Abstract: The invention relates to a method and apparatus for measuring the viscosity of a medium with the aid of a blade (2) pivotally suspended such as to oscillate between two side walls (3, 4) in a measuring zone. The blade (2) is caused to pivot intermittently, with constant forces from an electromagnetic system (9) and a plunger coil (20), in the medium between the two fixed side walls (3, 4) which have a chief plane preferably extending parallel to, and in the same direction as the chief plane of the blade (2).

Abstract: The invention relates to a method and device for measuring and regulating the concentration, preferably of a fibre suspension, with the aid of a blade (1) pivotally suspended in the suspension. The blade (1) is caused to pivot such that its trailing end (8) moves between two end positions (A,B) in the suspension for providing a predetermined angular stroke (.alpha.). Time measurement is carried out when the trailing edge (8) of the blade (1) moves through its stroke from its upper end position (A) to its lower end position (B). The time obtained is a parabolic function of the concentration and varies in response to the shear force resistance in the fibre suspension of the blade (1) during its angular stroke, and thus in response to the concentration of solid substances in the suspension.

Abstract: The invention relates to an apparatus and a method for determining the drainability by permeability measurements. The apparatus is provided for taking a sample of a suspension, particularly a fibre suspension, e.g. such as flows in a pipe (2), said apparatus including a sampling piston housing (4) connected to the pipe (2) and accommodating a sampling piston (5) which can be displaced into the pipe (2) and has a through hole for forming a sample chamber (9) for taking out a pulp sample. The housing (4) is in communication with a dilution and mixing chamber (35) including an agitation or mixing device (36), the lower portion of the chamber (35) being closed off by an end member (23) with a screening plate (22).

Abstract: A method and a device for determining the lignin content in pulp by measuring the temperature increase on chlorination of a pulp sample with well-defined moisture content. The pulp sample is dewatered by pressing and simultaneously being blown through by a gas having low oxidization activity, subsequent to which the maximum temperature increase is registered when the pulp sample is blown through by chlorine gas.

Abstract: A screen device for separating undesirable impurities from a pulp suspension is provided with at least one continuous circular screen slot between a first chamber into which the suspension is conducted and from which undesirable material is removed and a second chamber from which the screen pulp suspension is transported. The slot is formed by two walls which are stationary in relation to each other and a cleaning device such as a doctor or knife bears against the screen slot, the cleaning device and slot being movable in relation to each other for continuous cleaning of the screen slot.