Abstract: The invention relates to a continuous dryer for veneer. In addition to terature sensors near the inlet and middle zones to determine heat demand and to control heat input in these zones, the dryer also has an infrared detector at the exit end to determine surface temperature and thus to determine residual moisture of the veneer. The signal from this infrared detector is processed to give a control signal for blowers in the drying zones near the exit. By this means, more precise and reliable control in final moisture is achieved. Variations in dryer load, initial moisture, wood density, and sheet thickness can be better tolerated.

Abstract: A film stretching machine with tentering hook chain tracks extending through several consecutive processing zones is constructed of preassembled standardized exchangeable structural groups permitting a modular type of construction. These structural groups include venting cells of the same kind which are fully pre-equipped and are arranged along the left and right edges of the film web to be stretched. Exchangeable blower boxes with nozzle fingers or arms having a standardized width are installable between opposite venting cells of a processing zone. The dimensions of the venting cells are matched to the dimensions of typical shipping containers in order to achieve efficient packaging possibilities. The length of the venting cells advantageously corresponds to two or three times a standard spacing of adjustment spindles used for adjusting the spacing of the tentering hook chain tracks. The width of the standardized blower boxes may vary stepwise by twice the width of the venting cells.

Abstract: A thermal treatment system includes thermally insulated housing structure in which conditioning plenum structure and distribution plenum structure are disposed. The distribution plenum is disposed adjacent a treatment zone that extends through the housing, and the side of the distribution plenum adjacent the treatment zone defines an open port region that corresponds in dimension to the length and width of the treatment zone. Seal flange structure extends along the edges of the open port region. Conveyer structure for supporting product to be thermally treated is disposed in the treatment zone in juxtaposition to the open port region of the distribution plenum. A series of sealed chamber units, each of which includes an array of nozzle tubes that provide an array of spaced parallel flow passages through the sealed chamber, close the open port region so that the series of sealed chamber units defines a wall of the distribution plenum adjacent the treatment zone.

Abstract: An apparatus for drying of articles traveling upon a conveyor which utilizes a housing defining a plenum chamber and a drying chamber therein for use in cooperation with a conveyor which enters the drying chamber at a conveyor inlet position and exits the drying chamber at a conveyor exit position. The plenum chamber is separated from the drying chamber by a particularly constructed airflow device which achieves various specific desired airflow patterns depending upon the type of article being carried upon the conveyor traveling through the drying chamber. A blower is included supplying pressurized air for drying to the plenum chamber where the pressure is equalized and applied in this manner to a plurality of slots defined in the airflow control.

Abstract: Referring to process and equipment for the indirect drying of sludge, especially for the drying of wastewater sludge, which may undergo previous mechanical dehydration and/or preheating, it is intended to provide a method that permits utilizing low-value energy for drying purposes while avoiding environmental nuisance. With reference to the process, the problem is solved by drying the sludge under vacuum which is produced by withdrawing the water vapor by means of an injection condenser, the equipment provided for solving the problem comprising a barometric condensor associated with a mechanical sludge dehydrator and at least one sludge drier for indirect drying with an hermetically closed sludge space, the gas dome of the sludge space being connected to the injection condenser through a line for withdrawal of the water vapor.

Abstract: A method and apparatus for heating fibrous mineral insulation material comprises an oven divided into zones, a conveyor for carrying the insulation material through the oven, means for directing hot gases into contact with the insulation material in the first oven zone, first heating means for heating the hot gases, and second heating means, distinct from the first heating means and positioned upstream from the first oven zone for heating the conveyor.

Abstract: A drier for moving and drying textile materials, wherein the material web passes through several sequentially arrayed identical drying zones during the drying treatment which is implemented by fresh air, circulating air and exhaust air. The improvement includes a central exhaust duct which evacuates exhaust air from all drying zones. Preferably, the drier additionally controls the evacuation of the exhaust air from the drier as a function of the moisture in the exhaust air flow. The exhaust duct may also evacuate exhaust air from the first, central or last drying zone through which the web material passes.

