Shoe press operating method used during e.g. start=up of forming section containing shoe press, by rotating shoe roll at same speed as web or wire before closing to form nip

摘要

The web or forming wire (80) are guided through the gap in between the two rolls at a first speed and then the shoe roll is made to rotate at an equal speed before the two rolls are moved back together to form a nip. A method for operating a shoe press (10) comprising a cylindrical roll (22), a shoe roll, a displacement mechanism (33) for moving the cylindrical roll towards and away from the shoe roll, and a rotation mechanism for the shoe roll, includes the following steps : (i) the two rolls are separated to form a gap ; (ii) a fibrous web is guided through the gap at a first speed ; (iii) the shoe roll rotation mechanism is activated, the shoe roll peripheral rotation speed being essentially the same as the web speed ; and (iv) the displacement mechanism is activated to form a press nip between the two rolls. Independent claims are also included for (a) a start-up procedure for the forming section of a paper machine, using this method, and (b) the shoe press.