JPH04357375A - Slide valve for high temperature - Google Patents

Abstract

PURPOSE:To keep a gap between a ceramic plate and valve body constant even if a fixing pin for fixing the ceramic plate to the valve body is subjected to thermal expansion. CONSTITUTION:A ceramic plate 14 is secured fixedly to a valve body 4 of a slide valve through a metal fixing pin 15. The fixing pin 15 is formed on the head 17 side with a tapered surface 18 converging downward, and the ceramic plate 14 is provided with a pin hole 20 having a tapered surface 21 receiving the same and removably abutting against the tapered surface 18 of the fixing pin 15. When the fixing pin 15 and ceramic plate 14 are subjected to thermal expansion, the tapered surface 18 and tapered surface 21 receiving the same are always subjected to the thermal expansion on the same straight line with a fixed slant angle. Thus, even if the fixing pin 15 and ceramic plate 14 are subjected to thermal expansion since the tapered surface 18 abuts against the tapered receiving surface 21 under the same condition as that at the normal temperature, a gap between the ceramic plate 14 and the valve body 4 is not expanded more than that in the normal temperature so as to be kept constant all the time.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-temperature slide valve used to control the flow rate of a fluidized chemical catalyst.

0002

2. Description of the Related Art Conventionally, in this type of high-temperature slide valve, the tip of the valve body is covered with a plurality of ceramic plates to suppress wear of this part. The ceramic plate is fixed to the metal base plate of the valve body by a metal fixing pin.

0003

[Problems to be Solved by the Invention] However, according to the above-mentioned conventional type, since the coefficient of thermal expansion of ceramic material is smaller than that of metal material, high-temperature fluid containing powder flows through the slide valve and the valve body When the temperature reached a high temperature, the fixing pin expanded thermally, and the gap between the ceramic plate and the surface of the base plate became wider than at room temperature, and powder particles entered these gaps.

[0004] After the high-temperature fluid has finished flowing, when the temperature of the valve body decreases and returns to normal temperature, the fixing pin contracts. As a result, the ceramic plate is pressed against the base plate and the gap between the ceramic plate and the base plate tends to narrow, causing large stress on the ceramic plate due to the powder particles that have entered the gap, causing problems such as damage to the ceramic plate. happened.

[0005] The present invention solves the above problem, and even if the fixing pin that fixes the ceramic plate to the valve body expands and contracts due to the thermal influence of high-temperature fluid, problems such as damage to the ceramic plate occur. The purpose of this invention is to provide a high-temperature slide valve that can prevent this.

[0006]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a valve box that forms a flow path for a high-temperature controlled fluid containing powder and granules, and a valve box that is slidably supported on the valve box. In the slide valve, the valve body is formed of a metal base plate, and the valve body moves in and out in a direction across the flow path inside the valve box to control the flow rate of the controlled fluid. The upstream plane and tip surface of the tip are covered with a plurality of ceramic plates, and metal fixing pins are provided to fix these ceramic plates to the base plate of the valve body. A pin hole having a tapered receiving surface that can freely come into contact with and separate from the tapered surface of the fixing pin is formed in the ceramic plate.

[0007]

[Operation] With the above configuration, the ceramic plate is fixed to the base plate of the valve body through the fixing pins inserted through the respective pin holes with the tapered surface of the fixing pin in contact with the tapered receiving surface of the pin hole. There is.

[0008] When the valve body becomes hot due to the controlled fluid, the fixing pin and the ceramic plate thermally expand in the axial and radial directions. At this time, the tapered surface of the fixing pin and the tapered receiving surface of the ceramic plate thermally expand on the same straight line while always maintaining a constant inclination angle. As a result, even if the fixed pin and ceramic plate expand thermally, the tapered surface remains in contact with the tapered receiving surface in the same state as at room temperature, so the gap between the ceramic plate and the base plate does not become wider than at room temperature. , the gap can always be kept constant.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the controlled fluid 1 is a high-temperature fluid containing powder and granules, and the valve box 2 of the slide valve 7 is the controlled fluid 1.
It forms a flow path. Also, a valve seat 3 is provided inside the valve box 2.
A valve element 4 that opens and closes a flow path (port) formed by the valve seat 3 is disposed downstream of the valve seat 3.