Abstract: A steam dryer for pressed fibrous material, such as sugar beet cossettes, has a pressurized, horizontally arranged pipe or drum (1) closed at both ends and provided with a diametrically opposed supply manifold and exhaust manifold piping (5, 6) for the steam. At least one heat exchanger (7) is arranged in a lengthwise half of the pressurized pipe and extends across the entire steam flow-through cross-section. Endless loop screen or mesh belts (8, 8', 8") are arranged one above the other in the other lengthwise half of the pressurized pipe. These belts are driveable in opposite directions for conveying the material to be dried, and to transfer the material from an upper belt to a lower belt. The mesh belts (8) define separation planes between pressure and exhaust chambers (24, 25) which are alternatingly arranged above and below each respective mesh belt.

Abstract: A vertical progressive lumber dryer has a plurality of vertically spaced functional zones through which lumber formed into units pass. Each unit rests atop a base and each layer of boards in the stack is separated by sticker means. Predetermined appropriate operating conditions are selected for the drying medium as well as other parts of the process. After a car has completed the last step within the dryer, it is removed and the dryed lumber sent for further processing.

Abstract: A plant for heat treating animal or vegetable material comprises apparatuses for two-stage or multi-stage heat treatment. A heat medium which is used in a second heat treatment apparatus (2), which follows a first heat treatment apparatus (1), consists of uncontaminated water/steam which is circulated in a closed circuit, that is to say separated from the heat medium of the first apparatus and from the treatment material of the second apparatus. The closed circuit extends from heat exchanger surfaces, which are supplied with heat energy from exhaust gas/exhaust steam from the first apparatus (1), via heat surfaces of the second apparatus (2) back to said heat exchanger surfaces. The closed circuit includes one or more steam compressor(s) (17) in order to bring in a manner known per se the heat medium of the circuit up to the process steam pressure before it is supplied to the heat surfaces of the second apparatus (2).

Abstract: A method and apparatus for heating selected portions of an article include transport means for moving the article into a heating compartment. Shroud means, which are disposed within the heating compartment and located adjacent to limited portion of the article, direct a stream of heated gas toward a marginal portion of this article. Supply means deliver a volume rate flow of heated gas to the shroud means, and discharge means remove a volume rate of exhaust gas flow from the heating compartment. The discharge means is constructed and arranged to provide a volume rate of exhaust gas flow from the heating compartment which is greater than the volume rate of heated gas flow supplied into the shroud means.

Abstract: An apparatus for drying nodular, granular and other products includes a vessel containing an evacuated chamber and an endless belt conveyor that passes through the chamber. Microwave energy is supplied to the chamber by several microwave generators, with each generator supplying energy for a different zone along the belt. The moisture-laden product is introduced into the chamber without affecting the pressure within the chamber, and is then distributed onto the conveyor belt at uniform thickness and width. The belt transports the product through the zones of microwave energy, and within each zone the strength of the field is below the breakdown point of the field for the particular pressure of the chamber, so the destructive effects of ionization are avoided. By reason of the greater moisture content in the product at the first zone, more energy can be supplied to the product in that zone, and indeed the energy supplied diminishes with each successive zone.

Abstract: A processing system for batches of different products in the same conditions, and having chamber means having zones, air circulation for each zone, and tempering for tempering the air zones, to produce uniform conditions within each zone, first and second separate side by side conveyors passing through the chamber, batch supports movable on respective first and second conveyors, for carrying batches of compatible products, conveyor movement for moving said separate batch supports at different speeds, and different timings, to procure different transit and dwell times of different products within the same zones of the chamber, and, control means connected to the conveyor.

Abstract: An operation wherein a large amount of material is passed through the nip of two rolls and a dryer at high speed using only a small specimen of material is disclosed. A low mass carrier for the specimen is provided. The carrier and specimen are quickly accelerated to the peripheral speed of the rolls and the specimen is passed through the rolls and quickly stopped inside a static dryer. Specific apparatus for carrying out each step of the operation is disclosed.

