JPS633804Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to improvements in erosion-resistant members such as blower blades, pipes and parts for transferring slurry or powder, heat exchanger tubes for boilers, etc. against erosion caused by solid particles in gas or liquid.

FIG. 1 is a schematic external view showing a part of a conventional blade of a blower, and FIG. 2 is an enlarged sectional view taken from A to A in FIG. 1.
In FIG. 2, 1 is the blade body, 2 is the stellite coating, 3 is the solid particle, 4 is an arrow indicating the direction of movement of the solid particle 3, and 5 is a location where erosion is likely to occur on the surface of the blade material.

As a conventional example, in order to provide erosion resistance, a stellite film 2 was applied to the surface of the blade body 1 by welding overlay or metal spraying with stellite, etc., as shown in Figure 2. In some places, abnormal erosion occurs due to the difference in the collision angle of the solid particles 3, so the effect against erosion was not sufficient.

When erosion occurs due to solid particles, the collision angle of the particles on the surface of the member is one of the important factors that affects the erosion. As shown in FIG. 3, it is well known that the manner in which erosion occurs is different between a hard and brittle brittle material 20 and a stretchable ductile material 21.

Therefore, as shown in FIG. 4, two types of materials having different characteristics against erosion are applied to the coating 20 at a location considered to be most effective depending on the collision angles 61 and 62 of the solid particles 3. , 21 could be provided separately to provide erosion resistance, but it is not possible to predict the collision angles 61, 62 of the solid particles 3 in advance and set the installation locations of the coatings 20, 21. It was difficult.

The present invention was proposed to eliminate the above-mentioned conventional drawbacks, and provides highly reliable erosion resistance by coating the surface of a metal member with a layer of a ductile material film and a brittle material film. It is an object of the present invention to provide an erosion-resistant member that is capable of resistant to erosion.

The embodiment of the present invention will be explained below with reference to the drawings. Fig. 5 is a cross-sectional view of a blade coated with a coating showing an embodiment of the present invention, and Fig. 6 is a cross-sectional view of the blade after use for a certain period of time. It is.

In the figure, 1 is a blade body, 20 is a coating made of a brittle material, and 21 is a coating made of a ductile material. Now, when applying an erosion-resistant coating to the wing body 1,
First, a coating 21 is formed on the first layer using a ductile material such as stellite by welding overlay or metal spraying.

Next, after thermal spraying a brittle material such as ceramic material onto the coating 21, the blade is heated in a heating furnace or heated from the surface with a gas heater to bring the ceramic coating to the desired temperature. The film 20 is formed by firing.

Next, to explain the effect, as a result of constant use of the blade material formed as described above, as shown by the dashed line 8 in FIG. The particles fall off due to high-angle collisions, and a coating 21 of a ductile material that is strong against high-angle collisions is exposed below. Further, in the remaining low-angle collision portions, the coating 20 of a brittle material that is strong against low-angle collisions remains as is.

As explained in detail above, the erosion-resistant member according to the present invention is coated with a layered film that can withstand high-angle and low-angle collisions of particles, so it has high reliability in erosion resistance and has a long service life of the member. is significantly improved.

In the above embodiment, after forming the film 21 of a ductile material on the surface of the blade body 1, the surface of the film 21 was laminated and coated with the film 20 of a brittle material. After coating with the film 20 of a brittle material, the surface of the film 20 may be formed with a film 21 of a ductile material. Moreover, these films 20, 2
1 can also be laminated in multiple layers.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a part of a conventional blade of a blower;
Figure 2 is an enlarged sectional view from A to A in Figure 1, Figure 3 A,
B is an explanatory diagram showing the relationship between the particle collision angle (α°) and the degree of erosion due to differences in coating materials, FIG. 4 is a cross-sectional view of another conventional blade, and FIG. 5 is a blade showing an embodiment of the present invention. FIG. 6 is a cross-sectional view illustrating the state of the blade shown in FIG. 5 after it has been used for a certain period of time. Explanation of the main parts of the figure, 1... wing body, 20...
Film made of brittle material, 21... Film made of ductile material.

Claims (1)

[Scope of utility model registration request] An erosion-resistant member characterized in that the surface of the metal member is laminated and coated with a film of a ductile material and a film of a brittle material.