Abstract: Cermic materials (i.e. architectural face-bricks) are fired in a tunnel kiln of the type having a firing zone and a downstream cooling zone. The cooling zone is segregated into indirect and direct cooling zones via a sealed gate structure therebetween. The heated gases in the indirect cooling zone are thus preliminarily cooled by suitable means (for example, a heat exchanger) and the cooled gases are returned via a closed-loop path to the indirect cooling zone. The fired ceramic materials in the direct cooling zone are finally cooled by the direct introduction of an oxygen-rich gas (i.e. ambient air). In such a manner, a reducing atmosphere may be maintained in the firing zone and in the indirect cooling zone while final cooling of the bricks occurs in the direct cooling zone. Thus, the oxygen-rich atmosphere of the direct cooling zone is prevented from entering the indirect cooling zone via the sealed gate structure thereby permitting frost-resistant bricks to be fired and cooled on a continual basis.

Abstract: Drying and baking installation in which the products pass through the drying oven (S) and the baking oven (C) on the same carriages (1) by means of a single, continuous path, without intermediate handling; the products are stacked without contact with one another by means of superposed ceramic supports; the outlet from the drying oven is connected to the entrance to the baking oven by an air-tight enclosure, the system thus forming a continuous and tight enclosure and the pressure of the gases as the products enter the baking oven is at least equal to the pressure of the gases as the products leave the drying furnace.

Abstract: A muffle furnace burnout section includes dual parallel spargers each having parallel first and second sparger sections. The region between the first and second sparger sections includes a thermal and gas barrier transition section secured to the spargers. The transition section is removable from the muffle with the sparger assembly as an integral unit. The transition section is adjustable and mates with a transition barrier plate secured within the muffle at the transition region.

Abstract: An ingot pusher furnace of the vertical air flow type includes distributing means for preventing short circuiting of a gaseous medium around the ends of ingots to be heated so as to produce a more uniform heat transfer along the entire length of the ingots. The distributing means comprises a pair of air distribution baffles which force the gaseous medium contained in an enclosure to flow towards the center portions of the ingots so as to facilitate uniform heating throughout the ingots. In an alternate embodiment, the distributing means comprises a pair of movable side baffles which is movable to an angled position so that its lower ends are adjacent the ends of the ingots.

Abstract: An apparatus for contacting solids with gases, preferably a needle coke preheater, which includes an elongated housing having an entrance and an exit and means for introducing solids into the entrance of the housing. A bed support divides the housing into an upper chamber and a lower chamber and is declined from the horizontal at an angle such that the solids introduced into the entrance of the housing slide down the bed support toward the exit of the housing. The bed support contains a plurality of openings distributed between two solid rectangular borders which serve as the two long parallel sides of the bed support. The openings are sufficiently large so that gases can flow from the lower chamber in contact with the solids and then into the upper chamber. The solid rectangular borders prevent preferential flow of the gases up the walls of the housing by forcing the gases to flow toward the center of the bed support.

Abstract: A rethermalization oven for heating food is disclosed, characterized by uniform distribution of heat and air through a heating chamber. The oven includes a housing and partitions for defining an outer U-shaped air plenum, a rectangular heating chamber, and a burner chamber. The side panels of the partition contain a plurality of spaced horizontal slots and the rear panel of the partition contains a plurality of spaced openings and horizontal slots of progressively increasing thickness in the directions toward the top and bottom of the housing. A heating element is arranged in the burner chamber for heating the air arranged therein.

Abstract: A high-temperature, rapid-cycle pin oven for the curing of coatings on hollow container components, includes an oven unit (2) whose housing (14) is divided into three compartments interconnected by internal explosion relief panels (136,142,144). One of the compartments (36), designed for a normal working pressure in the range 1 to 1.01 atmosphere, has a light explosion-relief panel (132) which provides primary pressure relief to atmosphere while ensuring that if the internal panels blow out, the entire interior is vented to atmosphere. This panel comprises a light casing (202) with thin tinplate bursting diaphragms (210) in the bottom, overlaid by a light, absorbent mattress (220), and a light top cover (222) which can blow out. A perforated hot air delivery screen (38) forms one wall of the narrow working chamber (34) and comprises a number of plates removably and replaceably fastened to a frame (72) fixed in the housing.