Abstract: An apparatus for sterilizing containers such as bottles and vials for the pharmaceutical industry, in the form of a tunnel continuously traversed by a conveyor belt for said containers, comprising a sterlization chamber which utilizes a hot air stream in the laminar flow regime and is provided with air filters, characterized in that in said sterilization chamber the heated air is fed to a pressure chamber communicating in a sealed manner with said filters, and from these latter on to said containers to be sterilized, between said pressure chamber-filter system and walls of the sterilization chamber there being defined a jacket for recirculation of the air, in which the pressure is kept at a lower value than the pressure present in said pressure chamber-filter system.

Abstract: A process for dewaxing a mold for use in lost wax casting is proposed, wherein the mold is loaded on a pallet which is placed and then securely held on a carrier which is rotatably assembled in a dewaxing tank. The mold is inverted to be ready for dewaxing within the tank and then returned to the initial condition within the tank by rotating the carrier by about 180 degrees at a time.An autoclave for use in the process comprises a carrier framework rotatably disposed within a dewaxing tank for carrying a pallet loaded with shell mold trees. The carrier framework is held in a first position for assembling the pallet and then is rotated by about 180 degrees to a second inverted position to hold the pallet securely in the inverted condition during the dewaxing operation.A preferred embodiment of the autoclave further comprises means for securely fastening the pallet and the mold trees automatically and simultaneously with the operation of sealingly closing the entrance opening of the dewaxing tank.

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: In a method of and apparatus for heat-drying of webs, especially printed or inked webs, the web is first subjected to a contactless heat shock treatment, for example by hot air at about 300.degree. C. It is then heated by a contact process at a lower temperature, for example by heated rollers at about 230.degree. C., after which it is cooled by a contact process in a third step. Each of the heated rollers may have associated therewith a roller for applying a film of a buffer agent and also a cleaning roller. Energy expended in the processes is recovered by the use of heat exchangers. The apparatus may comprise a closed housing divided into separate chambers within which the sequence of steps is carried out.

Abstract: A cell for degassing of residual olefin oxide from an olefin oxide sterilized product. The product is fed through the cell on a gravity conveyor using a combination of heat, retention time and air change rate optimized for a particular product. A pallet containing the product to be degassed rolls to a preselected position within the cell. The pre-selected position is established by automatically controlled stops appropriately located on the gravity conveyors. The cell is dedicated to a specific sterilizer product load and can be arranged in a modular fashion with a minimum internal volume.

Abstract: In a peripheral exhaust system for a high velocity dryer having dryer hood sections and respective supply and removal ducts associated with each section through which recirculating air used for drying is carried to and away from the sections, auxiliary exhaust ducts formed along the periphery of the sections adapted to receive a portion of the hot air used for drying that would otherwise enter the area surrounding the dryer hood and a portion of the cold air from the surrounding area that would otherwise enter the dryer hood. The exhaust ducts are connected by blowers to ducts which remove the air to a location remote from the web.

Abstract: An impingement oven wherein a carrier-type conveyor passes between hot air plenums located above and below the conveyor. Horizontally adjacent plenums have their fans located in an off-set position to overhang the other one of the pair. Each plenum has a nozzle plate to direct heated air toward the conveyor so that the air flow is substantially perpendicular to the conveyor and such workpiece(s) as may be thereon. An oven module having four sets of plenums and four conveyors in the same enclosure is described. A plurality of such modules serially arranged provide a multizone oven. The oven is especially suited to heating flat workpieces of thermoplastic resin which are to be processed elsewhere into hollow objects such as containers.

Abstract: Disclosed is a chamber which defines a constant gas flow environment for passing objects therethrough carried by a conveyor. The chamber comprises an elongate housing having an inlet opening and an outlet opening in the longitudinal direction and a moving conveyor which runs the length of said housing for transporting object from said inlet opening through said housing and thereout through said outlet opening, the space below said conveyor being enclosed and connected to a source of exhaust for exhausting gaseous substances therein. The space above the conveyor comprises an inlet zone, a central gas zone, and an outlet zone. The inlet zone and the outlet zone both are of a bi-cameral containment arrangement comprising an outer adjustable gate for determining the inlet opening, a central adjustable baffle gate, and an inner deflector wall. The space between the outer gate and the baffle gate is connected to a source of exhaust.

