Static dewatering element for a web forming machine and a method for covering a static dewatering element designed for a web forming machine

1. A method for coating a static dewatering element for a web forming machine, comprising the steps of:

forming a hard wear resistant intermediate layer;

forming a surface layer on the intermediate layer which surface layer is less hard and less wear resistant, by thermally flame spraying the static dewatering element to form a coating with flame sprayable powder particles which are agglomerates, the agglomerates consisting essentially of: primary particles of an average size smaller than 0.5 μm, and a minimum size of 0.1 μm and a maximum size of 1.0 μm; and

grinding the less hard and less wear resistant surface layer.

2. The method of claim 1 wherein the coating is sealed using a sealant after forming the coating.

3. The method of claim 2 wherein the coating is ground after sealing.

4. The method of claim 3 further comprising re-covering the dewatering element after use.

5. A static device used for dewatering a web in a web forming machine, comprising:

a dewatering element having a frame layer composed of a material selected from the group consisting of: carbon composite material, glass fiber composite, stainless steel, and aluminum;

a bonding layer which is a thermally sprayed coating and bonded to the frame layer;

a center layer which is a thermally sprayed coating, the center layer overlying the bonding layer and bonded to the frame layer by the bonding layer;

a surface layer overlying the center layer and forming a surface which engages a fabric or felt in a web forming section or a press section of a web forming machine, the surface layer formed by a thermally sprayed coating, the surface layer being on top of the center layer and being composed of powder particles that are agglomerates consisting essentially of: primary particles of an average size of less than 0.5 μm, and a minimum size of 0.1 μm and a maximum size of 1.0 μm wherein the surface which engages a fabric or felt has a roughness smaller than 0.3 μm;

wherein the surface layer, the center layer and the bonding layer have a thickness of 10-1000 μm;

wherein the primary particles are 80-90% base material and 10-20% blend material; the base material being selected from the group consisting of: Cr 2 O 3 , TiO 2 , Al 2 O 3 , SiO 2 , ZrO 2 , and tungsten carbide; and the blend material being selected from the group consisting of: cobalt, chromium, nickel, boron and silicon;

wherein the surface layer is wear resistant but less hard and less wear resistant than the center layer, and wherein the bonding layer has a hardness between those of the surface layer and the center layer; and

wherein the dewatering element has portions forming openings which perforate the frame layer, the openings having medians which are at a first angle of 35° to 50° relative to a normal of the surface which engages a fabric or felt, and the first angle measured in the direction from which a fabric or felt comes as it moves over the surface which engages a fabric or felt and wherein the portions forming openings are treated with a surface energy reducing agent.

6. The dewatering element of claim 5 wherein the surface layer and the center layer are of different colors.