Refiner and method for refining fibrous material

A method for refining fibrous material comprising the steps of:

• supplying fibrous material through a fiber inlet to a refiner in which at least one first refining body comprising first blade bars and first blade grooves between the first blade bars, and at least one second refining body comprising second blade bars and second blade grooves between the second blade bars, are arranged at least partly substantially opposite to one another to form a refiner chamber therebetween in which the fibrous material is refined, the refining chamber defining a refining area, wherein the fiber inlet is in supplying relation to the refiner chamber, and a refiner outlet is in receiving relation to the refiner chamber;
• wherein the blade bars of each refining body have portions most distant from the first or second refining body respectively, defining blade bar ends where refining of fibrous material takes place, and wherein the blade grooves have portions which extend to the blade bar ends;
• moving at least one of the first refining body and the second refining body relative to the other of the first refining body and the second refining body to refine fibrous material supplied to the refining chamber through the fiber inlet;
• feeding the fibrous material into or discharging the fibrous material from the refiner chamber through first elongated openings defined by portions of the first refining body, each first elongated opening extending to a first refining surface;
• wherein the first refining surface is defined as a surface which contains the blade bar ends of the first blade bars;
• the first elongated openings in the first refining body extending to the first refining surface through the first refining body and cutting through at least one first blade bar which crosses said first elongated opening such that each first elongated opening crosses said at least one first blade bar to split said first blade bar into two aligned but not continuous bar segments;
• feeding fibrous material directly from the first elongated openings between the refiner chamber and the fiber inlet or the fiber outlet;
• and
• which first elongated openings are angled transverse to the blade bars and blade grooves of the first refining body.

A blade segment for a refiner intended for refining fibrous material the refiner having a source of fibers supplying a fiber inlet, and a fiber outlet, wherein a plurality of abutting refiner blade segments is required to form a complete refiner surface;

• the blade segment comprising:
• wherein the blade segment has a refining surface portion;
• wherein the blade segment comprises blade bars having portions defining blade bar ends at the refining surface portion where refining of fibrous material takes place, and wherein blade grooves are defined between the blade bars and which blade grooves have portions which extend to the blade bar ends;
• wherein the refining surface portion of the blade segment has portions defining elongated openings through the blade segment each elongated extending to the refining through the refining segment and cutting through at least one blade bar which crosses said elongated opening such that each elongated opening crosses said at least one blade bar to split said blade bar into two aligned but not continuous bar segments;
• wherein the elongated openings communicate directly between the refining surface portion and the fiber inlet or the fiber outlet;
• and
• wherein the elongated openings through the blade segment are arranged at an angle transverse to the blade bars and blade grooves of the blade segment, the openings forming fibrous material supply openings, through which fibrous material to be refined can be fed into or discharged from the refining surface portion.