Abstract: A method and an apparatus for drying a paper, or similar, web so that a wet web and a drying felt or wire are subjected to an air removal treatment, the web and the felt or wire freed of air are passed between moving surface elements having good heat conducting properties, said elements enclosing the web and the felt or wire along the whole width, the surface element contacting the web is heated in order to evaporate water contained in the web, and the surface element contacting the felt or wire is cooled in order to condense vapor emanating from the web into the felt or wire, and the felt or wire are separated from the dried web.

Abstract: A continuous drier for plywood sheets is provided at its inlet end with a nsing device measuring the width and the spacing of the plywood sheets entering the drier. The values measured by the sensing device are transmitted to a control device, which by means of a calculator regulates the speed of a conveyor transporting the plywood sheets through consecutive sections of the drier in such a manner that the plywood sheets follow each other closely on the conveyor without overlapping. Each of the sections is provided with a heater and a ventilator which blows air over the heater, and the hot air is directed by installations onto the plywood sheets. In order to compensate the effect of the varying speed of the conveyor with respect to the drying of the plywood sheets, the control device preferably controls also the volume of the streams of hot air by varying the speed of the ventilators. This will result in a considerable saving of the driving energy.

Abstract: Disclosed is a chamber which defines a constant gas flow environment for passing objects therethrough carried by a conveyor. The chamber comprises an elongate housing having an inlet opening and an outlet opening in the longitudinal direction and a moving conveyor which runs the length of said housing for transporting object from said inlet opening through said housing and thereout through said outlet opening, the space below said conveyor being enclosed and connected to a source of exhaust for exhausting gaseous substances therein. The space above the conveyor comprises an inlet zone, a central gas zone, and an outlet zone. The inlet zone and the outlet zone both are of a bi-cameral containment arrangement comprising an outer adjustable gate for determining the inlet opening, a central adjustable baffle gate, and an inner deflector wall. The space between the outer gate and the baffle gate is connected to a source of exhaust.

Abstract: Method of and apparatus for use in drying materials in a dryer through which the material is conveyed and there subjected to heat which decreases from a maximum adjacent the infeed end of the dryer to a minimum adjacent the outfeed end thereof. A controlled small volume of air is forced towards the infeed end of the dryer from the outfeed end thereof and is repeatedly brought in contact with the conveyed material substantially without added air and with the percentage of moisture carried thereby increasing until, adjacent the infeed end, a high level of sensible heat is available to effect the heating of the material and the removal of its moisture which is carried through a heat exchanger in the exhaust. The heat is recovered from the moisture laden exhaust by the heat exchanger in a manner enabling the temperature of the air when exhausted, to be at a wanted level and the recovered heat used to increase drying efficiency.

Abstract: Device for the continuous dehydration of products of the type comprising a stack of endless belts, travelling in alternate directions, characterized in that, on the one hand, only one (33) of the ducts (33, 34) is provided with a heating means (14) and with a fresh air intake (32), and in that, on the other hand, at each belt level (1, 2, 3, 4 or 5) there is distributed a mixture of a portion of air coming from the circuit with reheating through a first opening (20, 21, 22, 23 or 24) and another portion of air coming from the circuit without reheating through a second opening (27, 28, 29, 30 or 31), the ratio of cross-sections between the first and the second opening being progressively variable and constantly diminishing from the top level (1) down to the bottom level (5).

Abstract: An energy efficient method of drying and curing insulation on wire, especially magnet wire, is disclosed. Heated gases are used separately to dry and cure a curable insulating coating such as a phenolic resin. Gases exhausted from the drying and curing operations and containing volatile combustible materials evolved from the drying and curing of the coating, is passed to a heat exchanger where they pick up heat from the exhaust gases of a fume burner. The hot gases are then passed to the fume burner where the combustible materials are burned to add heat of combustion to the gas stream, which is then cycled back as the fume burner exhaust through the heat exchanger, mixed with air, and passed to the drying section of the wire oven. This recapture of the heat from the combustion provides the heat needed for drying of the coating, thus maximizing the energy efficiency of the process. Apparatus to perform the process is also disclosed.

