Valmet Paper Machinery Inc.

Valmet Oy

Raimo Rajala

Ilkka Jokioinen

Raimo Virta

Pertti Heikkila

Bertel Karlstedt

Reijo Ruottu

Sture Ahlskog

Jukka Parvinen

A device for contact-free supporting, turning, and spreading of a paper web, comprises a face (K) curved in accordance with the turning of the web (W), in connection with which face (K) the web (W) runs supported by air blown in between the face (K) and the web (W). The nozzle members in the device comprise guide faces (28a, 28b) and carrier faces (27, 37) placed in connection with the guide faces, air being blown through nozzle slots (26a,26b,36) in the nozzle members, transverse to the direction of running of the web (W), onto the carrier faces (27,37). The nozzle slots (26a,26b,36) are, from one side, defined by the guide faces (28,28b,38). The air-supported face (K) in the device is defined by carrier faces (27,37) substantially parallel to the run of the web (W) to be supported, provided at float-nozzle boxes (20) and at foil-nozzle boxes (30). In the direction of running of the web (W), the first nozzle box and the last nozzle box are float-nozzle boxes (20), in which the nozzles (26a,26b) that flow (F.sub.1) against each other produce pressurized carrier faces (K+). Between the float-nozzle boxes (20), there are one or several foil-nozzle boxes (30). Between the nozzle boxes (20,30), there are pressure equalization pockets (18).

Device for supporting, turning and spreading of a web

Apparatus for drying a moving web includes a first infrared dryer unit having a first infrared treatment gap, a gas-support unit situated substantially immediately after the first infrared dryer unit and having a gas-support unit gap into which web-supporting gas blowings are directed, and a second infrared dryer unit situated after the gas-support unit and having a second infrared treatment gap. The gas-support gap has a width which is less than the width of the first infrared gap and the width of the second infrared treatment gap is less than the width of the first infrared treatment gap and greater than the width of the gas-support gap. In accordance with the method, the web is passed through the first infrared treatment gap so that upon exiting from the gap, its temperature has preferably been raised only to a point where evaporation of water from the web is imminent but has not begun, whereupon the web is passed through the gas-support gap in which web-supporting gas blowings, preferably heated, are directed in regions of both sides of the web, whereupon the web is passed through the second infrared treatment gap where evaporative drying is accomplished.

Method and apparatus for drying a moving web

Method and Apparatus for Measuring Permeability to Air of a Wall-Like or Sheet-Like Element, comprising the use of a measurement head including a blower having an air-discharge nozzle, a blade wheel and a variable-speed motor for rotating the wheel to produce an air flow which discharges through the nozzle. Pressure in the blower and speed of blade wheel rotation are detected, with appropriate signals indicative thereof being input to a central unit which then appropriately adjusts speed of rotation of the blade wheel to correspond to a predetermined blower pressure value. Permeability value of the element is then determined at the central unit, based on relationship between the speed measurement signal values, and corresponding permeability values.

Method and apparatus for measuring air permeability of a wall-like or

Growing community of inventors

Kaarina, Finland

Raimo Rajala