JPH04362378A - Slide valve for high temperature - Google Patents

Abstract

PURPOSE:To prevent the generation of a gap between the adjacent faces of ceramic plates covering the valve body of a slide valve at the time of the valve body being thermally expanded by a high temperature fluid. CONSTITUTION:The respective adjacent faces of the first and the second ceramic plates 14A, 14B provided at a valve body 4 are formed into the first and the second inclined faces 15A, 15B. When the distance between the end face 11 and a ceramic pin 17 for connecting the first ceramic plate 14A to the valve body 4 is made L1, and the distance between the upstream side plane 10 and a ceramic pin 17 for connecting the second ceramic plate 14B to the valve body 4 is made L2, the inclination theta of the first and second inclined faces is set to be theta=tan<-1> (L2/L1). When the valve body 4 is thermally expanded, the optional points on the first and second inclined faces respectively move onto the same straight line of the inclination 6. Accordingly, even if the first and second ceramic plates 14A, 14B move in the mutually separated directions, sliding is performed with the first and second inclined faces 15A, 15B left in mutual contact.

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, as shown in FIG. 9 (Japanese Patent Application No. 1-233751), a high-temperature slide valve of this type has an upstream plane 31 and an end surface 32 of a valve body 30.
By covering each portion with a plurality of ceramic plates 33, wear of this portion is suppressed. Above ceramic plate 3
3 is formed into a polygonal shape and is fixed to a metal base plate 36 of the valve body 30 by a metal fixing pin 35.

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 30 becomes high temperature, Fig. 10,
As shown in FIG. 11, the metal base plate 36 of the valve body 30 expands, and the ceramic plate 33A provided on the edge of the upstream plane 31 and the ceramic plate 33B provided on the end surface 32 are adjacent to each other. Gaps 37 were created between the surfaces, and the granular material entered these gaps 37.

[0004] After the high-temperature fluid has finished flowing, when the temperature of the valve body 30 decreases and returns to normal temperature, the metal base plate 36 contracts. Along with this, the gap 37 between the ceramic plates 33A, 33B tends to narrow, and the powder particles that have entered the gap 37 cause one end of each of the ceramic plates 33A, 33B to become narrower.
Bending forces FA and FB act in the direction of pushing and peeling off 33B. As a result, a large stress was applied to the pin hole 38 portion, which is the weakest portion, and a problem occurred in that the ceramic plates 33A, 33B were damaged from the pin hole 38 portion.

[0005] The present invention solves the above problem, and eliminates the problem that even if the valve body expands and contracts due to the thermal influence of high-temperature fluid, the ceramic plate covering the upstream plane and end face of the valve body is damaged. The object of the present invention is to provide a high temperature slide valve that can prevent the occurrence of such problems.

[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. A first ceramic plate is provided on the edge of the upstream plane of the valve body, a second ceramic plate adjacent to the first ceramic plate is provided on the end face of the valve body, and a pair of the first ceramic plate and the second ceramic plate are provided. Of the adjacent surfaces, the adjacent surface on the first ceramic plate side is formed as a first inclined surface, the adjacent surface on the second ceramic plate side is formed as a second inclined surface, and the second inclined surface is formed on the first inclined surface. A ceramic pin is provided that connects the first ceramic plate and the second ceramic plate to the valve body by covering and abutting with an inclined surface, and a distance from the ceramic pin that connects the first ceramic plate to the end face of the valve body. is L1, and the distance from the ceramic pin connecting the second ceramic plate to the upstream plane of the valve body is L2, then the inclination angle θ of the first inclined surface and the second inclined surface is expressed as θ= tan-
1 (L2/L1).

[0007]

[Operation] With the above configuration, the first ceramic plate and the second ceramic plate are connected to the edge of the upstream plane of the valve body by the ceramic pins, with the first inclined surface and the second inclined surface in contact with each other. attached to the section and end face.

[0008] When the valve body becomes high temperature due to the controlled fluid,
Since the metal base plate of the valve body thermally expands, the first ceramic plate and the second ceramic plate move in a direction away from each other. At this time, the amount of expansion of the base plate in the L1 direction is W1, the amount of expansion in the L2 direction is W2, and the amount of thermal expansion of the first and second ceramic plates themselves is the amount of thermal expansion W1, W2 of the metal base plate. It is ignored because it is minute compared to . As a result, any point on the first slope moves in the L2 direction by a movement amount W2, and any point on the second slope moves in the L1 direction by a movement amount W1.