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 gas flows through a pipe employed for intensive heat and material transfer, wherein the pipe has a length equal to 0.5 to 100 meters. The pipe features a gas inlet and two gas outlets. A solid body charge interacting with the gas flow enters at an inlet position in the pipe, passes a plurality of baffles which reduce the cross section in the pipe, and emerges from the pipe at the end position. Together with the surface of the solid body charge, the baffles form gaps of 3-50 mm which reduce the boundary layer of gas on the charge limiting the heat or material transfer. Between each pair of neighboring baffles are chambers in which the gas rotates and thus strikes the charge repeatedly. As a result the efficiency of material and heat transfer is further improved. With this countercurrent system the solid body can take up and release heat during its passage through the pipe and can take up or release material according to the character of the gas flowing in the inlet.

Abstract: A dryer for reducing the moisture content of material in sheet form comprising a drying chamber through which material to be dried is conveyed and through which heated air is recirculated being withdrawn from the material exit end thereof at less than atmospheric pressure and returned to the material feed end of the drying chamber by power driven fans. During its return to the material feed end of the drying chamber it is reheated. A supplemental gas chamber is provided at the feed end of the drying chamber for controlling the flow of gas from the material feed end of the drying chamber. A second supplemental gas chamber at the material exit end of the drying chamber has means for limiting the leakage of air at ambient temperature thereinto and is provided with an exhaust fan for withdrawing gas therefrom and in turn from the material exit end of the drying chamber.

Abstract: A housing having propeller type fans in the housing adjacent to an object or objects to be dried. Shafts, carried by sleeves projecting through the side walls or top wall, rotate the fans. Motors externally of the housing drive the shafts.In one form of the invention, the air circulated by the fans is heated by steam coils adjacent to the periphery of the blades of the fans. In another embodiment, an open flame gas or oil burner, disposed in a combustion chamber, heats air, which is subsequently directed by ducts to the fans. Exhaust blowers and exhaust ducts exhaust the fume laden air from the chamber. Still another embodiment shows pairs of juxtaposed oppositely blowing fans carried by shafts protruding through the walls of the oven and spaced heaters between the fans. Still another embodiment shows opposed fans for drying a cylindrical member passed through the chamber.

Abstract: An arrangement for drying plate-shaped wood products, such as veneers and plywood plies, includes a roller conveyor which advances the products in the leading portion of their drying path, and a belt conveyor which advances the products in the trailing portion of such path. The two conveyors are accommodated in separate housings. The roller conveyor includes a plurality of pairs of rollers which confine the wood products therebetween and thus smoothen the same, while the belt conveyor includes at least two conveyor belts which confine the wood products between themselves but do not interfere with the shrinking of the material of the products as the same are being dried. A transition or transfer device, such as a roller table, is arranged between and aligned with the roller and belt conveyors to let the material of the plate-shaped wood product get rid of the stresses which have built up therein during its passage through the roller conveyor section.

Abstract: A conveyorized, electrically heated oven provides controlled top and bottom heating for pizza or other food products. Cooking is accomplished in two ways. The top of the food is cooked with heated air circulated within the oven, while the bottom of the food is heated by electric heating elements located between live conveyor rolls. Heated air within the oven is recirculated. In the preferred embodiment of the invention, two parallel conveyor lines are provided, with controls to permit use of one or both lines. Because of the heat recirculation system, the oven does not require a heat vent and energy consumption is reduced.

Abstract: Moist pourable material which is required to be in dry condition, is dried by heating and drying a portion of the material and then mixing this portion with the remaining moist portion, so that the heat of the heated dry portion will heat and dry the remaining portion. A method and an apparatus are disclosed.

Abstract: A fruit dryer comprising a roller conveyor passing through an elongate drying chamber is disclosed. An air plenum having a plurality of transverse nozzle openings is disposed above the conveyor and directs a series of curtain-like air streams on the fruit below. The major portion of the air within the dryer is recycled by a fan while a smaller portion of said air is exhausted by a second fan. A heater heats both the recycled air and fresh air introduced as make-up for the exhausted air. A means is provided to rotate the individual rollers of the roller conveyor as the conveyor is advanced in order to expose all sides of the fruit to the air streams.

