Indugas, Inc.

Gas Research Institute

Midland-ross Corporation

Southern California Gas Company

Columbia Gas Service System Corporation

Ford Motor Company Limited

Hercules Corporation

Surface Combustion, Inc.

Klaus H Hemsath

Arvind C Thekdi

Frank J Vereecke

James E Lyon

Thomas J Schultz

Franklin G Rinker

H Kenneth Staffin

Rodney G Whitbeck

Dennis A Chojnacki

Mark G Shapona

Claude Melvin Mack

James G Conybear

Jay K Shah

Steven H Verhoff

Being-I Fu

Arvind Chhotalal Thekdi

Michael Owsiany

Ronald Scott Lucas

A thermal treating apparatus and process providing convection thermal transfer for elevated processing temperatures and chemical treatment. A recirculation plenum for passage of spent treatment fluid from and fresh treatment fluid to a treatment chamber may contain a thermal control source, a chemical control source, and a blower to provide predetermined programmable temperatures and chemical environments to articles in the treatment chamber. Decreasing cross sectional areas along the length of the treatment chamber cause introduction of fresh treatment fluid at different locations along the length of the treatment chamber to achieve desired uniform thermal and chemical treatment of articles along the length of the treatment chamber.

Thermal treating apparatus and process

An improved convector plate is provided for a batch coil annealing furnace. The plate includes a top annular plate, an identical bottom annular plate and an annular diverter plate in between. A plurality of slotted openings are provided in the top and bottom plates which extend radially outwardly from a first imaginary circle spaced from the inner peripheral edge of the top and bottom plates to an imaginary second circle spaced inwardly from the top and bottom plate's outer peripheral edge. The annular diverter plate is radially centered within the slotted openings. When the convector plate is placed between the edges of two coils, furnace atmosphere flows into the convector plate in the space between the top and bottom plates and is directed by the diverter plate into the slotted openings which are now covered by the coil edges thus establishing improved convective heat transfer rates with the coil edges resulting in shorter annealing process times.

Daisywheel convector plate for batch coil annealing furnace

A heat exchanger includes a long, thin-shelled heat transfer tube closed at one end and secured at the other end to a manifold collar which has an exhaust tube extending from the center thereof and a manifold housing extending from the collar side opposite that from which the heat transfer tube extends. A plurality of longitudinally extending distributor tubes extend from the heat transfer tube through the collar in fluid communication with a sealed manifold chamber and a plurality of orifices spaced at longitudinal increments along the length of each distributor tube permits the wind mass in the manifold chamber to exit the orifices as high speed, free-standing gas jets for impingement against the interior of the heat transfer tube so that the heat transfer tube acts either as a heat source or as a heat sink. An annular manifold plate spaced slightly from the collar defines a cooling space between the manifold plate and collar and orifices within the manifold plate permit a small portion of the wind mass to enter into the cooling space for heat transfer cooling of the collar while the collar also shields the manifold plate from heat within the heat transfer tube. A bleed path between exhaust tube and collar allows the gas in the cooling space to flow through the exhaust tube to maintain the manifold collar at an even temperature gradient.

High convective heat transfer immersion heater/cooler

A temperature probe is disclosed for determining the temperature at which residual oils can be vaporized from cold rolled strip without producing free carbon. The probe includes an open ended first tubular member with a burner mounted at one end of the first tubular member for closing the end thereof so that the burner fires its products of combustion through the first tubular member and out the other end thereof. A closed end second tubular member concentrically receives the first tubular member to define an annular heat space therebetween and has an exhaust port in fluid communication with said annular heat space adjacent the burner. Insulation extends on the inside of the outer tubular member for a fixed distance thereof from the exhaust port and a water jacket adjacent the exhaust port provides a temperature gradient along the length of the tube coincident with the insulation to provide a steady state, temperature indicating device in which the temperature varies, as a gradient, along the length of the outer tube.

Temperature probe for determining carbon sooting temperatures of oil

An improved seal arrangement is disclosed for use in batch coil annealing furnaces. The furnace has extending from its base a pair of cylindrical upright supports having exposed membrane engaging seal edges and between which an underpressure chamber is formed. The inner cover which removably rests on the base, has an annular top plate extending radially outwardly from its sidewall adjacent the cover's bottom end. Extending vertically downwardly from the top plate are concentric inner and outer clamp mechanisms which clamp flat annular elastomer seal therebetween. An overpressure chamber is formed between the seal and the top plate and when the inner cover is seated on the base, an underpressure chamber is formed between the seal and the upright supports. A positive pressure is applied to the overpressure chamber and a vacuum is drawn in the underpressure chamber to insure that the seal is forced into sealing contact with the upright engaging surfaces, thus assuring a positive seal of the inner cover with the furnace base.

Seal arrangement for batch coil annealing furnace

Method and apparatus is disclosed for heat treating coiled, metal strip in bell shaped annealing furnaces employing an annealing stand upon which coils of strip are vertically stacked. An inner cover removably sealed to the stand surrounds the coil and an outer cover surrounds the inner cover. A vacuum is drawn within the inner cover while the work is being preheated to volatize oil on the coil into hydrocarbon vapors and permit the hydrocarbons to be drawn off prior to annealing so that carbon soot formation does not occur. A unique concentric, two seal arrangement is disclosed which provides for drawing a vacuum between the seals to positively seal the inner cover to the base while providing a fail safe mechanism for monitoring the process thus permitting a potentially explosive reducing atmosphere, such as pure hydrogen, to be used in the annealing furnace in a safe manner.