Abstract: The present invention provides a high efficiency, non-polluting curing oven, having an internal curing chamber comprising forward and rearward regions, bottom located forward and rearward access openings to and from the forward and rearward regions, a plurality of trays for carrying material to be cured through the curing chamber, a conveyor for conveying the trays to and from the forward and rearward regions through the forward and rearward access openings, a tray moving system for lifting the trays upwardly through the forward region and for transferring the trays to and for lowering the trays downwardly through the rearward region, a burner providing heated gases in a combustion chamber above the curing chamber and a fan for blowing the heated gases downwardly into the curing chamber for curing of the material with the heated gases rising back upwardly, creating a negative pressure to draw a supply of fresh outside air into the curing chamber, through the bottom located access openings.

Abstract: An ingot pusher furnace of the vertical air flow type includes distributing means for preventing short circuiting of a gaseous medium around the ends of ingots to be heated so as to produce a more uniform heat transfer along the entire length of the ingots. The distributing means comprises a pair of air distribution baffles which force the gaseous medium contained in an enclosure to flow towards the center portions of the ingots so as to facilitate uniform heating throughout the ingots. In an alternate embodiment, the distributing means comprises a pair of movable side baffles which is movable to be angled position so that its lower ends are adjacent the ends of the ingots.

Abstract: A high-temperature, rapid-cycle pin oven for the curing of coatings on hollow container components, includes an oven unit (2) whose housing (14) is divided into three compartments interconnected by internal explosion relief panels (136,142,144). One of the compartments (36), designed for a normal working pressure in the range 1 to 1.01 atmosphere, has a light explosion-relief panel (132) which provides primary pressure relief to atmosphere while ensuring that if the internal panels blow out, the entire interior is vented to atmosphere. This panel comprises a light casing (202) with thin tinplate bursting diaphragms (210) in the bottom, overlaid by a light, absorbent mattress (220), and a light top cover (222) which can blow out. A perforated hot air delivery screen (38) forms one wall of the narrow working chamber (34) and comprises a number of plates removably and replaceably fastened to a frame (72) fixed in the housing.

Abstract: A rotating shelf barbecue oven for commercial establishments is shown. Meats being barbecued are located on shelves in an upper compartment while heat and smoke for barbecuing comes from a lower compartment. Flues in the side walls provide for flow of heat and smoke from the lower compartment to the upper compartments. A shaft extends through the upper and lower compartments and connects to the shelves for rotating the shelves and meats thereon during barbecuing. The compartments, including the flues and the shaft, are constructed to allow for steam cleaning of the upper compartment without the water getting into the lower compartment. Also cooking grease is prevented from dripping into the lower compartment.

Abstract: The process of operating a reheating furnace for slabs involves the transport of slabs through the heating chamber of the furnace and contacting the slabs with a hot gaseous fluid which is supplied by one or more channels at a level below the path for the slabs. The fluid is thereby cooled and the cooled fluid is withdrawn to be readmitted into the channels subsequent to mixing with hot combustion products which are furnished by burners. The temperature of the fluid which is a mixture of cooled fluid and combustion products matches or approximates the optimum temperature for rolling of the slabs. That portion of the heating chamber which is adjacent to its inlet constitutes a magazine for temporary storage of slabs and contains ways for a charging machine which delivers slabs into the range of a walking-beam conveyor in the heating chamber.

Abstract: A continuous heat treating furnace for heat treating a ferrous metal work in a protective atmosphere, including a furnace separated into a charge chamber and a heat treating chamber by a partition door and provided with a transport device for transporting the work. A first heating device, a recirculating fan and a gas purge device are provided in the charge chamber, while a second heating device is provided in the heat treating chamber supplied with the protective atmosphere, whereby the work is preheated through convectional heat transfer in the charge chamber simultaneously with high-temperature purging of the charge chamber and then, is heat treated under the protective atmosphere in the heat treating chamber.

Abstract: Disclosed is a furnace having a furnace chamber formed with a work inlet and a work outlet, and a work mount turntable rotatably provided within the furnace chamber, the furnace further comprising work carry-in means for carrying a work while mounting the work thereon into the furnace chamber through work inlet to transfer the work onto given one of work mount portions on the turntable, and work carry-out means for carrying a work mounted on one of the the work mounts out of the work outlet while mounting the work thereon. Each of the work mounts, the work carry-in means, and the work carry-out means is constituted by a plurality of strip members disposed at regular intervals. The respective strip members of each of the work carry-in means and the work carry-out means are arranged to move up and down passing through the gaps formed between the adjacent strip members of the work mounts.