Abstract: An oven is disclosed as having a plurality of chambers which are sealed from the ambient atmosphere, and to which gas, heated to a high temperature outside the chambers, is circulated to each of the chambers for admixture with gas which is cool compared to the high temperature gas, to produce in the chambers a mixture of hot and cool gas at a predetermined temperature. The hot gas is circulated to the chambers at a certain desired pressure, wherein the cool gas is circulated to the chambers at a certain rate of flow. Gas is exhausted from the oven also at a fixed rate of flow. The gas pressure in the first oven to be encountered by an element passing through the oven, is monitored and triggers a change in the flow of cool gas when the pressure varies from a desired norm. This change in flow of cool gas influences the temperature which is also monitored. A change in the temperature produces a corresponding change in the mixture of hot and cool gas to return the oven temperature to the desired level.

Abstract: An apparatus for drying fruits or other products comprises a drying unit and a connected cooling unit having conveyors therein for moving products to be dried from the cooling unit through the drying unit and then back to the cooling unit in a succession of cycles. Hot air from a heating unit is supplied to the end of the drying unit adjacent the cooling unit, and is directed through the drying unit away from the cooling unit for exhaust from the end of the drying unit remote from the cooling unit whereby, as the products being dried move through the drying unit away from the cooling unit they pass successively through air which is increasingly less hot and less dry and as said products thereafter move through the drying unit back toward the cooling unit they pass through air which is increasingly hotter and drier before reaching the cooling unit to start a new cycle.

Abstract: An apparatus for the heat treatment of a material passing through a plurality of treatment zones using a heated gaseous treatment medium conducted in a substantially closed circuit through these zones. A heat exchanger is associated with each treatment zone. The heat exchanger defines, in an operative relation with the respective treatment zone a medium discharge path and a medium replacement path which paths are arranged in a heat exchange relationship. The fractional portion of a treatment medium discharged from each treatment zone transfers its heat and energy to the fresh replacement medium. A throttle or flow control in the medium replacement path for each treatment zone permits individualized control of draft and medium turnover according to the different conditions prevailing in each zone. A filter is also provided to prevent impurities in the medium discharge flow path from entering the heat exchanger.

Abstract: Wet plasterboard to be dried is advanced along a path. At an upstream portion of the path, air is heated and directed towards the plasterboard for initial drying of the latter. A portion of the heated air is withdrawn and passed through one section of a heat exchanger whose other section contains water which exchanges heat with the heated air. The heated water is passed through a section of another heat exchanger whose other section contains fresh air which is heated by the heated water. The heated fresh air is directed towards the articles for further drying of the latter at a downstream portion of the path. A portion of the heated fresh air is exhausted and recirculated at the downstream path portion.

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: A continuously operating multistage drying installation is provided for drying a workpiece. The drying installation includes a conveyor belt for transporting along a predetermined path a workpiece having two opposite longitudinally extending surfaces and containing excess moisture. A first stage drier is located at an upstream portion of the path. This drier includes guide rollers for turning the workpiece over at least once so as to expose both of its surfaces to heat within the drier to thereby preliminarily dry the workpiece. A second stage drier is provided at the path downstream of the first stage drier for finishing the drying of the workpiece to a desired moisture level while maintaining the workpiece free from being turned over to thereby avoid cracking the surfaces of the workpiece due to pressure applied to the demoisturized and consequently relatively brittle surfaces thereof.

Abstract: An oven, having a series of separate and isolated chambers which are horizontally aligned and sealed from each other and the ambient atmosphere and through which a continuous element is passed for treatment by heated gas within the chambers, is disclosed. The oven is provided with means for circulating heated gas to the chamber of the oven last-to-be-encountered by the element and cascading such heated gas successively through the other chambers to the first chamber to be encountered by the traveling element, or in an upstream direction relative to the travel of the element. Thus, the source of heated gas for a particular chamber is from the next succeeding downstream chamber which is contrary to present day ovens wherein each chamber is normally supplied with its own burner system for separately temperature conditioning gas circulated to that particular chamber.