The valve body 4 is slidably supported on both sides by guides 5 provided on the valve body 2, and the valve body 4 is guided by the guides 5 and attached to the valve seat. Move in and out in a direction that crosses the flow path No. 3. Therefore, the flow rate of the controlled fluid 1 is controlled by moving the valve body 4 in and out. Further, the valve body 4 is formed of a base plate 8 made of heat-resistant steel. (See FIG. 3) A seat ring 6 that seals between the valve seat 3 and the valve body 4 is fixed to the valve seat 3 with bolts, and the seat ring 6 is in sliding contact with the valve body 4. A valve stem 9 inserted into the valve body 2 through the valve body cover (not shown) is connected to the base end of the valve body 4. The valve stem 9 is connected to the valve body cover (not shown). (not shown).

[0011]Furthermore, on the inner surface of the valve body 2, a hexagonal mesh 12 made of stainless steel is welded and fixed, and the mesh of the hexsteel 12 is filled with a wear-resistant lining material 13. ing.

As shown in FIG. 2, the upstream plane and tip surface of the tip of the valve body 4 are covered with a plurality of wear-resistant ceramic plates 14, and these ceramic plates 14 are covered with chips. It is made of silicon oxide, etc. Further, a hexteel 12 is welded and fixed to a portion of the valve body 4 that is not covered by the ceramic plate 14, and the mesh of the hexteel 12 is filled with a wear-resistant lining material 13.

As shown in FIGS. 3 and 4, the ceramic plate 14 is fixed to the base plate 8 of the valve body 4 via fixing pins 15 made of heat-resistant steel. This may be done by fixing each ceramic plate 14 in contact with the surface of the base plate 8, or by fixing it with a certain gap S provided between the ceramic plate 14 and the base plate 8. good.

The fixing pin 15 is composed of a body part 16 and a head part 17 having a larger diameter than the body part 16. It is formed. A pin hole 20 is formed in the ceramic plate 14, and the tapered surface 18 of the fixing pin 15 is inserted into the pin hole 20.
A tapered receiving surface 21 that can be brought into contact with and separated from the contact surface is formed on the contact surface. A pin holding hole 22 corresponding to the pin hole 20 of the ceramic plate 14 is formed on the surface of the base plate 8 .

The fixing pin 15 is fitted into the pin hole 20, the tapered surface 18 abuts the tapered receiving surface 21, and the body portion 16
is fitted into the pin holding hole 22. The tip of the body 16 of the fixing pin 15 is fixed to the base plate 8 by welding.

The tapered surface 18 of the fixing pin 15 is formed at an inclined angle α with respect to the surface of the base plate 8.
The apex of this tapered surface 18 coincides with the intersection P between the axis 23 of the fixing pin 15 and the surface of the base plate 8.

The operation of the above configuration will be explained below. The ceramic plate 14 is fixed to the base plate 8 of the valve body 4 via the fixing pin 15 inserted through the pin hole 20 with the tapered surface 18 in contact with the tapered receiving surface 21 .

When the valve body 4 becomes high temperature due to the controlled fluid 1, the fixing pin 15 and the ceramic plate 14
undergoes thermal expansion in the axial and radial directions. The relationship between the tapered surface 18 of the fixing pin 15 and the tapered receiving surface 21 of the ceramic plate 14 at this time will be explained below. As shown in Figure 4,
An arbitrary point A is taken on the tapered surface 18 of the fixing pin 15 at room temperature, and a point B is taken on the tapered receiving surface 21 of the ceramic plate 14, which corresponds to the above point A. From point P above to point A
and the axial distance to point B is H, and from point P to point A
and the radial distance to point B is D.