Abstract: An ingot furnace pusher furnace includes a fixed baffle assembly suspended from a furnace top wall. The baffle assembly includes a horizontal top baffle plate and a bottom baffle sheet disposed below the top plate. The bottom baffle sheet consist of a center portion and a pair of first and second upwardly sloping end portions connected to the center portion. The center portion is positioned substantially parallel to an upper suface of a center portion of the ingot. A first deflection baffle is rotatably supported at its one end by a pipe to the baffle assembly adjacent the first sloping end portion. A second deflection baffle is rotatably supported at its one end by a pipe to the baffle assembly adjacent the second sloping end portion. Linkage devices are connected to the other ends of the first and second deflection baffles for moving the same between a horizontal position parallel to the upper surface of the ingot and an acute angle position relative to the horizontal position.

Abstract: A tunnel dryer and method for drying unfired bricks or similar objects in which the tunnel comprises exhaust means for exhausting heated gases within the tunnel, partition means disposed in the drying space of the tunnel consisting of at least one vertically adjustable partition positioned upstream of the exhaust means, and means for positioning the vertically adjustable partition at an intermediate level within the drying space of the tunnel to define an effective drying zone for the unfired bricks.

Abstract: A continuous heat treating furnace in which independent sectioned chambers are provided at least in part of a pre-heating/pre-cooling zone in the furnace body, with a cooler or heater being provided in suction ducts of the sectioned chambers so as to rapidly heat or cool the metallic strip through operation of dampers disposed in the suction ducts, thus making it possible to alter heat curves as required for heat treatment of various metallic strips.

Abstract: A system for recovering resources from sludge in which sludge containing water in the amount of 90 to 70 percent is first supplied to a sludge concentrator through a forced supply equipment where the sludge is concentrated to contain a water content of a maximum of about 60 percent; then is sent to a drying furnace having a fluidized sand bed. The product obtained in the drying furnace is separated to gas and solid. After the separated gas is pressurized by a fan and is heated by a heat exchanger through a circulator passage, a portion thereof is supplied to the drying furnace as gas for drying and the remainder is sent to the sludge concentrator. The water content is then removed from the concentrated gas and the gas obtained from the sludge concentrator is used in the system as gaseous fuel.

Abstract: An ingot pusher furnace includes a horizontal baffle assembly suspended from a frame member located above a furnace top wall. The baffle assembly includes of a center portion and a pair of first and second upwardly sloping end portions connected to the center portion. The center portion is positioned substantially parallel to an upper surface of a center portion of the ingot. A first upper horizontal baffle is connected by a first gusset to the first sloping end portion. The first upper baffle is positioned substantially parallel to and above a first end portion of the ingot. A second upper horizontal baffle is connected by a second gusset to the second sloping end portion. The second upper baffle is positioned substantially parallel to and above a second end portion of the ingot.

Abstract: A tunnel oven 20 has a baking chamber divided by partitions 21 into a plurality of longitudinally extending zones 22. The oven heating system comprises upper and lower heater ducts 6a, 6b through which hot gases are passed, using a blower 24 for each zone 22. The intake of each blower 24 is within the associated zone 22 and is disposed adjacent the outlet end of an inlet duct 11 which leads into the lower part of the zone. An outlet 8 leads out of the upper part of each zone 22. The entry end 27 of the inlet duct 11 is open to atmosphere whereby fresh air is introduced into the duct. The exit end of the outlet duct 8 is connected to an exhaust fan 7 whereby gases are extracted from the zone 22 by way of the outlet duct 8 to an exhaust flue 18. Dampers 12 and 10 comprise first and second regulating means for controlling flow through the inlet and outlet ducts 11 and 8.

Abstract: This invention relates to a muffle furnace, for continuous heat treatment during passage of material therethrough, of products, the production cycle of which includes a treatment of predetermined duration at a temperature which may be about 1100.degree. to about 1150.degree. C., which furnace is heated by a flame producing burner without the combustion gases directly contacting the products to be treated. This furnace comprises: an inlet zone provided with a means for preheating, by circulating recycled combustion gases in a double casing provided around the muffle; a heating zone, provided inside a heat-insulated chamber provided with at least one means for circulating combustion gases around the heating zone of the muffle; and an outlet zone provided with at least one means for controlling the cooling rate of the treated product.

