Dewatering member with a composite body for a paper or board machine and method for manufacturing a dewatering member with a composite body for a paper or board machine
View Patent ↗A dewatering member for a paper or board machine has a composite body ( 13 ) and a hard surface layer ( 12 ). The composite body ( 13 ) is manufactured in a pultrusion process. An adhesion layer ( 11 ) is formed on desired outer surfaces of the composite body ( 13 ) such that reinforcements passed to the adhesion layer ( 11 ) have been passed to the pultrusion process through a separate resin bath, to which an adhesion improving agent has been added such that the hard surface layer ( 12 ) can be applied directly onto it, and reinforcements forming the inner portion of the composite body ( 13 ) have been passed to the pultrusion process through a second resin bath. The composite body ( 13 ) is coated with a hard coating layer ( 12 ) produced by thermal spraying, and the coating ( 12 ) is ground.
1. A dewatering member for a paper or board machine, comprising:
an integrally formed pultruded composite body having an inner portion and an outer portion, wherein the outer portion is continuous with the inner portion, and wherein both the inner portion and the outer portion have parallel extending reinforcement fibers within resin, and wherein the outer portion has an adhesion improving agent locked into said reinforcement fiber-resin structure; and
a uniform hard surface layer adhered to the outer portion of the composite body.
2. The dewatering member of claim 1 wherein the inner portion of the composite body does not contain the adhesion improving agent.
3. The dewatering member of claim 1 wherein the hard surface layer is a thermally sprayed coating of nickel-chromium.
4. The dewatering member of claim 3 further comprising a further layer of thermally sprayed ceramic on the nickel-chromium layer.
5. The dewatering member of claim 3 further comprising a further layer of metal.
6. The dewatering member of claim 1 , wherein the adhesion improving agent is a metal powder.
7. The dewatering member of claim 6 , wherein the metal powder comprises nickel-chromium.
8. The dewatering member of claim 6 wherein the metal powder is over 50 wt. % of the portion of the resin quantity of the outer portion.
9. The dewatering member of claim 1 , wherein the hard surface layer is a thermal sprayed layer.
10. The dewatering member of claim 1 wherein the outer portion of the composite body has a thickness of at least 1 mm.
11. A dewatering member for a paper or board machine, comprising:
an integrally formed pultruded composite body having an inner portion and an outer portion, wherein the outer portion is continuous with the inner portion, and wherein both the inner portion and the outer portion have parallel extending reinforcement fibers within resin, wherein the outer portion has an adhesion improving filler locked into said reinforcement fiber-resin structure, and the inner portion resin does not contain any filler; and
a uniform hard surface layer adhered to the outer portion of the composite body.
12. The dewatering member of claim 11 wherein the hard surface layer is a thermally sprayed coating of nickel-chromium.
13. The dewatering member of claim 12 further comprising a further layer of thermally sprayed ceramic on the nickel-chromium layer.
14. The dewatering member of claim 12 further comprising a further layer of metal.
15. The dewatering member of claim 11 , wherein the adhesion improving filler comprises a nickel-chromium or tungsten powder.
16. The dewatering member of claim 11 wherein the outer portion of the pultrusion structure has a thickness of at least 1 mm.
17. The dewatering member of claim 11 wherein the adhesion improving filler is over 50 wt. % the portion of the resin quantity of the composite body outer portion.