JPH08254199A - Mounting structure of wear resisting piece - Google Patents

Abstract

PURPOSE: To make wear of the downstream part of a wear resisting piece smaller than that of the top part thereof, prevent wear of a stud pin, and to provide an increased life for the downstream wear resisting piece. CONSTITUTION: A wear resisting piece 11 is attached on a surface 2 to be worn in such a manner that a slope 11a formed from a front 11c, facing the flow of fluid, to a top part 11b and scattering a flow in the direction of the top part 11b is provided, a stud pin 12 has a head part located in a level lower than that of the top part 11b and in a spot situated downstream from the top part 11b of the wear resisting piece 11 with which a surface 2 to be worn is covered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary fluid machine that handles fluids that induce erosion, such as a gas recirculation fan for a coal-fired boiler and a smoke exhaust fan for a sintering furnace, and a medium that induces erosion at a high flow rate. The present invention relates to a wear-resistant piece mounting structure applied to pipes, ducts, casings, and the like.

[0002]

2. Description of the Related Art FIG. 3 is an explanatory view of a conventional wear-resistant piece mounting structure which is installed on a blade of a gas recirculation fan (GRF) of a coal-fired boiler. In the figure, a conventional wear-resistant piece attachment structure is such that a liner 4 is attached to the front surface of a blade 2 fixed to a rotor 1 of a gas recirculation fan by a bolt 3, and a cross section formed on the surface of the liner 4 is trapezoidal. The wear-resistant pieces 6 made of ceramics having a trapezoidal cross section are inserted into the plurality of dovetail grooves 5 in contact with each other, and the movements of the wear-resistant pieces 6 made of ceramics are moved by the springs 7 in the axial direction of the dovetail grooves 5. In addition to the limitation, the wear resistant piece 6 made of ceramics is pressed against the dovetail groove 5 by the spring 8 to absorb the movement. Reference numeral 2a in the drawing is a main plate which is provided on the left and right of the blade 2 and supports the blade 2.

[0003]

As described above, in the conventional wear-resistant piece attachment structure, the trapezoidal ceramic wear-resistant piece 6 is attached through the liner 4, so that the component parts are formed. There are many points and types, and it requires a great deal of cost to manufacture and assemble them. Further, even if a part of the wear-resistant piece 6 is damaged, it is necessary to once release all the wear-resistant pieces 6 embedded in the dovetail groove 5 and reassemble them, which requires a great deal of time for maintenance. I need it. Instead of such a complicated wear resistant piece mounting structure,
If the ceramics wear-resistant piece of rectangular parallelepiped is directly attached to the front surface of the blade 2 by the stud welding pin, the erosion medium flows on the surface of the wear-resistant piece made of ceramic and wears the stud welding pin as well. Since the effect of fixing the wear resistant piece is lost, reliability is poor, and it cannot be used for important equipment, equipment having a large amount of fluid that induces erosion, and the like.

[0004]

SUMMARY OF THE INVENTION The wear-resistant piece mounting structure according to the present invention is intended to solve the above-mentioned problems, and is formed from the front surface facing the flow of fluid to the top, and scatters the flow toward the top. A wear-resistant piece having an inclined surface and covering the wear-resistant surface, and a stud for mounting the wear-resistant piece on the wear-resistant surface by mounting a head on the downstream side of the wear-resistant piece with the head lower than the top. It is characterized by a configuration including a pin.

[0005]

That is, in the wear-resistant piece mounting structure according to the present invention, the wear-resistant piece having an inclined surface formed from the front surface facing the flow of the fluid to the top and scattering the flow toward the top, covers the wear surface. A stud pin is attached to the downstream side of the top of the piece so that the head is lower than the top so that the wear-resistant piece is attached to the surface to be worn, and the fluid that induces erosion is formed on the front surface of the wear-resistant piece. By colliding with the inclined surface and scattering toward the top, the wear downstream of the top is reduced.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view of a wear resistant piece mounting structure according to an embodiment of the present invention, and FIG. 2 is an explanatory view of a wear resistant piece mounting structure according to another embodiment of the present invention. In the drawings, the mounting structure of the wear-resistant piece according to these examples is, for example, a gas recirculation fan of a coal-fired boiler, a smoke exhaust fan of a sintering furnace, a rotary fluid machine that handles fluids that induce erosion, or a medium that induces erosion. Pipes, ducts,
Used for casings, etc., wear-resistant pieces 11 made of ceramics or cemented carbide for improving wear resistance are attached by stud welding to the easily worn surface of the flow path. In such a case, it is important to prevent the stud itself from wearing.