Abstract: A walking-beam furnace in the heating of metal bodies without bending in which at least a pair of walking beams straddle a stationary beam whose width is greater than that of the walking beams. The stationary beam is formed with a plurality of rectangular recesses opening at a support surface of the stationary beam upon which the metal bodies come to rest and communicate from below with a source of combustion gases so that the hot gas rises to contact the bottom of the metal bodies and the bottom of the metal bodies is subject to heating by radiation from the walls of the recess which converges downwardly to a duct supplying the hot gas. The width of the recess is greater than the widths of the portions of the fixed beam laterally flanking, while the length of the recesses is greater than its width.

Abstract: An oven and method for cooking food products. The oven comprises an elongated housing having an inlet for food products to be cooked in the oven and an outlet for emitting cooked food product from the oven, together with means for heating a gaseous cooking medium in the housing for cooking the food products therein, and a plurality of vertically tiered endless conveyors for passing the food product back and forth through the housing during the cooking process, whereby an oven taking less floor space for a predetermined flow path extent of cooking various food products, is provided.

Abstract: An improved ingot pusher furnace having a base carrying a plurality of laterally slidable shoes with upper surfaces smoothly tapering into said base. A pair of side walls is connected to said base with a top wall connected to said side walls to define a heating enclosure. A pair of end walls are connected to the base, side walls and top walls, each of the end walls having a vestibule, including a pair of double doors therein. A baffle assembly is movably connected to the top wall to be held in spaced proximity from an ingot to be heated.

Abstract: A roller conveyor furnace (12) is disclosed as including at least one gas jet pump (24) for providing forced convection heating of glass sheets during conveyance on rolls (22) of the furnace conveyor (20). A source (26) of compressed gas located externally of the furnace is communicated with the gas jet pump to supply a primary gas flow thereto and induce an amplified extent of a secondary gas flow in order to provide a combined flow of heated gas that produces the forced convection heating. Upper and lower arrays (70,72) of the gas jet pumps are disclosed as being usable separately or in cooperation with each other in one embodiment to maintain temperature uniformity and glass shet planarity. Each array includes an associated conduit support (74,76) that mounts the gas jet pumps thereof in a spaced relationship transverse to the direction of conveyance either above or below the conveyor rolls.

Abstract: An infrared furnace has a housing with insulated walls defining an elongated straight tunnel disposed on a longitudinal axis between an entrance and an exit. A conveyor continuously moves through the tunnel along the longitudinal axis between the entrance and the exit. A first plurality of elongated tubular infrared heating elements are disposed in the tunnel above the conveyor in spaced apart parallel relationship transverse to the longitudinal axis. A second plurality of tubular elongated infrared heating elements are disposed in the tunnel below the conveyor in spaced apart parallel relationship transverse to the longitudinal axis. The housing has insulated walls each comprising a porous insulative inner panel and a non-porous outer panel. At least one of the outer panels is spaced from its associated inner panel to form a plenum chamber therebetween. The insulated walls define an elongated tunnel in which a source of infrared radiation is disposed.

Abstract: A fiber treatment oven is disclosed in which hot gas is flowed parallel to and between fiber pathways within the oven to reduce deflection and breakage of fibers and to reduce end-to-end temperature variations in the oven. Hot gas is emitted centrally of the oven and flows toward ends of the oven. Preferably, an additional, generally tubular stream of hot gas is emitted centrally of the oven and generally surrounds and envelopes the fiber pathways to reduce side-to-side temperature variations.

Abstract: A roller conveyor furnace (12) is disclosed as including at least one gas jet pump (24) for providing forced convection heating of glass sheets during conveyance on rolls (22) of the furnace conveyor (20). A source (26) of compressed gas located externally of the furnace is communicated with the gas jet pump to supply a primary gas flow thereto and induce an amplified extent of a secondary gas flow in order to provide a combined flow of heated gas that produces the forced convection heating. Upper and lower arrays (70,72) of the gas jet pumps are disclosed as being usable separately or in cooperation with each other in one embodiment to maintain temperature uniformity and glass sheet planarity. Each array includes an associated conduit support (74,76) that mounts the gas jet pumps thereof in a spaced relationship transverse to the direction of conveyance either above or below the conveyor rolls.