Therefore, tan-1(W2/W1)=tan-1(L2/L1)
= θ, so when the base plate thermally expands, arbitrary points on the first and second slopes move on the same straight line with the slope angle θ. That is, the first inclined surface and the second inclined surface are in contact with each other in the same state as at normal temperature and move while sliding against each other. Therefore, due to thermal expansion,
Even if the first ceramic plate and the second ceramic plate move in a direction away from each other, a portion of the first inclined surface and a portion of the second inclined surface are in contact with each other. There is no gap between the two inclined surfaces.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 8. 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 forms a flow path for the controlled fluid 1. Further, a valve seat 3 is formed inside the valve box 2, and a flow path (
A valve body 4 that opens and closes the valve seat 3 is located 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. Then, a seat ring 6 that seals between the valve seat 3 and the valve body 4 is attached to the valve seat 3.
The seat ring 6 is in sliding contact with the valve body 4. A valve stem 9 inserted into the inside of the valve body 2 through the valve body cover (not shown) is connected to the base end of the valve body 4. ) is slidably supported.

[0012]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 hex steel 12 is filled with a wear-resistant lining material 13. ing.

Then, as shown in FIGS. 2 to 4, the valve body 4
is covered with a plurality of ceramic plates 14. These ceramic plates 14 are made of silicon nitride or the like and have excellent wear resistance. Furthermore, 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.

Among the ceramic plates 14, a first ceramic plate 14A is provided at the tip of the upstream plane 10 of the valve body 4, and a second ceramic plate 14B is provided at the end surface 11 of the valve body 4. As shown in FIGS. 5 and 6, the first ceramic plate 14A and the second ceramic plate 14B are arranged adjacent to each other, and the adjacent surface on the first ceramic plate 14A side is the first inclined surface 15A. Second ceramic plate 14B
The adjacent surface on the side is formed as a second inclined surface 15B. The first inclined surface 15A contacts the second inclined surface 15B and covers the second inclined surface 15B.

Each ceramic plate 14 including the first ceramic plate 14A and the second ceramic plate 14B is connected to the base plate 8 of the valve body 4 via a ceramic pin 17, respectively. A circumferential groove 18 is formed on the outer peripheral surface of the lower end of the ceramic pin 17, and a head 19 having a diameter larger than the body diameter of the pin is formed at the upper end of the ceramic pin 17.

A metal ring 20 is attached to the ceramic pin 17.
is fitted externally. The upper surface of this metal ring 20 can freely come into contact with and separate from the lower surface of the head 19 of the ceramic pin 17, and the outer peripheral surface of the metal ring 20 has a tapered surface 21 with a downward recess.
is formed. Furthermore, a metal cylindrical retainer 22 is fitted onto the lower part of the ceramic pin 17 . These retainers 22 are divided into two parts in the axial direction, and a protrusion 23 is formed in the inner peripheral surface of the retainer 22 in the circumferential direction so that the retainer 22 can be freely engaged with and detached from the groove 18 formed in the ceramic pin 17. There is.

[0017] The first and second ceramic plates 14A, 14
A pin hole 24 is formed in each ceramic plate 14 including B, and the head 19 of the ceramic pin 17 is removably fitted into the upper part of the pin hole 24, and the tapered surface formed at the lower part of the pin hole 24 25, the tapered surface 2 of the metal ring 20
1 is in contact. A pin holding hole 26 corresponding to the pin hole 24 is formed in the base plate 8, and a retainer 22 attached to the ceramic pin 17 is inserted into the pin holding hole 26. The lower end of the retainer 22 is fixed to the base plate 8 by welding. Thereby, the ceramic pin 17 is fixed to the base plate 8 and connects each ceramic plate 14 including the first and second ceramic plates 14A and 14B to the base plate 8.

The distance from the axis of the ceramic pin 17 connecting the first ceramic plate 14A to the end face 11 of the base plate 8 forming the valve body 4 is L1, and the axis of the ceramic pin 17 connecting the second ceramic plate 14B is defined as L1. If the distance from the upstream plane 10 of the base plate 8 is L2, then the first inclined surface 15A and the second inclined surface 15
The inclination angle θ of B is set so that θ=tan-1 (L2/L1).

The operation of the above configuration will be explained below. First ceramic plate 14A and second ceramic plate 14B
are attached to the edge portion and end surface 11 of the upstream plane 10 of the valve body 4 by ceramic pins 17, respectively, with the first inclined surface 15A and the second inclined surface 15B in contact with each other.

By operating the valve stem 9, the valve body 4 moves in and out, and the flow path in the valve seat 3 is expanded and contracted, thereby controlling the flow rate of the controlled fluid 1. At this time, since high temperature fluid flows, the valve body 4
The temperature changes from room temperature to high temperature. As a result, the base plate 8, which is a metal material, thermally expands. That is, as shown in FIGS. 7 and 8, the amount of expansion of the base plate 8 in the L1 direction at this time is W1, and the amount of expansion in the L2 direction is W.
2, and since the amount of thermal expansion of the first ceramic plate 14A and the second ceramic plate 14B themselves is minute compared to the above-mentioned amounts of thermal expansion W1 and W2 of the metal base plate 8, they are ignored. As a result, an arbitrary point A on the first inclined surface 15A moves in the L2 direction by the amount of movement W2 and shifts to point A', and also an arbitrary point A on the second inclined surface 15B that matches the above point A. Point B moves by a movement amount W1 in the L1 direction to point B'
Transition to.

