REDUCED MASS PLATES FOR REFINERS AND DISPERSERS

• US 20140339348A1
• Filed: 04/17/2014
• Published: 11/20/2014
• Est. Priority Date: 05/15/2013
• Status: Active Grant

• Current Assignee: Andritz Incorporated
• Original Assignee: Andritz Incorporated
• Inventors: Ihalainen, Ismo, Raymond, Yves, REHNSTROM, MIKAEL
• Granted Patent: US 10,166,546 B2
• Time in Patent Office: Days
• US Class Current: 241/298
• CPC Class Codes: B02C 7/02 with coaxial discs
• CPC Class Codes: B02C 7/12 Shape or construction of discs
• CPC Class Codes: B22D 31/002 Cleaning, working on castings
• CPC Class Codes: D21D 1/008 Discs
• CPC Class Codes: D21D 1/306 Discs
• CPC Class Codes: Y10T 29/49989 Followed by cutting or removing material

Abstract

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.

Claims

1. A plate segment configured to be mounted on a disc of a disperser or refiner of comminuted cellulosic material, the segment comprises:

a front face of a plate segment including disperser teeth or refining bars;

a back face of a plate segment on an opposing major surface to the front face, including a raised post surrounding a fastener attachment structure and a raised plate positioning section;

side edges of the plate segment located along edges of the front face and the back face; 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.

2. The plate segment in claim 1, wherein the back surface contains at least 20% less support material as compared to a conventional plate segment.

3. The plate segment in claim 1, wherein the raised post is aligned along a radial line extending from a rotational axis of the disperser or refiner.

4. The plate segment in claim 1 further comprising a second post and a second plate positioning section aligned along a radial line extending from a rotational axis of the disperser or refiner.

5. The plate segment in claim 1, wherein the radially outer edge is devoid of a raised structure.

6. The plate segment in claim 1, wherein the raised post and raised plate positioning section each have contact surfaces, and the contact surfaces are aligned in a common plane.

7. The plate segment in claim 1 further comprising a rib extending radially outward from the post to the plate positioning section.

8. An assembly of a disc and a plate segment for a refiner or disperser comprising:

a plate segment 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 located along edges of the front face and back face, 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; and

a disc having a disc mounting surface configured to mount the plate segment, the disc mounting surface abuts the post and plate positioning section of the plate segment.

9. The assembly of claim 8 further comprising plate segments mounted side by side on the disc mounting surface to form an annular array on the mounting surface of the disc, and the plate segments are not mounted to adjacent plate segments.

10. The assembly of claim 8 further comprising a spaced region between the plate segment back surface and the disc mounting surface in which the back surface do not abut the disc mounting surface except for a surface on the raised post and the raised plate positioning section that abut the disc mounting surface.

11. The assembly of claim 8 further comprising an annular ring on the disc mounting surface, wherein the annular ring is radially inward and adjacent to the radially inner edge of the plate segment.

12. The assembly of claim 8, wherein a surface of the radially inner edge of the plate segment faces a surface of the annular ring, and the surfaces are straight in a direction of an axis of a refiner or disperser.

13. The assembly of claim 12, wherein an annular space between the facing surfaces has a thickness in a range of 0.5 to 2.5 mm.

14. The assembly of claim 12 wherein a surface of the radially inner edge of the plate segment faces a surface of the annular ring, and the surfaces form an annular partial space to receive an annular seal.

15. The assembly of claim 12, wherein the surfaces abut at various points along the inner edge of the plate segment.

16. The assembly of claim 11, wherein a surface of the radially inner edge of the plate segment faces a surface of the annular ring, the surfaces each have a grooved space, and the grooved spaces form a track to receive an annular seal.

17. The assembly of claim 16, wherein the annular seal is a deformable seal.

18. The assembly of claim 8, wherein a surface of the radially inner edge of the plate segment faces a surface of the annular ring, and the surfaces are parallel to each other and oblique to a direction of an axis of a refiner or a disperser.

19. The assembly of claim 18, wherein the surface of the annular ring includes a lip extending underneath the plate segment.

20. The assembly of claim 18, wherein the inner ring has a thickness greater than the thickness of the plate segment at the radially inward edge, such that the radially inward edge does not abut the disc mounting surface.

21. The assembly of claim 16, wherein the annular seal is in a shape of circular, oval, rectangular, triangular, octagonal, or combinations thereof.

22. A plate segment comprising:

a front face on a plate segment, including disperser teeth or refining bars;

a back face on a major surface of the plate segment opposing the front face, including a raised post surrounding a fastener attachment structure and a raised plate positioning section;

side edges of the plate segment located along edges of the front face and the back face;

a radially outer edge and a radially inner edge extending between the side edges; and

a grooved space on the back face and adjacent to the radially inner edge, the grooved space is configured to receive a seal;

wherein the back face lacks raised structures along the side edges.

23. The plate segment of claim 22, wherein the radially inner edge of the back face is in a common plane with contact surfaces on the post and plate positioning section.

24. A method to form a plate segment comprising:

casting a plate segment by pouring molten metal into a mold, wherein the mold includes impressions for a back face of the plate segment that lacks raised ribs along sidewalls of the back face;

cooling the plate segment and removing the segment from the mold after pouring the molten metal;

cleaning and removing casting gates from the cooled plate segment; and

grinding the cooled plate segment.

25. The method of claim 24, wherein the grinding of the plate segment includes an automated robotic rough grinding step followed by a manual precision grinding step.

26. The method of claim 24, wherein the plate segment is configured for use in a refiner or a disperser.

27. The method of claim 24, wherein the depressions in the mold for the back face are limited to depressions for at least one fastener support post, at least one plate positioning section radially aligned with each fastener support post, and at least one rib extending between each aligned fastener support post and plate positioning section.