Abstract: A paint bake oven (10) including an outer insulated housing (12), the outer insulated housing having an inner wall surface (14). An inner housing (16) is disposed within the outer housing (12) and has an outer wall surface (18) spaced from the inner wall surface (14) to define a gas flow channel (20) therebetween. The inner housing (16) has an inner product passageway (22). A gas supply plenum (46) is disposed above the inner housings for supplying a gas flow to the gas flow channel (20). A gas exhaust passageway (38) exhausts gas from the product passageway (22). The oven (10) is characterized by including a manifold wall (28) for directing the gas flow along a flow path from the gas supply plenum (46) downwardly along the inner wall surface (20) of the outer housing (12) and then upwardly over the outer surface (18) of the inner housing (16) to uniformly distribute the gas flow over the inner housing (16).

Abstract: Apparatus for imparting thermal energy to or removing thermal energy from a food product, said apparatus comprising intensive and semi-intensive thermal treatment sections and at least one equilibrating section.

Abstract: A furnace for heating pipes each having an upset portion at least at one of its opposite ends includes a housing defining a heating chamber filled with high temperature gas, and a conveying apparatus for sequentially conveying the pipes in the housing in a direction perpendicular to an axial direction of the pipes. A blowing device is provided on one side of a path of the upset portion, and a waving plate is provided on the other side of the path, whereby the upset portion, when passing through a space between the blowing device and the plate, is heated locally by the high temperature gas blown out from the blowing device and also by the reflected high temperature gas and radiant heat from the plate.

Abstract: Apparatus adapted to deliver a temperature-controlled gas from a common plenum to at least two thermal treatment zones is provided. The subject apparatus is adapted to direct columnated jets of a temperature-controlled gas so as to impinge on at least one surface of food products passing through such zones, and is further adapted to convey food products through such zones in multiple passes in which the food products are subjected to different thermal energy transfer rates in at least two of such zones.

Abstract: A large scale, industrial system and method for dehydrating fruits, nuts or other produce. The system includes two long air tunnels which are placed end-to-end. Each air tunnel has a conveyor which is used to transport the produce through the air tunnel. As the produce exits one air tunnel, it is dropped from one conveyor onto the other, thus permitting the produce to be turned over before it enters the second air tunnel. Each air tunnel is divided into a number of separate air chambers in which the heated, circulating air is confined so as to reduce heat loss, thus increasing the energy efficiency of the system, and also providing for separate control of the air temperature and humidity levels in each air chamber. Countercirculation of air between adjacent air chambers aids in confining the air through the separate air chambers, as well as the use of resilient flaps which are used to enclose the ends of each air chamber through which the conveyor enters and exits.

Abstract: A metal heating furnace for heating slabs, billets or blooms prior to their hot rolling. Full use to thermal energy can be ensured and the workpieces can be uniformly heated to a desired rolling temperature.

Abstract: In a kiln for firing ceramic workpieces, which kiln is composed of two opposed side walls and a top wall enclosing an elongate kiln chamber, and elements for introducing jets of heating or cooling gases into the kiln chamber at locations spaced along the length of the kiln, the elements are located for directing the jets produced thereby vertically in the region of the side walls of the kiln, and deflector stones are disposed at a distance from the elements for deflecting the jets and gases within the chamber transversely of the length of the kiln.

Abstract: Roller grate method and apparatus for simultaneously transporting, agitating and exchanging heat with a bed of solid mineral particles has elongated cylindrical horizontal rollers with gas passage apertures therethrough, a hopper for feeding mineral particles onto the rollers and forming a bed having a depth several times greater than the average diameter of the particles; a drive source to rotate the rollers and frictionally engage the cylindrical surfaces with the particles in the lowermost layer of the bed and urge the bed along a path of travel transverse to the axes of the rollers; elongated filler members disposed in the nip between adjacent rollers to prevent the particles from jamming the rollers and to provide resistance to the flow of the bed along said path of travel; and a heat chamber spanning the rollers and a fan for forcing a heat transfer gas stream through the gas passage apertures in the rollers and through the bed as it is being transported, the rollers and the filler members being adapted

Abstract: In the manufacture of clay or refractory ware containing oxidizable material, stacks of the ware are passed through a tunnel kiln and a flow of air passed over the stacks. Fuel burners are operated to provide the necessary stages for firing the ware. These stages include an oxidation stage in which residual oxidizable material is oxidized. Gas containing more oxygen than air (i.e. commercially pure oxygen or oxygen-enriched air) is introduced into the region of the kiln where the oxidation takes place. The oxygen-rich gas is caused to penetrate at least one stack for the time being in the oxidation region so as to increase the concentration of oxygen throughout the individual items of ware within said stack. It is thus possible to oxidize all the residual oxidizable material. At least 50% of such oxidation is typically confined to a temperature range of 100.degree. C. The heat thereby released assists in the firing of the ware.

