Refiner blade element

Patent metadata

Field	Value
Publication number	US-11891758-B2
Application number	US-202017004882-A
Country	US
Kind code	B2
Filing date	Aug 27, 2020
Priority date	Aug 28, 2019
Publication date	Feb 6, 2024
Grant date	Feb 6, 2024

Abstract

A blade element pair (20) for a refiner (1, 2, 3) is intended for refining fibrous material. Each blade element (5, 5′, 8, 8′) of the blade element pair (20) has a refining surface (6, 9) with blade bars (16, 18) and blade grooves (17, 19) extending along the blade element (5, 5′, 8, 8′), and openings (14,15) extending through the blade element (5, 5′, 8, 8′). The openings (14, 15) in one of the blade elements (5, 5′, 8, 8′) is at different axial (A) or radial (R) positions from the openings (14,15) in the other blade element (5, 5′, 8, 8′) when the blade elements (5, 5′, 8, 8′) of the blade element pair (20) are set substantially opposite to each other.

First claim

We claim:

1. A blade element pair for a refiner for refining fibrous material comprising:
at least one first blade element for mounting to the refiner to rotate about an axis defining an axial direction and a radial direction, the at least one first blade element having a first refining surface extending in at least one of the radial direction and the axial direction, the first refining surface having first blade bars and first blade grooves therebetween, the first blade bars and first grooves extending along the first blade element in at least one of the radial direction and the axial direction and wherein the at least one first blade element has first openings for the passage therethrough of material to be refined and which extend through the at least one first blade element in at least one of the radial direction and the axial direction, wherein the first openings have a first length in the axial direction;
at least one second blade element for mounting to the refiner, the at least one second blade element having a second refining surface extending in at least one of the radial direction and the axial direction, the second refining surface having second blade bars and second blade grooves therebetween and extending along the second blade element in at least one of the radial direction and the axial direction and wherein the at least one second blade element has second openings for the passage therethrough of material to be refined which extend through the second blade element in at least one of the radial direction and the axial direction, wherein the second openings have a second length in the axial direction which is greater than the first length;
wherein the at least one first blade element and the at least one second blade element when mounted to the refiner are set substantially opposed to each other in such a manner that the first and second refining surfaces are opposed such that a refiner chamber for receiving material to be refined is formed therebetween; and
wherein the first openings in the first blade element and the second openings in the second blade openings are arranged at different axial or radial positions such that material to be refined does not pass between the first openings and the second openings without engaging the first refining surface and the second refining surface.

2. The blade element pair of claim 1 wherein the first refining surface and the second refining surface each have at least one refining surface zone without openings and at least one refining surface zone with openings.

3. The blade element pair of claim 1 wherein the at least one first blade element has a first edge and a second edge between which the first refining surface extends, and wherein the at least one second blade element has a first edge and a second edge between which the second refining surface extends; and
wherein the first refining surface and the second refining surface each comprises a plurality of refining surface zones having openings extending through the blade element.

4. The blade element pair of claim 1 wherein at least one of the first blade element and the second blade element is comprised of a plurality of blade segments, each blade segment having a first and a second end edge and a first and a second side edge extending between the first and second end edges;
wherein at least one of the first and second openings cut out indents in at least one of the first and second side edges, the indents extending through a whole thickness of the blade segment and extending from the first side edge of the blade segment toward the opposite second side edge or vice versa.

5. The blade element pair of claim 1 wherein the first blade bars and first blade grooves define a first pitch comprising one of said first blade bars and one of said first blade grooves, wherein the first pitch is repeated to form the first refining surface and each first pitch is at most 3 mm wide in a direction transverse to the said one of said first blade bars and one of said first blade grooves; and
wherein the second blade bars and second blade grooves define a second pitch comprised of one of said second blade bars and one of said second blade grooves, wherein the second pitch is repeated to form the second refining surface and each second pitch is at most 3 mm wide in a direction transverse to the said one of said second blade bars and said one of said second grooves.

6. The blade element pair of claim 5 wherein the width of the first blade bars is at most half of the first pitch and wherein the width of the second blade bars is at most half of the second pitch.

7. The blade element pair of claim 6 wherein the first blade bars and the second blade have a height of at most 10 mm.

8. The blade element pair of claim 1 wherein the first blade bars of the first refining surface and the second blade bars of the second refining surface are crosswise to each other.

9. The blade element pair of claim 8 wherein an intersecting angle between the first blade bars and the second blade bars is from 10° to 100°.

10. The blade element pair of claim 1 wherein the first openings define a first total open area of the first blade element, and wherein the second openings define a second total open area of the second blade element and wherein the first open area is from 5% to 30% of a surface area of the first refining surface of the first blade element and the second open area is from 5% to 30% of a surface area of the second refining surface of the second blade element.

11. The blade element pair of claim 1 wherein the second length is greater than twice the first length.

12. The blade element pair of claim 1 wherein the first blade openings are circular and the second blade openings are elongated.

13. The blade element pair of claim 1 wherein there are more first blade openings than second blade openings.

14. A blade element pair for a refiner for refining fibrous material comprising:
at least one first blade element for mounting to the refiner to rotate about an axis defining an axial direction and a radial direction, the at least one first blade element having a first refining surface extending in at least one of the radial direction and the axial direction, the first refining surface having first blade bars and first blade grooves therebetween, the first blade bars and first grooves extending along the first blade element in at least one of the radial direction and the axial direction and wherein the at least one first blade element has first openings for the passage therethrough of material to be refined which extend through the at least one first blade element in at least one of the radial direction and the axial direction, wherein the first openings have a first length in the radial direction;
at least one second blade element for mounting to the refiner, the at least one second blade element having a second refining surface extending in at least one of the radial direction and the axial direction, the second refining surface having second blade bars and second blade grooves therebetween and extending along the second blade element in at least one of the radial direction and the axial direction and wherein the at least one second blade element has second openings for the passage therethrough of material to be refined which extend through the second blade element in at least one of the radial direction and the axial direction, wherein the second openings have a second length in the radial direction which is greater than the first length;
wherein the at least one first blade element and the at least one second blade element when mounted to the refiner are set substa

Assignees

• Valmet Technologies Oy

Inventors

• Huhtanen Juha-Pekka
• Loijas Marko

Classifications

• D21D1/22 Primary

  Jordans · CPC title

• D21D1/24 Primary

  Jordan rolls · CPC title

• D21D1/306 Primary

  Discs · CPC title

• D21D1/26

  Jordan bed plates · CPC title

• D21D1/303

  Double disc mills · CPC title