Abstract: A roller tunnel kiln includes a lower kiln body half composed integrally of a kiln bottom and a pair of transversely spaced lower kiln side wall halves which are made of refractory brick, a pair of endless chains disposed respectively on transversely opposite sides of the lower kiln body half outside thereof, the endless chains being movable forward along the lower kiln side wall halves at a height substantially equal to upper ends of the lower kiln side wall halves and movable backward along the lower kiln side wall halves at a height lower than the kiln bottom, a drive device for driving the endless chains in synchronism with each other, couplings mounted at regular intervals on link plates or link pins of each of the endless chains, feed members having opposite ends gripped by respective couplings and movable in a longitudinal direction of the lower kiln body half directly thereabove in response to the endless chains being synchronously driven, the feed members being made of a heat-resistant material and h

Abstract: An apparatus for heat treating a work item includes a cover member and a base member on which the cover member is supported. A work space is defined between the base member and the cover member for receiving at least one work item which is positioned therein. A seal member is located between the base member and the cover member for sealing the work space against the entry and exit of gas. A valving system is provided for regulating the entrance and exit of a gas to and from the work space. The valving system is in fluid communication with the work space and includes a relief valve member for allowing the exhaust of the gas from the work space when gas pressure therein exceeds a predetermined limit.

Abstract: A fixture for holding wing structures during heat bonding of their skins, the wing structures each including a base along the root thereof defined by a pair of elongated base flanges and an elongated slot extending into the root centrally between the base flanges. The fixture comprises an elongated, rigid member including an elongated surface portion curved at a predetermined radius which tapers from approximately the central area of the member to one end thereof toward the axis of the member to induce a distortion in the wing structure sufficient to compensate for thermally induced dimensional changes in the wing structure after removal from the fixture. The fixture also includes an elongated key flange radially extending from the curved surface portion for cooperating with a slot in the base of the wing structure to align the wing structure with the longitudinal axis of the member and screws for securing the base flanges of the wing structure to the curved surface on opposite sides of the key.

Abstract: A refractory block design for re-radiating a substantial amount of heat losses back to a heated product thereby substantially maintaining its required temperature. A relatively thin sheet of stainless steel, i.e. the ratio of the thickness of the sheet being approximately 1/500th of the thickness of the heated product, is wrapped in a sinuous manner around one side of a refractory fiber block arranged in a similar sinuous manner to tightly fit into the folds of the block for storing heat, and radiating heat back to the heated product when thermal equilibrium therebetween is reached.

Abstract: In an apparatus for treating workpieces by means of the igniting of a gaseous mixture in a work chamber for receiving the workpiece, it is proposed that the work chamber and optionally the supply duct for the gaseous mixture, as well as a mixing block for preparing the gaseous mixture which precedes the supply duct, are provided at least in part with a lining of ceramic material in the form of aluminum oxide or zirconium dioxide, in order to intercept the corrosive action exerted by the ignition of the combustion gas-oxygen mixture upon these parts of the apparatus.

Abstract: A method and an apparatus for continuously annealing cold rolled steel strips successively passing through a preheating zone, a low temperature heating zone, a high temperature heating soaking zone, a primary cooling zone and a secondary cooling zone. In each zone, the steel strip is driven by hearth rolls alternately upward and downward in a serpentine path. According to the invention, in a high temperature zone such as the high temperature heating zone and the primary cooling zone where the steel strip is prone to heat buckling, the steel strip is caused to pass only once in a single direction without passing along the serpentine path, thereby preventing meandering and heat buckling of the steel strip.

Abstract: In reheating and conveying a granular heat carrier, such as sand, which is transportable by a gas and is used for desorption by heating a charged lumpy adsorber, such as activated carbon pellets, the sand is passed upwardly in a cylindrically shaped pipe element in the form of a fluidized bed. The sand is heated during its upward passage through the fluidized bed. Air introduced into the lower part of the pipe element is used as the fluidizing medium and also as combustion air. Further, fuel is supplied into the lower part of the pipe element. From the upper end of the pipe element, the heated sand flows downwardly by gravity to a sand separator, where it is separated from flue gas, into a desorber where it is contacted by the absorbent and then into a device for separating the sand and the adsorbent so that the sand can be returned into the lower end of the pipe element.

Abstract: A food preparation oven for baking foods which require less heat energy input into a first surface than into a second surface such as pizzas. A radiant panel is provided which is heated by means of hot air and which is positioned to heat one surface of the food product by radiant heat energy. The second surface of the food product is heated by means of a flow of hot air. The air is heated in a heating chamber and recirculated by means of a fan. The food product is supported on a conveyor belt and travels through the food preparation oven while it is being baked.

Abstract: Tendrillar carbonaceous material is used as a fluidization aid for fluidized beds. The tendrillar carbonaceous material can be used to fluidize cohesive solids. Further, it can be used to improve fluidization of particulate solids by reducing entrainment, eliminating bubbling, and/or eliminating channelling. The tendrillar carbonaceous material can be a fibrous, particulate carbonaceous material comprising carbon fibers and a ferrous group metal component dispersed throughout the carbon fibers as nodules. The tendrillar carbonaceous material has a bulk density of from about 0.04 to about 0.7 g/cm.sup.3 and comprises an agglomeration of tendrils having a diameter of from about 0.01 to about 1 micron and a length to diameter ratio of from about 5:1 to about 1000:1.

