A blade element (11) for a refiner (10) for refining fibrous material has a blade element body (12) and blade bars (13, 13a, 13b) and blade grooves (14, 14a, 14b) therebetween. Bottoms of the blade grooves (14, 14a, 14b) have, in the longitudinal direction (LD) of the blade grooves, a variable depth profile comprising alternating high points (14a, 14b) and low points (14a, 14b) so that there is a phase shift (X2) between the high points (14a, 14b) and the low points (14a, 14b) of the variable depth profiles of the bottoms of the adjacent blade grooves (14a, 14b). Also, a refiner (10) for refining fibrous material and a method for manufacturing the blade element (11) for the refiner (1).

A blade element (11) for a refiner (10) for refining fibrous material has a blade element body (12) and blade bars (13, 13a, 13b) and blade grooves (14, 14a, 14b) therebetween. Bottoms of the blade grooves (14, 14a, 14b) have, in the longitudinal direction (LD) of the blade grooves, a variable depth profile comprising alternating high points (14a, 14b) and low points (14a, 14b) so that there is a phase shift (X2) between the high points (14a, 14b) and the low points (14a, 14b) of the variable depth profiles of the bottoms of the adjacent blade grooves (14a, 14b). Also, a refiner (10) for refining fibrous material and a method for manufacturing the blade element (11) for the refiner (1).

A powder gathering apparatus includes at least two rotating plates and a driving mechanism. The at least two rotating plates are disposed with respect to each other. Each of the rotating plates includes at least one spherical member. The at least one spherical member protrudes from the rotating plate. The driving mechanism drives at least one of the at least two rotating plates to move, such that the at least two rotating plates get close to or away from each other. The driving mechanism drives the at least two rotating plates to rotate.

A powder gathering apparatus includes at least two rotating plates and a driving mechanism. The at least two rotating plates are disposed with respect to each other. Each of the rotating plates includes at least one spherical member. The at least one spherical member protrudes from the rotating plate. The driving mechanism drives at least one of the at least two rotating plates to move, such that the at least two rotating plates get close to or away from each other. The driving mechanism drives the at least two rotating plates to rotate.

A light weight plate segment configured to be mounted on a disc of a disperser or refiner for comminuted cellulosic material including: a front face having disperser teeth or refining bars; a back face having a raised post surrounding a fastener attachment structure and a raised plate positioning section; side edges of the plate segment; and a radially outer edge and a radially inner edge extending between the side edges; wherein the back face lacks raised structures along the side edges.

A light weight plate segment configured to be mounted on a disc of a disperser or refiner for comminuted cellulosic material including: a front face having disperser teeth or refining bars; a back face having a raised post surrounding a fastener attachment structure and a raised plate positioning section; side edges of the plate segment; and a radially outer edge and a radially inner edge extending between the side edges; wherein the back face lacks raised structures along the side edges.

Disclosed is a three-stage millstone including an upper stone having a grain inlet and an inlet path, a middle stone disposed under the upper stone for causing grain, introduced through the inlet path, to move to an edge thereof and grinding the grain using compressive force between the upper and middle stones, a lower stone disposed under the middle stone for secondarily grinding the grain using compressive force between the middle and lower stones, the upper surface of the lower stone being wider than the lower surface of the middle stone and being inclined downward to allow the ground grain to inwardly move from the edge of the middle stone to the center of the lower stone, the lower stone having a grain outlet passage, a rotation device for enabling rotation of the middle stone, other than the upper and lower stones, and an actuator for rotating the middle stone.

Disclosed is a three-stage millstone including an upper stone having a grain inlet and an inlet path, a middle stone disposed under the upper stone for causing grain, introduced through the inlet path, to move to an edge thereof and grinding the grain using compressive force between the upper and middle stones, a lower stone disposed under the middle stone for secondarily grinding the grain using compressive force between the middle and lower stones, the upper surface of the lower stone being wider than the lower surface of the middle stone and being inclined downward to allow the ground grain to inwardly move from the edge of the middle stone to the center of the lower stone, the lower stone having a grain outlet passage, a rotation device for enabling rotation of the middle stone, other than the upper and lower stones, and an actuator for rotating the middle stone.

A reducing machine having an air cooled cutting discs is disclosed. The air cooled discs have cutting surfaces on both sides. The cutting surfaces have edges which are sharpened for cutting input material when the cutting surface is facing the cutting surface of the opposed disc. When the cutting surface of the stationary disc is facing the housing, the cutting surface acts as a heat sink to air cool the stationary disc and the mill assembly in general. Air inlets in the housing lid permit air to flow over the cooling surface of the stationary plate. Air inlets in the carrying plate permit the carrying plate to channel air flow over the rotating cooling surface. A damper restricts air flow over the air cooling surfaces to control the temperature of the reducing machine, such as during start up.

A reducing machine having an air cooled cutting discs is disclosed. The air cooled discs have cutting surfaces on both sides. The cutting surfaces have edges which are sharpened for cutting input material when the cutting surface is facing the cutting surface of the opposed disc. When the cutting surface of the stationary disc is facing the housing, the cutting surface acts as a heat sink to air cool the stationary disc and the mill assembly in general. Air inlets in the housing lid permit air to flow over the cooling surface of the stationary plate. Air inlets in the carrying plate permit the carrying plate to channel air flow over the rotating cooling surface. A damper restricts air flow over the air cooling surfaces to control the temperature of the reducing machine, such as during start up.