Conditioning doctor blade for fiber web machine

Patent metadata

Field	Value
Publication number	US-10821679-B2
Application number	US-201816020789-A
Country	US
Kind code	B2
Filing date	Jun 27, 2018
Priority date	Jun 29, 2017
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

A conditioning doctor blade (11) for a fiber web machine contains a number of reinforcement fiber layers (24, 26) laminated on top of one another into an epoxy matrix (20), and silicon carbide particles (21), so that the reinforcement fiber layers (24, 26) have formed a fiber core (22) and surface fiber layers (23) on both sides of the fiber core (22). There is less epoxy matrix (20) in the fiber core (22) than in the surface fiber layers (23).

First claim

We claim:

1. A doctor blade for a fiber web machine comprising:
a fiber core having a cross-machine length, a machine direction width, a Z-direction thickness, a first side in the Z-direction and a second side opposite the first side in the Z direction, and is formed of at least two reinforcement fiber layers laminated on top of one another in a first epoxy matrix, each reinforcement fiber layer comprising a fiberglass mat with fibers predominantly extending in the machine direction, each said mat having exterior surfaces spaced in the Z direction, and wherein essentially all the exterior surfaces of the fiberglass mats are precoated with epoxy resin to form epoxy external surfaces outwardly of each mat exterior surface, and wherein at least a portion of each epoxy external surface has a selected amount of silicon carbide particles placed thereon, such that the amount, location, and a mixture ratio of the silicon carbide particles and epoxy resin exterior to each mat within each reinforcement layer is limited by the epoxy external surface;
a first side part having surface layer(s) of fiber in a second epoxy matrix, bonded to the fiber core first side, and a second side part having surface layer(s) of fiber in a third epoxy matrix, bonded to the fiber core second side; and
wherein the fiber core has a first epoxy matrix weight percentage, and the first side part has a second epoxy matrix weight percentage, and the second side part has a third epoxy matrix weight percentage, and wherein the first epoxy matrix weight percentage is less than the second epoxy matrix weight percentage and less than the third epoxy matrix weight percentage.

2. The doctor blade of claim 1 wherein the fiber core first epoxy matrix weight percentage is 10-25 percent less than the second epoxy matrix weight percentage, and the third epoxy matrix weight percentage.

3. The doctor blade of claim 2 wherein the fiber core first epoxy matrix weight percentage is 15-20 percent less than the second epoxy matrix weight percentage, and the third epoxy matrix weight percentage.

4. The doctor blade of claim 1 wherein the fiber core includes 2 to 5 fiberglass layers.

5. The doctor blade of claim 1 wherein the fiber core includes 2 to 4 fiberglass layers.

6. The doctor blade of claim 1 wherein the silicon carbide particles have a grain size of GRIT600.

7. The doctor blade of claim 1 wherein the first epoxy matrix weight percentage of the fiber core is 30-35 percent.

8. The doctor blade of claim 7 wherein the second epoxy matrix weight percentage, and the third epoxy matrix weight percentage are between 35-45 percent.

9. The doctor blade of claim 1 wherein the doctor blade is a pressed laminate.

10. The doctor blade of claim 1 wherein the first side part fiber layers and second side parts fiber layers include carbon fiber layer(s) of a grammage which is 15-25 percent smaller than that of the fiber layers of the fiber core.

11. The doctor blade of claim 1 wherein the thickness of the doctor blade in the Z direction is from one to two millimeters.

12. The doctor blade of claim 1 wherein the exterior surfaces of the fiberglass mats precoated with epoxy resin is essentially on an area of the fiberglass layer(s) defined by two times the length times the width of the fiber core.

13. A doctor blade for a fiber web machine comprising:
a plurality of reinforcement fiber layers laminated on top of one another into an epoxy matrix wherein reinforcement fibers predominantly extend in a machine direction;
wherein the plurality of reinforcement fiber layers form a first side part and a second side part with a core therebetween;
wherein the core has at least two epoxy matrix layers separated by reinforcement fibers in a matrix which predominantly extends in the machine direction;
wherein the at least two epoxy matrix layers are substantially composed of a mixture of epoxy matrix and silicon carbide particles; and
wherein the epoxy matrix of the core has a weight percentage of epoxy matrix that is 10-25 percent less than that of the first and second side parts.

14. The doctor blade of claim 13 wherein the core epoxy matrix weight percentage is 15-20 percent less than that of the first and second side parts.

15. The doctor blade of claim 13 wherein the fiber core includes 2 to 5 fiberglass layers, each layer separated by an epoxy matrix layer substantially composed of a mixture of epoxy matrix and silicon carbide particles.

Assignees

• Valmet Technologies Inc

Inventors

• Hulden Håkan
• Ruotsalainen Harri

Classifications

• D21G3/005 Primary

  Doctor knifes · CPC title

• B29C70/025 Primary

  with particular filler · CPC title