Metso Paper Inc.

Valmet Technologies, Inc.

Vaahto Paper Technology Oy

Bellmer Vaahto Paper Machinery Oy

Erkka Nieminen

Samppa J Salminen

Veikko Kankaanpää

Veli-Matti Vainio

Pertti K Heikkilä

Harri Kronholm

Vesa Harju

Erkki Kärkkäinen

An injector for a flotation cell, comprising a feed channel for feeding a fiber suspension flow to the flotation cell, a flow distribution element for distributing the fiber suspension flow fed to the injector into partial flows, a mixing apparatus for mixing air with the fiber suspension flow, and at least one air input point for sucking air to be mixed with the fiber suspension flow into the injector. The feed channel, the flow distribution element and the mixing apparatus are in the injector arranged with respect to one another such that a flow direction of the fiber suspension flow in the feed channel is substantially opposite to a flow direction of the fiber suspension flow through the flow distribution element and the mixing apparatus.

Injector for flotation cell

An injector of a flotation cell, the injector comprising a feed pipe for feeding a fiber suspension flow into the flotation cell, a mixing apparatus for mixing air into the fiber suspension flow and at least one air feed connection arranged before the mixing apparatus for feeding air into the injector. The injector further comprises a nozzle section which is arranged before the mixing apparatus and comprises an aperture plate provided with apertures and nozzles fixed to the aperture plate substantially at the apertures after the aperture plate, there being open spaces between the nozzles. The air to be fed from the air feed connection is arranged to flow into the spaces between the nozzles and further into the mixing apparatus with the partial flows of the fiber suspension flow entering from the nozzles.

Flotation cell

A paper or board machine has a fabric () that is adapted mobile as well as rolls (') arranged to support the fabric (). The fabric () is tensioned by changing the position of one roll (&#x2032;) of the rolls (&#x2032;). Correspondingly, the fabric () is guided by changing the alignment of one roll (&#x2032;) of the said rolls (&#x2032;). Surprisingly the fabric () is both tensioned and guided by changing the alignment and position of only one and the same roll (&#x2032;). In addition, the wrap angle of the fabric () at this roll (&#x2032;) is set higher than 30&#xb0;.

Method, arrangement and equipment for tensioning and guiding a fabric in a paper or board machine

A method for making a screen cylinder is described in which screen wires are arranged on the inner surface of a support wire at certain intervals and attached by a weld from the outer surface of the support wire. In a preferred embodiment of the invention, the screen wires are arranged in mounting grooves provided on the inner surface of the support wire and welded by a welding method providing deep penetration so that the weld extends through the support wire from the outer surface of the hoop to the screen wire. In another embodiment, a welding groove is formed on the outer surface of the support wire and the weld is effected in the welding groove. The invention further relates to a screen cylinder manufactured by the method of the invention.

Method of making screen cylinder and screen cylinder

Growing community of inventors

Tampere, Finland

Erkka Nieminen