A blade segment (4, 8) for a refiner (1) for refining fibrous material has first (20) and second (21) end edges opposite one another in a direction of a longitudinal axis (LA) of the blade segment (4, 4a, 4b, 8, 8a, 8b), and first (22) and second (23) side edges which extend between the first end edge and the second end edge. The blade segment has a refining surface (5, 9) with blade bars (26) and grooves (27) therebetween on a front surface (25) of the blade segment (4, 8). At least one side edge (22, 23) has at least two edge portions (31, 33, 35, 41, 43, 45) arranged to deviate from the direction of the longitudinal axis (LA) of the blade segment (4, 4a, 4b, 8; 8a, 8b) and connected by an elbow (32, 34, 42, 44) between each two edge portions (31, 33, 35, 41, 43, 45).

A refiner for beating a raw material supplied between a stator beating part and a rotor beating part, and discharging the beaten raw material, the refiner including a rotating shaft, the rotor beating part attached to the rotating shaft, a motor configured to drive the rotating shaft; and a motor control part configured to variably control a rotation of the motor. The rotation of the motor of the rotor beating part is controlled by the motor control part to beat the raw material.

A refining member comprising a refining body with a refining surface comprising first and second refiner bars separated by first and second refiner grooves, respectively. The first refiner bars extend from a radially inward position to a first radially outward position. The second refiner bars extend to a second radially outward position that is nearer to an outermost part of the refining body than the first radially outward position. The second refiner bars have a longitudinal length from about 0.6 cm to about 10 cm. The first and second refiner bars have a respective first and second maximum height extending upward from a floor of a respective, adjacent first or second refiner groove. The second maximum height is at least 0.35 mm less than the first maximum height. The first refiner bars are adapted to refine wood fibers and the second refiner bars are adapted to break up fiber bundles.

A defibering and deflaking pulper has a defibering rotor-stator pair and a deflaking rotor-stator pair for processing a fiber-based material into smaller pieces. The defibering and deflaking pulper creates an impeller-produced vortical circulation that pulls the material through a defibering rotor-stator interface, where the material is broken down into smaller pieces, and then through a deflaking rotor-stator interface, where the smaller pieces are broken down into even smaller pieces. The defibering and deflaking pulper accumulates the defibered and deflaked material that passes through the defibering rotor-stator interface and the deflaking rotor-stator interface for further processing. This combination of defibering and deflaking in the defibering and deflaking pulper reduces plugging from larger pieces of the material and reduces downstream processing of the material, thus increasing productivity and reducing costs.

A measurement system for monitoring a gap adjustment mechanism of a processing device which has oppositely positioned processing elements with a gap between them. The measurement system has a first measuring device to measure information describing a position of that processing element which is moved by at least one actuating unit of the gap adjustment mechanism for adjusting the size of the gap, and at least one second measuring device to measure information describing a position of the at least one actuating unit. The measurement system has a data processing device configurable to determine the condition of the gap adjustment mechanism based on the information describing the position of the processing element and the information describing the position of the at least one actuating unit. Additionally, a method for monitoring a condition of a gap adjustment mechanism of a processing device.