Abstract: A method and apparatus for drying articles, such as fruit, which are treated with an aqueous coating such as a wax composition to preserve and to enhance the appearance of the article. The drying apparatus comprises a plurality of housing sections, each providing substantially closed chambers through which a conveyor means carries and advances articles to be dried at a selected rate of speed. The conveyor and a strata of articles carried thereon form a perforate zone in each housing section. Drying air is directed downwardly into a side passageway means at one side of each chamber to pass into a plenum chamber below the conveyor means and to then flow upwardly and substantially uniformly through the conveyor means and strata of articles thereon. Drying air is drawn from an upper chamber above the conveyor means by a blower which directs the drying air into side passageway means downwardly and into the plenum chamber of the next adjacent downstream housing section.

Abstract: A lateral exhaust manifold system for the preheat section of a tunnel kiln comprises a longitudinal duct and input tube. The duct is triangular in shape and has a plurality of spaced apart apertures and a corresponding plurality of cones, the large diameter end of each cone circumposing a respective one of said apertures. The input tube is disposed adjacent the opposite side of the tunnel kiln and has a plurality of spaced apart jets each disposed opposite a respective aperture in the longitudinal duct, and a plurality of spaced apart apertures each located intermediate the jets, the spaced apart apertures and for venting air laterally across the kiln and upwardly along the adjacent wall. A blower vents an exhaust stack connected to an end of the duct. Air curtains control the entrance and exit of the preheat section of the kiln.

Abstract: A steam lock is connected to the processing chamber in which textile goods are treated with an organic solvent which is immiscible with water. The web of material is led through this lock. This steam lock consists of an evacuation chamber which is separated from the processing chamber by a pair of sealing lips, of a plurality of steam chambers which are separated from each other and from the evacuation chamber by constrictions, and of a compensating chamber which is also separated by a constriction from the steam chambers. All the chambers are connected to a condenser and a water separator by means of a suction duct. The steam chambers are equipped with steam pipes which are adjustable and provided with slit nozzles, and superheated steam is supplied to these steam pipes.

Abstract: A roller tunnel kiln for firing a drying refractory material advanced along the refractory rotatable rollers includes an upper section comprising a prefiring zone, a firing zone, a first forced cooling zone, a natural cooling zone and a second forced cooling zone. Parallel to the upper section along the length thereof a drying zone is arranged provided with refractory rotatable rollers for advancing movement of the material to be dried. A distributional tunnel is mounted parallel to the drying zone and is connected with the prekiln zone or with the forced cooling zone so that hot gases mixed with cool ambient air are directed into the distributing tunnel provided with openings communicating the latter with the drying zone. The hot gases at drying temperatures are further directed into drying tunnel in the direction opposite to that of the material to be dried.

Abstract: A method of heating a fleece comprises supporting the fleece on a perforate fleece carrier and passing a heated gas through the fleece and fleece carrier, preferably in that sequence to assist compaction of the fleece. Apparatus for performing this method comprises two chambers between which the fleece is passed on the carrier, the chambers being maintained at different pressures by a fan to create the flow through the fleece and through a radiator for heating the gas. The gas may be recirculated and may be filtered and/or augmented by a further supply. A roller at the exit end of the chambers compresses the heated fleece, preferably from above. The fleece carrier may be preheated upstream of the heating station, for example by induction heating in the case of a metal fleece carrier. A freely running roller having adjustable height rests on the fleece and seals the entry to the heating station.

Abstract: An apparatus and method for removing moisture from a porous textile web. The web is passed sequentially through a plurality of drying regions, dividing each of the drying regions into an upper drying zone and a lower drying zone. Air is drawn through the traveling web by variable speed fans disposed in the drying regions, the air forced by each of the fans into an air passageway having fluid communication with all of the upper drying zones and separated into air channels by divider panels.

Abstract: A method and apparatus for drying timber stacked in a vertical kiln in spaced apart layers. The timber being continuously moved from the top to the bottom of the stack to be passed through various stages of treatment including a drying in which the timber is subjected to reverse process of heated air. The bottom layer is periodically removed from the stack and a new green layer added to the top.