Abstract: Flat articles, in particular printed circuit boards, coated with a curable material, repose at their edges upon two belt conveyors which are positioned at an inclination. By means of these belt or band conveyors, the printed circuit boards are fed, in a predetermined conveying direction, below a heating device containing at least one hot air infeed device. The surface or face of the printed circuit board confronting such hot air infeed device is therefore subjected to the action of the hot or heated air, resulting in curing or hardening of the applied material layer. At the opposite side of the printed circuit board, facing away from the hot air infeed device, there is arranged a collecting tube or pipe which extends in the conveying direction. This collecting tube is provided with outlet openings for cooling air. Hence, the lower face of the printed circuit board has applied thereto the cooling air.

Abstract: An industrial furnace, particularly a single-chamber vacuum furnace, for heat treatment of metallic workpieces, with a heating chamber which is formed in a housing, which heating chamber is heatable via heating elements and is provided on the bottom and on the ceiling with a closable chamber opening for the passage of a quenching gas which can be circulated by means of a blower. A flap is swingably mounted at the chamber opening underneath a closing slide, which chamber opening is provided for the entrance of the gas. The flap controls the incoming flow of gas within the range of the free cross-section of the chamber opening.

Abstract: Roller grate apparatus for simultaneously transporting and transferring heat to or from a bed of material particles has elongated cylindrical parallel horizontal rollers rotatably driven in the same direction; filler bars disposed in the nip between adjacent rollers and together with the rollers forming a generally flat surface with constantly moving portions which continually tumble the material particles and urge them thereacross in a direction transverse to the roller axes; gas passage apertures in the rollers which permit a heat transfer gas stream to pass through the rollers; a heat transfer chamber spanning the rollers; and a fan for blowing a heat transfer gas stream through the chamber and the material bed being transported by the rollers.

Abstract: Roller grate material bed conveying and heat transfer apparatus which provides plural bed depths has cylindrical horizontal rollers driven in the same direction with gas passage apertures in the rollers and filler members in the nip between adjacent rollers. Means are provided to pass heat transfer gas streams through the bed as the rollers urge the material particles in a direction transverse to the roller axes and continually tumble the particles so that all surfaces thereof are exposed to the gas streams. A first plurality of rollers are positioned in a first generally horizontal plane to receive the material fed to the apparatus, and a second plurality of rollers downstream from the first rollers are at elevations lower than the first horizontal plane and preferably are driven at slower speed than the first rollers to thereby increase the material bed depth downstream from the first horizontal plane as the material particles are hardened by heat and can withstand greater bed depth without crushing.

Abstract: An apparatus is disclosed for processing products aligned on a tape. In the present embodiment, the products are shown to be heat recoverable sleeves which are conveyed to a control station for insertion of a terminal. The work is then released from the control station and allowed to pass across a heater which recovers the sleeve about the terminal. To accomplish the above, a drive having a friction coupling and a positive coupling are employed to convey the work through the apparatus. A conditioned atmosphere process apparatus is employed for the heating of the sleeves and a controlled product feed apparatus controls the feeding of the work to the control station.

Abstract: A tunnel oven of elongated configuration and having at least one movable carriage therein for transporting ceramic products to be baked through the tunnel, is provided with a reversible blower operative to generate a stream of gas having reciprocating movement which passes through the tunnel in a direction opposite to the direction of movement of the carriage. The opposing sides of the tunnel are provided with inwardly extending projections and intervening recesses which give the overall tunnel a zig-zag or wave configuration; and fire stations are located adjacent the various projections or recesses for heating the reciprocating stream of gas and for producing cross currents which cause the stream to flow along a generally sinuous path through the tunnel in a flow direction opposite to the direction of movement of the carriage.