Abstract: A device is suggested wherein the work piece finishing chamber (31) serves simultaneously as a mixing chamber for mixing the gas components, and wherein a gas deceleration stage (47) is integrated in chamber block (30) between chamber (31) and a spark plug (54). The gas deceleration stage (47) is provided with labyrinth like extending bores (49,50,51). The combustion residues generated in the work piece finishing chamber (31) cannot reach spark plug (54) in view of the gas deceleration stage (47). Thus, a contamination of the spark plug (54) being disposed in block (30) is substantially eliminated.

Abstract: In a heat treatment furnace with a circular charge conveyor system, bar-shaped charge support elements are provided and said support elements are mobile with respect to each other both in a vertical direction and in the direction of charge travel. Said support elements are arranged substantially in a radial direction and/or in a circle or in sectors of a circle. Several such charge support elements arranged radially are preferably assembled to form fork-type elements. Said support elements may also be arranged in a plurality of vertical planes to form a continuous or a discontinuous helical-type charge conveyor system. The present invention increases throughput, if compared with a conventional furnace of the same size, reduces energy requirements and thus improves conventional pusher-type furnaces for heat treatment in a controlled atmosphere.

Abstract: Apparatus and method for continuous freeze drying in which a slurry of material to be freeze dried is provided. The slurry is advanced along a predetermined path having a freezing area in which one or more plugs of frozen slurry are provided to afford a pressure drop. Heat is applied to the frozen slurry as it exits into an area of reduced pressure. The heat and reduced pressure cause the frozen slurry to sublime.

Abstract: A heat exchanger for heating air supplied to a burner is described. The heat exchanger includes two passages. One of the passages provides a channel through which combustion gas is exhausted from the burner while the other passage provides a channel through which air is supplied to the burner. The two passages are arranged to transfer heat from the combustion gas to the combustion air. Each of the passages includes a helical guide baffle for directing fluid through each respective passage substantially along a helical flow path. The helical guide baffles of the passages each exhibits a variable pitch which changes at a predetermined rate to maintain the pressure and velocity of the fluid in the respective passages within predetermined limits.

Abstract: A sheet of a cross-linkable and foamable polyolefin resin is thermally treated on an endless conveyor belt formed of a plain weave wire net. A plurality of parallel, spaced apart rolls are disposed in a direction perpendicular to the direction in which the conveyor belt runs for supporting engagement and rolling contact with the conveyor belt to maintain the flatness of the conveyor belt.

Abstract: Improved techniques for infra-red generating gas-fired burners to heat-treat substrates with or without the added heating effects of the hot combusted gases generated by the burners. Burners can have ceramic fiber mat held over shallow combustion mixture plenum essentially completely spanned by baffle. Mats can have folded-in edges to permit close packing. Plenum can have partition forming small ignition compartment with igniter against covering portion of mat.

Abstract: A thermocouple probe assembly for a billet furnace is provided with replaceable contact tips joined to the shanks of the probe rods within a surrounding insulator to inhibit oxidation of the junctions. Two pairs of probes are used, each pair being associated with an independent control circuit as a safety backup system. The assembly is preferably mounted on a bracket that is extendable on an angle forty-five degrees to the horizontal to provide correct probe positioning for various sizes of billets, and has a heat shield correspondingly adjustable along the probe assembly to accommodate various degrees of penetration of the probe assembly into the furnace.

Abstract: A rotary kiln has a number of thermocouples respectively sensing the kiln temperature at spaced locations and respectively connected to annular slip rings each in kiln sections. Laterally facing peripheral surfaces of the rings are respectively cooperable with brush contacts connected to a bar and a fork which embraces a ring moveable axially with the rings. Thus, on longitudinal expansion of the kiln the contacts are caused to move with the rings. The electric signal from the thermocouples are fed to a stationary sensor. In a modification the ring sections are electrically isolated and each section is connected to a respective sensor. Position sensors may be used to detect the rotary position of the kiln. The invention can be applied to other sensors.

Abstract: A method of flattening a stack of sheets of material by assembling the stack horizontally in an oven of clamshell like construction and applying pressure to the stack hydraulically from an external pressure source by means of pistons entering the oven from each end.

Abstract: A multi-zone furnace having one or more walking beam conveyors operative in association with movable isolation doors to provide selective isolation of furnace zones and efficient transport and processing of a product through successive furnace zones.

Abstract: In an installation including a heating furnace in the rolling mill and a continuous casting apparatus, there is provided a transportable temperature holding chamber for the castings which are cut to length, in which chamber the castings are transported in groups from the continuous casting apparatus to the heating furnace, and are stored temporarily in the buffer mode. That makes it possible to save energy and to improve the quality of the steels.