Here, if the coefficient of linear expansion of the metal base plate 8 is α, then W1=α·L1 W2=α·L2. Therefore, tan-1(W2/W1)=tan-1[
(α・L2)/(α・L1)]
=tan-1(L
2/L1)

=θ
becomes.

In this way, the inclination angle of the straight line T passing through the points A' and B' is the same value (θ) as the inclination angles of the first inclined surface 15A and the second inclined surface 15B. The first inclined surface 15A and the second inclined surface 15B are in contact with each other in the same state as at normal temperature and move while sliding against each other. Therefore, even if the first ceramic plate 14A and the second ceramic plate 14B move away from each other due to thermal expansion, a portion of the first inclined surface 15A and a portion of the second inclined surface 15B will not come into contact with each other. Therefore, the first inclined surface 15A and the second inclined surface 1
There is no gap between it and 5B.

Furthermore, as the metal ring 20 thermally expands in the axial and radial directions, and the retainer 22 thermally expands in the axial direction together with the base plate 8, each of the metal rings including the first ceramic plate 14A and the second ceramic plate 14B Ceramic plate 14 is pressed against upstream plane 10 and end surface 11 of base plate 8 .

In the above embodiment, the ceramic pin 17 was provided in a removable manner on each ceramic plate 14, 14A, 14B.
, 14A, 14B may be integrally molded.

[0025]

As described above, according to the present invention, the second inclined surface of the second ceramic plate is covered and abutted with the first inclined surface of the first ceramic plate, and the ceramic connecting the first ceramic plates is When the distance from the pin to the end face of the valve body is L1, and the distance from the ceramic pin connecting the second ceramic plate to the upstream plane of the valve body is L2, the first inclined surface and the second inclined surface are The inclination angle θ is expressed as θ=tan-1(
L2/L1), when the base plate thermally expands, arbitrary points on the first and second slopes move on the same straight line with the slope angle θ.

[0026] That is, the first inclined surface and the second inclined surface are:
While touching each other in the same state as at room temperature, they move while sliding against each other. Therefore, even if the first ceramic plate and the second ceramic plate move away from each other due to thermal expansion, a portion of the first inclined surface and a portion of the second inclined surface remain in contact with each other. There is no gap between the first inclined surface and the second inclined surface.

[0027] This completely prevents the particles in the controlled fluid from entering between the first ceramic plate and the second ceramic plate, so the temperature of the valve body decreases and returns to normal temperature. This prevents a problem in which large stress is generated in the first and second ceramic plates due to the powder particles that have entered the gap, causing the first and second ceramic plates to be damaged.

[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 view taken along arrow A in FIG. 2;

FIG. 4 is a view taken along arrow B in FIG. 2;

FIG. 5 is a view along the line CC in FIG. 3;

FIG. 6 is a view taken along the line DD in FIG. 3;

FIG. 7 is a sectional view showing the movement of the ceramic plate when the valve body thermally expands in the same embodiment.

8 is an enlarged view of main parts in FIG. 7. FIG.

FIG. 9 is a perspective view of a valve body of a slide valve in a conventional example.

10 is a TT arrow view in FIG. 9. FIG.

FIG. 11 is a view taken along the line U-U in FIG. 9;

[Explanation of symbols]

1 Controlled fluid 2 Valve box 4 Valve body 7 Slide valve 8 Base plate 10 Upstream plane 11 End face 14A First ceramic plate 14B Second ceramic plate 15A First slope 15B Second slope 17 Ceramic pin L1 distance L2 distance θ　　　　Inclination angle

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 a first ceramic plate is provided at the edge of the upstream plane of the valve body. , a second ceramic plate adjacent to the first ceramic plate is provided on the end face of the valve body, and among the pair of adjacent surfaces of the first ceramic plate and the second ceramic plate, the adjacent surface on the first ceramic plate side is provided. a first inclined surface, an adjacent surface on the second ceramic plate side is formed as a second inclined surface, the second inclined surface is covered and abutted with the first inclined surface, and the first inclined surface and the first inclined surface are brought into contact with each other; Ceramic pins are provided that connect the second ceramic plates to the valve body, and the distance from the ceramic pin that connects the first ceramic plate to the end face of the valve body is L1, and the distance from the ceramic pin that connects the second ceramic plate to the end face of the valve body is L1. When the distance to the upstream plane of the valve body is L2, the inclination angle θ of the first inclined surface and the second inclined surface is θ=ta
A slide valve for high temperature, characterized in that the ratio is set to n-1 (L2/L1).