Abstract: A system for heating a furnace having a heating chamber defined by furnace walls is provided with a plurality of individual burner assemblies mounted on a furnace wall to direct heating gas streams into the heating chamber, each of the burner assemblies including a diffusion chamber, a burner arranged to direct products of combustion through the diffusion chamber into a furnace heating chamber and means for directing the flow of diffusion gases into the diffusion chamber to admix with the burner products of combustion so that the gas stream entering the furnace heating chamber has a greater mass velocity than the burner products of combustion, there being provided a diffusion gas supply means connected to the heating chamber of the furnace for delivering hot gases from the furnace heating chamber to the diffusion chambers of each of the burner assemblies.

Abstract: Agglomerates are fired in a sintering apparatus of the type, in which the agglomerates during transport on a travelling grate in zones along said grate are pre-dried with substantially pure warm air passing upwardly through the grate and finally dried and heated with hot process gas passing downwardly through the grate, and in which the hot process gas is generated by combusting fuel while using, as secondary air of combustion, air previously used to cool fired agglomerates. In order to reduce the quantity of gas contaminated during the firing process there is maintained in a sealing zone located between the pre-drying and final-drying zones and mechanically shielded thereagainst, by supplying air above the grate and removing air by suction from beneath the grate, pressures which are substantially equal to the pressure above the grate and the pressure beneath the grate respectively in the adjacent final-drying zone.

Abstract: A variable air flow oven is disclosed in which a variable air directing control means delivers varying amounts of heated air under various positive pressures in an alternating pattern to jet orifices in opposite side walls of the oven in an inverse ratio. Hot air jets from opposite sides of the oven meet at a region of common velocity in the processing chamber to produce a turbulent mixing of the hot air in a vertical plane. The turbulent heated air travels from one side of the oven to the other substantially throughout a heating period under the controlled operation of a motor driven mechanical linkage arrangement to assure even baking, cooking or drying of the products being processed through the entire processing chamber in the oven. The system operates at a positive pressure at all times, so that the main supply of heated air flows through one side duct and a smaller volume of heated air flows through the opposite side.

Abstract: A preheating furnace having a furnace chamber for preheating an extended metal piece, comprising a transportation means for the metal arranged in the furnace chamber, at least one treatment chamber in the furnace chamber for containing and treating the metal; at least one pressure chamber in the furnace chamber into which hot gas is blown under pressure; and a plurality of rows of slot-type nozzles arranged laterally symmetrically from the metal and extending through a partition which subdivides the furnace chamber into the treatment chamber and the pressure chamber. The slot-type nozzles adduct hot gas to the metal so that warping of the metal is prevented, and the nozzles have elongated openings disposed with the longer axis of each opening transverse to the longitudinal axis of the metal.

Abstract: An apparatus for heating billets and the like prior to hot extrusion is disclosed. The apparatus includes an elongated, insulated tunnel having an inlet opening and an outlet opening. A conveyor extends through the tunnel from the inlet to the outlet and conveys a plurality of equally spaced, transversely arranged billets in a step-like manner. The conveyor rotates the billets as they are conveyed through the tunnel. A source of high temperature air is connected to a plenum positioned above the conveyor. High temperature air is discharged from the plenum through a plurality of slot-like jets positioned above the billets so that the air directly impinges on the billets. Temperature probes are included for insuring that the billets are biased to one side of the conveyor upon discharge and for sensing the billet temperature to control the air temperature within the tunnel. An unloader is provided for receiving the billets discharged from the tunnel and rotating them through an angle of 90.degree.

Abstract: Heating apparatus for a baking oven or the like wherein product to be heated or baked is conveyed through the oven, and a plurality of heating elements are arranged longitudinally along the path of product movement through the oven, the heating elements each comprising a conductive tube extending transversely across the path of product movement, a burner at one tube end for introducing a combustible mixture therein, and combustion products outlet means at the other tube end for discharge into the oven chamber.

Abstract: An apparatus for shrinking heat-shrinkable sleeves around containers or the like includes at least two diffuser housings mounted respectively adjacent side edges of a conveyor on which containers or other objects having a sleeve thereon are to pass. A cap which defines a tunnel is positioned between the two diffuser housings over the conveyor. Each diffuser housing is provided with a longitudinally extending slot presenting directional discontinuity at its two end portions. The two end portions of each slot may be horizontal, while the control portion of each slot is sloped in a vertical direction and extends from one end portion of the slot to the other. Provision is made to feed hot air through the slots into a tunnel so as to contact the films on the containers or objects moved by the conveyor.