In FIG. 1, the wear-resistant piece mounting structure is constructed on the blades of a gas recirculation fan (GRF) of a coal-fired boiler, and is shown in the figure instead of the conventional complicated wear-resistant piece mounting structure. As described above, a plurality of wear-resistant pieces 11 made of ceramics are directly attached to the front surface of the blade 2 by the respective stud welding pins 12. The wear-resistant piece 11 made of ceramics has a gentle slope 1 so that the fluid that induces erosion is scattered in the upward direction of the wear-resistant piece 11.
1a is provided from the front surface 11c of the wear-resistant piece 11 to the top portion 11b, and the stud welding pin 12 is attached at a position slightly deviated from the top portion 11b to the downstream side so that its head is lower than the top portion 11b. Is difficult to enter. In addition,
Although the strength of the wear-resistant piece 11 is low, as shown in FIG. 2, the shape of the wear-resistant piece 11 has an inclined surface 11a at the upper portion of the front surface 11c, and the portion for mounting the stud welding pin 12 is cut out into an L-shape to form the stud. The welding pin 12 may have a shape such that the head portion of the welding pin 12 is lower than the height h of the wear-resistant piece 11 in the cutout portion.

In this way, it is difficult for the fluid that induces erosion to flow to the head of the stud welding pin 12, and the stud welding pin 12 is protected by forming a barrier with the wear-resistant piece 11 made of ceramics. As a result, the fluid that induces erosion is a wear-resistant piece 11 made of ceramic.
The fluid that collides with the upward slope of the inclined surface 11a above the front surface 11c and scatters upward and flows the erosion-induced fluid to the head of the stud welding pin 12 after reaching the head of the stud welding pin 12 Does not wear. Further, as the flow goes downstream, the flow velocity also decreases and wear decreases.

In the conventional wear-resistant piece mounting structure, since the trapezoidal ceramic wear-resistant piece is mounted via the liner, the number and types of the components are large, and the manufacture and assembly thereof are difficult. It costs a lot of money. Even if a part of the wear-resistant piece is damaged, all the wear-resistant pieces embedded in the dovetail groove need to be released and reassembled, which requires a lot of time for maintenance. There is. If instead of such a complicated wear-resistant piece mounting structure, the wear resistance piece made of ceramics in the shape of a rectangular parallelepiped is directly attached to the front surface of the blade by the stud welding pin, the erosion medium will not wear out. Since the stud welding pin is worn while flowing on the surface of the piece and the effect of fixing the wear-resistant piece is lost, reliability is poor and it cannot be used for important equipment or equipment with a large amount of fluid that induces erosion. However, in the present mounting structure, the wear-resistant piece 11 has a gentle inclined surface 11a that scatters the fluid that induces erosion from the front surface 11c to the top 11b of the upper part to the wear-resistant piece 11 in the upward direction. The head of the stud welding pin 12 is located at the point where the hole for the stud welding pin 12 is slightly shifted downstream from the top 11b. The wall of the wear-resistant piece 11 made of ceramics having excellent wear resistance is formed on the upstream side of the stud welding pin 12 so as to prevent the fluid from entering, and functions as a protection wall against wear of the stud pin 12. Each of the wear-resistant pieces 11 is directly welded to the front surface of the blade 2 by the stud welding pin 12 so as to prevent erosion on the surface of the blade 2. As a result, liners, bolts, and
No springs are required, the number of parts is reduced, material cost,
Machining cost and installation man-hours are reduced. Further, when repairing the wear-resistant piece 11, it is not necessary to once release all the wear-resistant pieces assembled in the same dovetail groove and restore them again, and the repair cost is reduced. Further, the stud welding pin 12 is less worn and the reliability is improved, and the life of the downstream wear-resistant piece 11 is extended by scattering the fluid that induces erosion in the direction away from the surface of the blade 2.

[0010]

The mounting structure for the wear resistant piece according to the present invention is constructed as described above, and the wear on the downstream side of the top of the wear resistant piece is reduced, so that the stud pin does not wear and the wear resistant on the downstream side. The life of the piece is extended.

[Brief description of drawings]

FIG. 1 (a) is a front view of a wear-resistant piece mounting structure according to an embodiment of the present invention, FIG. 1 (b) is a perspective view of part B in FIG. 1 (a), and FIG. 1 (c). Is an explanatory diagram of the wear resistant piece installation,
FIG. 6D is an explanatory diagram of its operation.

FIG. 2 is a front view of a wear-resistant piece mounting structure according to another embodiment of the present invention.

FIG. 3 is a perspective view of a conventional wear-resistant piece attachment structure.

4 (a) is a sectional view taken along line AA in FIG.
3B is a perspective view of the wear-resistant piece, and FIG.
FIG. 9 is a cross-sectional view taken along the line CC in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotor 2 blade 11 wear-resistant piece 11a inclined surface 11b top part 11c front surface 12 stud welding pin

Claims (1)

[Claims] 1. A wear-resistant piece having an inclined surface formed from a front surface facing a fluid flow to a top portion to scatter the flow toward the top portion, and covering the wear-resistant surface; A wear resistant piece mounting structure comprising: a stud pin for mounting the wear resistant piece on the surface to be worn, the head being mounted lower than the top on the downstream side.