkyl, aryl, and E; E is an organic alkyl and aryl group or an end group; T is an ionic group covalently linked to A; Q is an organic cation, bonded to the organic chromophore A through ionic interaction with T; n, m, x, and y are independent integers from 1 to 10.

A method comprising applying braze to a joint location of two work pieces and applying local heating to the joint location of the two work pieces until braze melting temperature is achieved to melt the braze while maintaining temperature of more remote portions of each work piece. The method includes reducing heating of the braze to form a braze joint joining the joint location of the two work pieces.

A method comprising applying braze to a joint location of two work pieces and applying local heating to the joint location of the two work pieces until braze melting temperature is achieved to melt the braze while maintaining temperature of more remote portions of each work piece. The method includes reducing heating of the braze to form a braze joint joining the joint location of the two work pieces.

Provided is a gas furnace. The gas furnace includes: a manifold with an exhaust port for discharging fuel gas; a nozzle attached to the exhaust port; a burner for burning a mixture of air and fuel gas ejected from the nozzle; a primary heat exchanger that provides a first flow path and allows a combustion gas produced by the combustion of the mixture to move through the first flow path; and a secondary heat exchanger located adjacent to the primary heat exchanger, that provides a second flow path and allows the combustion gas discharged from the primary heat exchanger to move through the second flow path, wherein the secondary heat exchanger includes: at least one tube forming the second flow path; and a baffle inserted into the at least one tube, the baffle including: a plate longitudinally extending in a lengthwise direction and twisted in the shape of a screw; and a plurality of holes formed to penetrate the plate.

Provided is a gas furnace. The gas furnace includes: a manifold with an exhaust port for discharging fuel gas; a nozzle attached to the exhaust port; a burner for burning a mixture of air and fuel gas ejected from the nozzle; a primary heat exchanger that provides a first flow path and allows a combustion gas produced by the combustion of the mixture to move through the first flow path; and a secondary heat exchanger located adjacent to the primary heat exchanger, that provides a second flow path and allows the combustion gas discharged from the primary heat exchanger to move through the second flow path, wherein the secondary heat exchanger includes: at least one tube forming the second flow path; and a baffle inserted into the at least one tube, the baffle including: a plate longitudinally extending in a lengthwise direction and twisted in the shape of a screw; and a plurality of holes formed to penetrate the plate.

A gas burner for a household appliance includes a burner housing having a mixing chamber for mixing fuel gas with primary air, a gas nozzle accommodated in the burner housing and configured to inject the fuel gas into the mixing chamber, and an annular first primary air inlet provided between the gas nozzle and the mixing chamber for drawing in the primary air. The gas nozzle has a second primary air inlet which is guided through the nozzle for drawing in the primary air. The second primary air inlet is configured in a direction of flow of the primary air through the second primary air inlet to taper at least once and to widen out again. The gas nozzle has an annular fuel gas outlet opening which opens directly into the second primary air inlet.

Sparkless igniters comprising a hot surface igniter assembly and a nozzle that produce a flame plume with diameter substantially similar to the diameter of the fire tube, and flame length less than the length of each leg of the U-shaped fire tube in heater treaters are applicable to both vertical and horizontal heater treaters and improve the durability of fire tubes while reducing igniter fuel consumption by at least 30%.

Sparkless igniters comprising a hot surface igniter assembly and a nozzle that produce a flame plume with diameter substantially similar to the diameter of the fire tube, and flame length less than the length of each leg of the U-shaped fire tube in heater treaters are applicable to both vertical and horizontal heater treaters and improve the durability of fire tubes while reducing igniter fuel consumption by at least 30%.

Improvements for a gas burner bar are provided utilizing reduced parts, easier assembly, and greater reliability. In one or more implementations a portion of an air shutter is disposed between two parts of an injector assembly: an injector and an injector fitting. Assembly in this manner results in proper alignment of the injector assembly thus negating problems that arise with misalignment.