Blade and creping arrangement

Patent metadata

Field	Value
Publication number	US-12128647-B2
Application number	US-202218683560-A
Country	US
Kind code	B2
Filing date	Jul 26, 2022
Priority date	Aug 16, 2021
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

A blade for creping a paper web from a dryer cylinder surface. The blade has a leading side and a front bevel surface to be impacted by the paper web. The leading side and the front bevel surface meet at a contact edge to contact the dryer cylinder. The front bevel surface has a 3D areal roughness, measured according to ISO 25178, of Sa>0.7 μm and/or Sz>18 μm and/or Sq>1.0 μm.

First claim

The invention claimed is:

1. A blade for creping a paper web from a dryer cylinder surface, the blade comprising:
a blade body having a leading side and a front bevel surface;
said leading side and said front bevel surface meeting at a contact edge;
said contact edge being configured to contact the dryer cylinder;
said front bevel surface extending at least 150 μm from said contact edge in a thickness direction of the blade and to be impacted by the paper web; and
said front bevel surface having a 3D areal roughness, measured according to ISO 25178, with at least one of:
Sa>0.7 μm, or
Sz>18 μm, or
Sq>1.0 μm.

2. The blade according to claim 1 , wherein portions or all of said front bevel surface have a 3D areal roughness, measured according to ISO 25178, of at least one of:
Sa between 0.7 μm and 9 μm; or
Sz between 18 μm and 100 μm; or
Sq between 1.0 μm an 11 μm.

3. The blade according to claim 1 , wherein a bevel angle β between said leading side and said front bevel surface lies between 60° and 110°.

4. The blade according to claim 3 , wherein the bevel angle ß lies between 70° and 95°.

5. The blade according to claim 1 , wherein a macroscopic shape of said front bevel surface is flat or has a macroscopic topography.

6. The blade according to claim 1 , wherein said front bevel surface has an undulatory topography.

7. The blade according to claim 1 , wherein said front bevel surface extends at least 250 μm from said contact edge, over an entire top side of the blade.

8. The blade according to claim 7 , wherein said front bevel surface extends at least 350 μm from said contact edge, over the entire top side of the blade.

9. The blade according to claim 1 , being a steel blade having a Vickers hardness in a range of 350 HV to 600 HV.

10. The blade according to claim 9 , further comprising a deposit of a wear-resistant material.

11. The blade according to claim 10 , wherein said wear-resistant material is a ceramic based material comprising at least one of a metal oxide, a metal carbide, a metal nitride, or combinations thereof.

12. The blade according to claim 11 , wherein said ceramic based material is a composite comprising particles of least a metal oxide, a metal carbide or a metal nitride distributed in a metallic matrix material.

13. The blade according to claim 10 , wherein said deposit has a Vickers hardness in a range from 900 to 1700 HV.

14. The blade according to claim 1 , wherein at least portions of said leading side have a roughness of Ra<0.4 μm and Rz<4.0 μm.

15. The blade according to claim 1 , having a thickness in an x-direction between 600 μm and 1500 μm.

16. A creping arrangement, comprising:
a dryer cylinder; and
a blade according to claim 1 for creping a paper web from a surface of said dryer cylinder.

17. The creping arrangement according to claim 16 , wherein a contact angle α between said blade and said dryer cylinder lies between 5° and 35°.

18. The creping arrangement according to claim 17 , wherein the contact angle α lies between 15° and 25°.

19. The creping arrangement according to claim 16 , wherein a pocket angle δ between a tangent to said dryer cylinder at said blade tip contact and said front bevel surface lies between 115° and 35°.

20. The creping arrangement according to claim 19 , wherein the pocket angle δ lies between 85° and 70.

Assignees

• Voith Patent Gmbh

Inventors

• Claudon Alexandre
• Pfirter Pierre-Yves

Classifications

• D21G3/04

  for drying cylinders · CPC title

• D21G3/005

  Doctor knifes · CPC title

• B31F1/145 Primary

  Blade constructions · CPC title