Method for on-machine coating-drying of a paper web or the like
AssigneeValmet Corporation
InventorsMatti LePisto, Reijo Ilmanen, Markku Karlsson, Sauli Laakso
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AssigneeValmet Corporation
InventorsMatti LePisto, Reijo Ilmanen, Markku Karlsson, Sauli Laakso
Estimating the term…
A method for contact-free drying of a paper or board web or of any other corresponding continuous web. During drying, both infrared radiation and drying air jets are used. The web is carried by the air jets through the dryer free of contact. The moving web is first passed into an infrared drying gap, in which a drying energy pulse of relatively short duration is directed at the web, the power of the energy pulse being substantially higher than the average drying power of the dryer per unit of area. After the infrared drying gap, the web is immediately passed into an airborne web drying gap wherein the web is supported and dried by means of air jets. Air is brought into the infrared unit, which air having been heated in the infrared unit is passed as replacement air and/or drying air for the airborne web drying unit or units placed after the infrared unit. The air flows to be passed into the infrared unit are passed in connection with the inlet gap of the web to both sides of the web so as to form both accompanying and sealing air jet flows.
A method of contact-free drying a paper or board web (W) wherein both infrared radiation (R) and drying air jets are used for drying, said drying air jets carrying said web (W) free of contact as said web moves through said dryer, and wherein after said infrared drying step said web is substantially immediately moved into an airborne web-dryer wherein said web is supported by and dried with air jets, the method comprising:
Dependencies are inferred from the claim text.