Abstract: A method of producing a corrugated product comprises the steps of providing at least one medium conditioning apparatus upstream of at least one of a corrugating labyrinth, single-facer, and/or double-backer. The moisture content in at least one of a web of medium material, first face-sheet, and/or second face-sheet is adjusted to be in the range of 6-9 wt. % moisture by applying a substantially continuous thin film of liquid thereto using the at least one medium conditioning apparatus. In one example, at least one heating arrangement is arranged downstream from the at least one medium conditioning apparatus to heat at least one of the web of medium material, first-face sheet, and/or second face-sheet.

Abstract: A method is provided for applying adhesive to the flutes of a corrugated sheet to bond a face surface thereto. An applicator roll is provided with a uniform thin coating of adhesive by a metering rod urged toward the surface of the applicator roll. A rider roll is provided adjacent the applicator roll and at the same height to form a vertical space for passage of the corrugated sheet therebetween so that the amount of glue applied to the crests of the flutes is proportional to the speed of the applicator roll. The space between the applicator roll and the rider roll is precisely controlled to control the degree of compression of the flutes during the application of the adhesive thereto. The flutes are preferably compressed 3-30, preferably 5-15, percent of their initial height to prevent application of adhesive to the rear sloping faces of the flutes.