Abstract:
A convective hood for transverse installation in a system for continuous heat treatment of moving strip material comprises blowing nozzles for blowing hot gas against the moving strip in an arrangement transverse to the direction of movement of the strip material; and a first transverse suction zone for the suction of hot gas. The first transverse suction zone comprises a first transverse section and a second transverse section. The first transverse section and the second transverse section are provided at the same side downstream or upstream of the movement of the strip material from the blowing nozzles when the convective hood is installed in a system for continuous heat treatment of moving strip material. The second transverse section is provided along the line for movement of the continuous strip material between the first transverse section and the blowing nozzles. The first transverse section comprises suction openings for suction of hot gas directly from outside the convective hood into the convective hood; the suction openings being in closed gas flow connection to a first manifold for recirculation of at least part of this hot gas to the blowing nozzles for blowing the hot gas onto the continuous strip material. The second transverse section comprises suction openings for suction of hot gas directly from outside the convective hood into the convective hood; the suction openings being in closed gas flow connection to a second manifold for exhausting 100% of this hot gas outside of the convective hood.
Abstract:
A cross-direction web dryer includes an elongated frame arranged transversely across a web of moving paper. The support structure carries a plurality of movable dryer modules which are relocatable over the worst moisture streaks occurring in a moving web. In addition, a technique is provided for cooling the movable dryer modules, as well as supplying them with needed electrical heating power and control cables.
Abstract:
A drier installation (1) for drying web (2), more particularly paper, which installation is provided for drying a maximum web width, the installation (1) comprises gas-heated radiant elements (3) for radiating the web, arranged according to at least one row (4) stretching out in the transversal (5) direction over the substantially entire maximum web width. The installation (1) comprises at least a transversal convective system (7, 36) equipped with suction and blowing devices (8) for sucking at least part of the combustion products produced by the radiant elements (3) by means of a suction duct (13) and for blowing this pa o the combustion products towards the web (2) by means of a blowing duct (14). Both suction (13) and blowing (14) ducts stretch out in the transversal (5) direction of the web (2). The convective system (7, 36 comprising at least a mixing device (12, 22, 28, 37, 46) installed opposite of the passing web (2) in relation to corresponding suction (13) and blowing (14) ducts and arranged so as to suck and/or blow the combustion products. The drier installation as subject of the present invention is characterized in that the vector average of the projections (V1, V2, V3, V5, V6, V7, V8) in a plane (P1) perpendicular to the web ( ) and stretching out in the transversal (5) direction of the web (2), has component (V4) parallel to the web (2) that is smaller than the maximum web width of the web (2), the vectors representing the respective trajectories of the different jets of sucked and/or blown combustion products.
Abstract:
In order to adapt a gas-infrared radiator (a radiant burner) to operating conditions in a particularly efficient manner, the energy delivered is reduced by intermittently reducing a controlled supply of gas so that the energy delivery is below about 40% or even less of the maximum energy delivery of the infrared radiator, and a flame supplied separately from the controlled gas supply is maintained in the combustion chamber of the gas-infrared radiator, at least when operating in the aforementioned range. This is achieved more particularly by providing at least one nozzle (22) for a pilot light, directed towards the combustion chamber (4).
Abstract:
A cross-direction web dryer includes a support structure arranged transversely across the moving web consisting of a pair of elongated support members each carrying side-by-side heater modules facing the moving web. This pair of structural members may be moved from the above operating position by a rotating and pivoting action to a stowed position where the heater elements are juxtaposed and co-extensive with one another to effectively thermally capture the heat of the heater elements. This reduces the heating up of the surrounding area while the heater elements cool down and prevents paper scrap and other flammable products from igniting that could create a fire hazard.
Abstract:
Methods and apparatus for rapidly drying and compacting wet fiber mats are disclosed. Rapid drying is produced by heating the wet fiber mats with a combination of radiowave energy and conductive heating. As the fiber mats are heated, three-dimensional compacting forces are applied by pressing the fiber mats between a flat surface press and a porous support on which is mounted a resilient mold insert. At high radio frequencies in the microwave range, power is transmitted from a multimode cavity through the porous support and resilient mold insert to the fiber mat. At low radio frequencies, differential radio-frequency voltages are applied directly to metal press plates which contain and compact the fiber mat. Methods and apparatus can be adapted to conveyorized or multi-opening press operations. Objects suitable for use with the invention are most commonly characterized by having a flat face surface on one side and webs or other features which may extend normal or generally normal to the flat surface.
Abstract:
In order to adapt a gas-infrared radiator (a radiant burner) to operating conditions in a particularly efficient manner, the energy delivered is reduced by intermittently reducing a controlled supply of gas so that the energy delivery is below about 40% or even less of the maximum energy delivery of the infrared radiator, and a flame supplied separately from the controlled gas supply is maintained in the combustion chamber of the gas-infrared radiator, at least when operating in the aforementioned range. This is achieved more particularly by providing at least one nozzle (22) for a pilot light, directed towards the combustion chamber (4).
Abstract:
A drier installation (1) for drying web (2), more particularly paper, which installation is provided for drying a maximum web width, the installation (1) comprises gas-heated radiant elements (3) for radiating the web, arranged according to at least one row (4) stretching out in the transversal (5) direction over the substantially entire maximum web width. The installation (1) comprises at least a transversal convective system (7, 36) equipped with suction and blowing devices (8) for sucking at least part of the combustion products produced by the radiant elements (3) by means of a suction duct (13) and for blowing this pa o the combustion products towards the web (2) by means of a blowing duct (14). Both suction (13) and blowing (14) ducts stretch out in the transversal (5) direction of the web (2). The convective system (7, 36 comprising at least a mixing device (12, 22, 28, 37, 46) installed opposite of the passing web (2) in relation to corresponding suction (13) and blowing (14) ducts and arranged so as to suck and/or blow the combustion products. The drier installation as subject of the present invention is characterized in that the vector average of the projections (V1, V2, V3, V5, V6, V7, V8) in a plane (P1) perpendicular to the web ( ) and stretching out in the transversal (5) direction of the web (2), has component (V4) parallel to the web (2) that is smaller than the maximum web width of the web (2), the vectors representing the respective trajectories of the different jets of sucked and/or blown combustion products.