Method and apparatus for batch coil annealing metal strip

An improved batch coil furnace is disclosed in that the annealing stand or base of the furnace is provided with a source for auxiliary heating or cooling of the work. A cylindrical containment wall is heated by hot burner products of combustion convectively impinging the outside surface of the containment wall. A unique jet tube impingement bundle is positioned within the base to form the recirculating cover atmosphere into jet streams which convectively impinge the inside surface of the containment wall. The furnace atmosphere is thus heated prior to being recirculated into the inner cover with the result that the temperatures of all the coils within the inner cover are more uniform. Provisions are made for cooling the outside surface of the containment wall after the coils have been heated to their transformation temperature. Finally, a baffle is applied to the base portion of the inner cover which, in conjunction with water cooling of the inner cover's annular flange, permits a constant temperature gradient to occur within the inner cover to avoid premature thermal fatigue or shock failure.

Batch coil annealing furnace

A high temperature, low NO.sub.x industrial furnace uses coal-fired burners placed in an arcuate heat track conduit which heats an arcuately configured wall member extending through an opening in the heat track conduit. The heated portion of the wall member rotates out of the heat track conduit to indirectly heat a bundle or bank of heat exchange tubes while an unheated wall portion moves into the opening vacated by the heated wall portion. The regenerative heated wall member thus permits the heat exchange tube bundle to be heated to high temperature without exposure to the burner products of combustion. The coal-fired burners are operated substoichiometrically to produce combustibles and a free-standing, jet entrainment arrangement is utilized to achieve staged combustion to avoid NO.sub.x formation.

High temperature furnace

An improved convective heat transfer arrangement is disclosed achieving overall heat transfer efficiencies in the neighborhood of 30 Btu/(hr. ft.sup.2 .degree.F.). A heat transfer conduit including a heat transfer wall is axially divided into a plurality of axially extending heat transfer chambers by a plurality of transversely extending baffles. Each baffle is especially configured to have an axially extending recess formed therein through which extends an orifice opening. Heat transfer gas pumped through the conduit cascades through the heat transfer chambers forming and reforming nascent free standing jet streams through each baffle orifice which impinge the heat transfer wall to achieve very high heat transfer coefficients while efficiently utilizing the available heat in the heat transfer gas.

Convective heat transfer by cascading jet impingement in a batch coil

An improved cooling cover is disclosed for use in bell shaped annealing furnaces. The cooling cover includes a jet nozzle orifice arrangement which develops jet streams from a low pressurized supply of air at ambient temperature in the plenum chamber of the cooling cover. A multitude of free standing jet streams thus impinge the inner cover of the bell shaped annealing stand to produce improved cooling times. Importantly, the plenum chamber includes strategically placed axial jet pump outlets which are effective to draw the jet streams from the cooling cover after they have been in heat transfer contact with the inner cover in a distribution pattern which is not altered so that the work or coils within the inner cover can be more uniformly cooled than heretofore possible. The spent jet streams are withdrawn from the cooling cover in a manner which does not affect the initial impact of the jets with the inner cover while establishing a neutral to slight under pressure at the base of the cooling cover to prevent sand seal upset and hot gas backwash.

Cooling cover for batch coil annealing furnace

Modifications are provided to a standard, batch type industrial heat treat furnace of a hot wall design which permit the furnace to be operated efficiently at high temperatures. The furnace is of a cylindrical design having a forward heat treat chamber and a rearward plenum chamber with a flat bulkhead plate in-between the chambers. The bulkhead has exit and inlet openings permitting wind mass to flow to the heat treat chamber and back to the plenum chamber. The bulkhead has a plurality of radially extending slits formed therein which permit the bulkhead to remain flat despite temperature and pressure gradients resulting in expansion/contraction of the bulkhead. Additionally, the furnace includes a closed end muffle within the heat treat chamber into which work to be heat treated is placed. A water cooled spring biasing support is provided for the closed end of the muffle to resist downward deformation of the muffle at high temperatures. The furnace additionally includes a heat shield circumscribing the furnace casing to provide a cooling air space for preheating burner combustion air while minimizing heat losses and the cost of furnace insulation.

High temperature industrial heat treat furnace

A simplified, low cost absorption heat pump includes a single pressure vessel having first and second insulated compartments in unrestricted fluid communication with one another and containing, hermetically sealed, a working medium. A heat transfer ar is used to maintain the compartments at differential temperatures, but equal pressures so that the absorption cycle proceeds in a two-stage, batch mode, namely boiling of the working medium in the first compartment and simultaneous condensing in the second compartment during the first stage and evaporating in the second compartment and simultaneous absorbing in the first compartment during the second stage. The heat transfer arrangement then utilizes the heat given off or taken in during the absorption cycle for heating/air conditioning in a conventional manner. Periodically the working medium is rectified by a unique pump arrangement which transfers any working medium in the second compartment back to the first compartment after a predetermined number of cycles have been completed.

Simplified, low cost absorption heat pump

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

An improved convective heat transfer arrangement is disclosed achieving overall heat transfer efficiencies in the neighborhood of 30 Btu/(hr. ft.sup.2 .degree. F.). A heat transfer conduit including a heat transfer wall is axially divided into a plurality of axially extending heat transfer chambers by a plurality of transversely extending baffles. Each baffle is especially configured to have an axially extending recess formed therein through which extends an orifice opening. Heat transfer gas pumped through the conduit cascades through the heat transfer chambers forming and reforming nascent free standing jet streams through each baffle orifice which impinge the heat transfer wall to achieve very high heat transfer coefficients while efficiently utilizing the available heat in the heat transfer gas.

Growing community of inventors

Toledo, OH, United States of America

Klaus H Hemsath