Abstract: The invention relates to a measuring roll for a fibre-web machine, which roll has a shell on whose surface a sensor is arranged, and which roll is coated with a coating layer proper. The roll comprises at least one protective coating layer placed under the coating layer proper and on top of the sensor in such a way that when the coating layer proper is replaced, the protective coating layer remains substantially on top of the sensor and the roll shell when the coating layer proper is removed. The invention also relates to a method for coating a measuring roll of a fibre-web machine and to a method for replacing a coating of a measuring roll of a fibre-web machine.

Abstract: A method and a roll for measuring a tension profile is provided. The roll has planted on its surface a spirally helical pressure-sensitive film sensor, such as an EMFi pressure-sensitive film sensor, which makes contact with a web obliquely and which, co-directionally with the web, has a measuring range which is substantially equal to or shorter than a web overlap angle when the roll is used for measuring a lateral tension profile of the web.

Abstract: A method and a roll for measuring a tension profile is provided. The roll has planted on its surface a spirally helical pressure gauge sensor, such as an EMFi pressure gauge sensor, which makes contact with a web obliquely and which, co-directionally with the web, has a measuring range which is substantially equal to or shorter than a web overlap angle when the roll is used for measuring a lateral tension profile of the web.

Abstract: A method and a device for tracking the position of the edge of a moving web (12), such as a fabric or a web of a paper machine, in which method a pressure-sensitive sensor element (14) is disposed in/onto the surface of the roll (10) guiding the web (12), which sensor element reacts to the pressure applied to it by the moving web (12) by producing an electric signal, on the basis of which it is possible to determine the exact position of the edge of the web (12) on the roll (10). The band-like sensor element (14) comprises one single sensor strip or several sensor strips (141 . . . 14n) disposed successively in the band.

Abstract: A web is passed over a surface (11) which is at least partly curved in the running direction of the web, which extends across the web in the cross direction, and which is placed at a distance from the web, in which connection an air cushion is formed between the moving web and the curved surface. The temperature and moisture of the web are measured indirectly by measuring the temperature and moisture of the air cushion by several detectors (41) which are in communication with openings (40) formed in the curved surface in spaced relationship with one another in the cross direction of the web.

Abstract: A method and a device for tracking the position of the edge of a moving web (12), such as a fabric or a web of a paper machine, in which method a pressure-sensitive sensor element (14) is disposed in/onto the surface of the roll (10) guiding the web (12), which sensor element reacts to the pressure applied to it by the moving web (12) by producing an electric signal, on the basis of which it is possible to determine the exact position of the edge of the web (12) on the roll (10). The band-like sensor element (14) comprises one single sensor strip or several sensor strips (141 . . . 14n) disposed successively in the band.