Abstract: A dryer section in a papermaking machine has two reversing rolls to form a pocket between each pair of dryers in a dryer tier. The first reversing roll is a vacuum roll and the second reversing roll is a grooved roll. A blow box is disposed between the two rolls, the blow box provides suction for the grooved roll and provides vacuum which restrains a web on the dryer fabric as it travels between the first and the second rolls. The blow box also provides a supply of make-up air which extends in a cross machine direction along the pocket formed by the two reversing rolls. The blow box also supports a pivoting foil which is positioned against the dryer fabric as it moves from a first dryer, towards the first reversing roll. The foil defines a region of low pressure which restrains the web as it travels between the first dryer and the first reversing roll.

Abstract: A dryer section in a papermaking machine has two reversing rolls to form a pocket between each pair of dryers in a dryer tier. The first reversing roll is a vacuum roll and the second reversing roll is a grooved roll. A blow box is disposed between the two rolls, the blow box provides suction for the grooved roll and provides vacuum which restrains a web on the dryer fabric as it travels between the first and the second rolls. The blow box also provides a supply of make-up air which extends in a cross machine direction along the pocket formed by the two reversing rolls. The blow box also supports a pivoting foil which is positioned against the dryer fabric as it moves from a first dryer, towards the first reversing roll. The foil defines a region of low pressure which restrains the web as it travels between the first dryer and the first reversing roll.

Abstract: A ventilator apparatus is disclosed for supplying air from a source of pressurized air between a dryer and a web supported by a felt extending around a roll of a single tier drying section. The apparatus includes a housing which is connected to the source of pressurized air. The housing defines a nozzle for directing a flow therethrough of a current of air. The flow is directed from the nozzle towards a diverging nip defined between the dryer and the web supported by the felt when the felt diverges away from the dryer prior to the felt extending around the roll. The arrangement is such that the flow of air compensates for an underpressure generated by the felt when diverging away from the dryer so that fluttering of the web is inhibited.

Abstract: A single tier dryer system has dryer rolls with a reversing roll positioned between each pair to transfer and wrap the dryer felt and paper web against the next dryer roll. A vacuum box is positioned between the dryer rolls and over the reversing roll to hold the web on the dryer felt by vacuum. Threading of a tail from the web is accomplished by blowing the web tail off a first dryer roll's surface with a jet of air positioned adjacent to the position on the dryer roll where the dryer felt leaves the dryer roll's surface. The vacuum box is divided by a baffle to isolate a portion of the vacuum box near the front of the dryer rolls, and a damper is positioned within the reversing roll to increase the vacuum in the isolated portion of the vacuum box to facilitate threading of the tail.