As shown in FIG. 5, as the fixing pin 15 thermally expands in the radial direction, point A moves in the radial direction by d1. Further, as the ceramic plate 14 thermally expands in the radial direction, the point B moves in the radial direction by d2. Simultaneously with the thermal expansion in the radial direction, the fixing pin 15 also thermally expands in the axial direction, so that point A moves in the axial direction by h1. Furthermore, the ceramic plate 14 also thermally expands in the axial direction, and the point B moves in the axial direction by h2.

[0020] As a result, the following relationship is established. That is, if the coefficient of thermal expansion of the fixing pin 15 is C1 and the coefficient of thermal expansion of the ceramic plate 14 is C2, then d1=C1·D h1=C1·H. As a result, h1/d1=
H/D=tanα. ...(1) Similarly, d
2=C2・D h2=C2・H. As a result, h2/d2=
H/D=tanα. ...(2) Above (1)
, (2), points A and B move due to thermal expansion, but are always located on the straight line L having the same inclination angle α as the tapered surface 18 and the tapered receiving surface 21. As a result, even if the fixing pin 15 and the ceramic plate 14 expand thermally,
The tapered surface 18 is in contact with the tapered receiving surface 21 in the same state as at room temperature, so the gap S between the ceramic plate 14 and the base plate 8 does not become wider than at room temperature.
The gap S can always be kept constant.

In the above embodiment, the body 16 of the fixing pin 15
The tip is fixed to the base plate 8 by welding, but this is done by forming threaded parts in the body 16 of the fixing pin 15 and the pin holding hole 22 of the base plate 8, and screwing the body 16 into the pin holding hole 22. It may be fixed.

[0022]

As described above, according to the present invention, the ceramic plate covering the valve body is fixed to the base plate via the metal fixing pin, and the ceramic plate is inclined downwardly toward the head side of the fixing pin. By forming a pin hole in the ceramic plate with a tapered receiving surface that can come into contact with and separate from the tapered surface of the fixing pin, the tapered surface of the fixing pin and the tapered receiving surface of the ceramic plate are always in contact with each other. Thermal expansion occurs in the same straight line while maintaining a constant angle of inclination.

[0023]Thus, even if the fixing pin and the ceramic plate expand thermally, the tapered surface remains in contact with the tapered receiving surface in the same state as at room temperature, so the gap between the ceramic plate and the base plate becomes wider than at room temperature. The gap can always be kept constant. Therefore, the powder particles that have entered the gap between the ceramic plate and the base plate do not generate large stress on the ceramic plate, and damage to the ceramic plate can be prevented.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of a slide valve in one embodiment of the present invention.

FIG. 2 is a perspective view of the valve body of the slide valve.

FIG. 3 is a longitudinal sectional view showing a ceramic plate fixed to a base plate via fixing pins in the same embodiment.

FIG. 4 is a longitudinal cross-sectional view for explaining the relationship between the tapered surface of the fixing pin and the tapered receiving surface of the ceramic plate in the same embodiment.

FIG. 5 is an explanatory diagram for explaining the relationship between the tapered surface of the fixing pin and the tapered receiving surface of the ceramic plate in the same embodiment.

[Explanation of symbols]

1 Controlled fluid 2 Valve box 4 Valve body 7 Slide valve 8 Base plate 14 Ceramic plate 15 Fixed pin 17 Head 18 Tapered surface 20 Pin hole 21 Taper receiving surface

Claims (1)

[Claims] Claim 1: A valve box that forms a flow path for a high-temperature controlled fluid containing powder and granules, and a valve box that is slidably supported by the valve box and that moves in and out in a direction that crosses the flow path inside the valve box. In the slide valve, the valve body is formed of a metal base plate, and the upstream plane and tip surface of the tip of the valve body are formed by a plurality of ceramic plates. metal fixing pins are provided to fix these ceramic plates to the base plate of the valve body, a tapered surface that slopes downwardly is formed on the head side of these fixing pins, and the fixing pins are covered with the ceramic plates. A slide valve for high temperature use, characterized in that a pin hole having a tapered receiving surface that can come into contact with and separate from the tapered surface of the valve is formed in the tapered surface of the valve.