Midland-ross Corporation

Gas Research Institute

Southern California Gas Company

Arvind C Thekdi

Klaus H Hemsath

Frank J Vereecke

Richard R Mayers

Dennis A Chojnacki

Robert A Schmall

Timothy J Kuhn

James W Bender

Steven H Verhoff

James G Conybear

Robert W Buchwald

An industrial gas burner is disclosed which operates at low air/fuel ratios to avoid NO.sub.x formation without carbon sooting. The burner includes a refractory block having a cylindrically stepped throat passage extending therethrough, a housing adjacent the inlet end of the refractory block and a swirl plate inbetween the block and housing. Vane passages in the swirl plate provide fluid communication between the throat passage and an annular entrainment passage in the housing. A plurality of circumferentially spaced gas jet nozzles in the entrainment passage cause jet entrainment and mixing of fuel and combustion air which is ported to the entrainment chamber. The jet streams of mixed air/fuel impinge the swirl plate whereat the mixture undergoes a further mixing because of the pressure drop and swirling therein. The swirling air/fuel mixture is thus intimately and thoroughly mixed when it exits the swirl plate as a swirling mass at the entry end of the throat passage where it is ignited. The mixing is so intimate that combustion of the air/fuel can occur at ratios as low as 5 to 1 without carbon sooting and NO.sub.x formation.

Ultra low NO.sub.x industrial burner

A retractable, roller hearth for use in an industrial heat treat furnace is disclosed whereby the alloy rollers are retracted from their load bearing position when the furnace heat treat processes are underway thus maintaining the rated load capacity of the furnace. A plurality of guided rail support posts and guided, sealed lift posts accurately assure straight line vertical motion of the refractory base enabling contact between fibrous rope seals to seal the hearth from the cooler, lower portions of the furnace when the hearth is in a raised position.

High capacity, retractable furnace hearth

The present invention is a method and apparatus for heat treating at least one work item, such as a coil, having an axial passage and being axially stacked on a base support means disposed within a cover means which is located on the base support means. The base support can be on the floor of a furnace and with the chamber of the furnace. A means to force the atmosphere such as an axial fan is located in the base. The atmosphere is forced axially from the base, up through an axial path including the axial passage of the at least one coil, through a top space between the top of the stack of coils and the top of the cover means, down through the annular space between the outside of the coils and the inside of the cover means, and back to the axial path through a base space beneath the at least one coil, communicating from the annular space to the axial path.

Batch coil annealing furnace baseplate

The present invention is an improved apparatus and method for directly heat treating articles in a sealed treatment chamber of the heat treatment furnace. A burner means fires into a precombustion chamber which is connected in communication with the treatment chamber. Combustion is completed in the precombustion chamber and the products of combustion are fed into the treatment chamber. Additional treatment gas such as an endothermic gas is fed directly into the furnace treatment chamber.

Direct heating of heat treat furnace chamber

An improved container used in baking furnaces for baking carbon products. The container has a porous base and porous walls connected to the base. A porous medium is disposed between the container and the carbon product. Volatiles and liquid tars released during the baking of the carbon products pass through the porous medium and through the porous container.

Container for baking carbon products

A burner within which there is a jet pump means. High pressure primary combustion air is fed to an inlet in the burner housing and then through the jet pump means. The high pressure air flowing through the jet pump means draws a secondary low pressure, high temperature air into the burner. The jet pump means entrains the secondary air within the primary air to form a combustion air mixture. A fuel means feeds fuel to the burner housing and the combustion air and fuel combine to form a suitable mixture for ignition. A swirler can be located within the means to feed the primary air to the inlet or within the burner itself. By swirling the primary air the flame pattern of the burner can be controlled. The burner of the present invention is particularly adaptable for soaking pits having a tile recuperator and the metallic recuperator disposed within a flue gas passageway.

Burner for high temperature combustion air

A radiant burndown tube for furnaces which have a chamber sealable from the ambient atmosphere and in which there is a combustible gas. The burndown tube is divided into three functional areas; the burner leg, the exhaust leg and a tube portion. The tube portion is located within the furnace chamber. There is an inlet where the combustible gas from the furnace chamber is drawn into the burndown tube. The combustible gas is mixed with air and ignited in the tube and the combustion products are exhausted via the exhaust leg. Thus, the heat energy normally lost in the burndown of combustible furnace exhaust gases outside of the furnace is captured and used to provide additional heat to the furnace.

Furnace with radiant burndown tube

A device which is positionable within a flue for recapturing heat from hot gases exiting the flue. The device comprises a pair of tubes which are disposed in parallel relation longitudinally of the flue. The tubes are formed from cylindrical tubes which have been flattened from a circular to a generally oval cross-sectional configuration. A shield is positioned longitudinally between the two tubes for radiating against the tubes, heat which contacts the shield by convection.

Device for preheating air used in combustion

A high momentum industrial gas burner designed to create a high velocity which, in turn, is capable of creating high wind circulation that can be maintained during burner turndown. The various chambers of the burner are specially designed, so that fluid pressure within the burner is less than atmospheric pressure, or the fluid pressure within the heating chamber of a furnace wherein the burner is used to heat, for example, air.

High momentum burners

There is provided an efficient, economical apparatus for cooling hot gases which includes three generally cylindrical, tubular members arranged in an upstanding U-shaped configuration. The hot gases are introduced downwardly into the first leg or member of the configuration where a plurality of water nozzles provide a water boundary circumscribing the interior of the first leg to prevent thermal fatigue thereof. A water nozzle in the first member acting as a jet pump entrains the hot gases and directs them into the transverse leg or member of the configuration for rapid,turbulent cooling therein. Packed beds are provided in the second upstanding leg or member of the configuration to permit scrubbing of the cooled gases prior to exit. Coolng the gases in such a manner permits the entire configuration to be constructed of steel plate without any special insulation.

Apparatus for cooling hot gases

A gas burner is provided with a rich combustion chamber contiguous with a second combustion chamber through which combustion air enters in predetermined flow patterns to enable the burner to be self-stabilizing in a highly efficient manner. The rich combustion chamber receives air through a first port arrangement which, among other things, establishes underpressure zones at the center of the rich combustion chamber and air layer zones thereabout. Combustion air is supplied to the second chamber by a second port arrangement which, among other things, assures thorough combustion therein independent of the burner firing rate. When a longitudinal stream of gaseous fuel is exhausted into the rich combustion chamber, the underpressure zones force same outwardly to mix with combustion air in the first chamber while positive pressure in the second chamber is effective to recirculate a portion of the mixture whereby a sufficient combustion level is achieved in the rich combustion chamber to minimize carbon formation while the air layer zones resulting from the first port arrangement assure that carbon will neither be formed nor deposited therein.

Growing community of inventors

Sylvania, OH, United States of America

Arvind C Thekdi