JPH0345264B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a high-temperature fluid flow rate control valve, and more particularly to a high-temperature fluid flow rate control valve that is used to control the flow rate of high-temperature, high-pressure compressed air blown into a blast furnace from a tuyere of a blast furnace. The present invention relates to a flow control valve that is particularly useful for use.

[Prior Art] As is well known, the tuyeres of a blast furnace e.g.
High-pressure, high-temperature air (hereinafter referred to as hot air) at 1300℃ and 3.5Kg/cm ² (gauge pressure) is blown at a high flow rate of 200m/sec or more. 30 to 50 such tuyeres are provided around the outer periphery of the blast furnace, and it is necessary to change the amount of hot air blown into the blast furnace from the tuyeres depending on the operational status of the blast furnace. For this reason, recently it has become possible to control the flow rate independently for each tuyere. In other words, even though the air flow rate is constant, the production volume increases and the furnace heat decreases due to changes in the reaction inside the furnace, or the extraction of hot metal and slag is insufficient because the tapping operation does not proceed smoothly. If this occurs, the amount of air blown will be increased or decreased as necessary, and during periods of increased production, the amount of air blown will be increased within the range allowed by the reaction in the furnace, especially the countercurrent reaction. As described above, with the advancement of blast furnace operating methods, opportunities to adjust the amount of hot air blown from the tuyeres are increasing, and for this reason, the control valves that adjust the amount of air blown are required to have fire resistance, heat resistance, and pressure resistance. There is a demand for a device with a large flow rate and a wide flow rate adjustment range.

By the way, attempts have been made to use control valves made of metal valve bodies as flow rate control valves for tuyeres, but since the valve body lacks heat resistance and cannot withstand high temperatures, the valve body has been water-cooled. Although this was attempted, the heat loss was large and it was not put to practical use.

For this reason, for example,
As shown in the publication, the valve body consists of a valve plate and valve stem made of ceramics, and a fireproof heat insulating material.
It has two semi-cylindrical casings that are horizontally divided into two parts from the center and each has a shaft hole drilled in the center part in the length direction, and the valve shaft is inserted into each shaft hole of both casings. A butterfly valve has been proposed in which a valve plate is housed in a flow path and both casings are integrally connected.

[Problems to be Solved by the Invention] In the butterfly valve as described above, the casing is horizontally divided into two semi-cylindrical parts, and a shaft hole is provided in the center to accommodate the valve body. It is difficult to fix and center the divided casing, and it is impossible to form a highly accurate circular cross section of the flow path.
For this reason, it was difficult to form a uniform gap between the valve plate and the inner wall of the flow path over the entire circumference, and the gap between the two had to be increased (with an inner diameter of 200 mm). In the flow path, the outer diameter of the valve plate is 170 mm,
Therefore, the distance will be approximately 15 mm). For this reason, even if the valve plate is fully closed, hot air is sent from the above-mentioned space, so the amount cannot be significantly restricted (flow rate Q when the valve plate is fully open and flow rate Q when it is fully closed _). (the ratio Q ₁ /Q is 50% or more), it was impossible to control the flow rate over a wide range.

In addition, the casing is said to be made of a fire-resistant insulation material such as castable refractories, but although such casings have excellent fire resistance, they have a low insulation effect and have a large heat loss. The outer cylinder may be deformed.

The present invention has been made in order to solve the above problems, and is a high-temperature fluid that can make the distance between the valve plate and the inner wall of the flow path uniform and as small as possible, and expand the adjustment range of the flow rate of hot air. The purpose of this is to obtain a flow rate control valve.

[Means for Solving the Problems] A flow rate control valve for high temperature fluid according to the present invention includes a cylindrical first heat-resistant member, a flow path in the center, and a length of the first heat-resistant member that is longer than the first heat-resistant member. A cylindrical second heat-resistant member fitted into the heat-resistant member of A heat-resistant member is inserted into both sides of a valve body disposed in the center of the casing to rotatably support the valve body via a bushing, and pressing members are provided on both sides of the first and second heat-resistant members. are fitted together, a fastener is attached to the outer periphery of the casing, and the fastener is welded to the inner wall of the casing to join them together.

[Operation] The first,
A second heat-resistant member is inserted, a presser member is fitted on both sides of the second heat-resistant member, and a fastener is attached to the outer circumference of the presser member and welded to the inner wall of the casing.

[Embodiment] FIG. 1 is a front view of an embodiment of the present invention, partially shown in cross section, and FIG. 2 is a side view thereof, partially shown in cross section. In both figures, 1 is a control valve according to the present invention, 2 is a valve body, 3 is a casing that accommodates the valve body,
5 is a driving section for the valve body 2.

In the valve body 2, 21 is a disc-shaped valve body, 22 is a valve shaft provided on the upper part of the valve plate 21, and 23 is a support shaft provided on the same line as the valve shaft 22 at the lower part of the valve plate 21. It is integrally constructed from ceramics.

In the casing 3, 31 is a steel outer cylinder having flanges 32, 32a, and 33 at both ends and the upper part, and 34, 34a are cylindrical tubes made of refractory bricks or the like and whose outer diameter matches the inner diameter of the outer cylinder 31. The heat-resistant member 1 has semicircular cutout portions 35, 35a formed in the upper portion thereof, into which the valve shaft 22 is inserted. 36,3
6a is a cylindrical second heat resistant member made of, for example, cement and whose outer diameter matches the inner diameter of the first heat resistant members 34, 34a and is longer than the first heat resistant members 34, 34a; 37 is a hot air flow path; 38, 38a are cut out parts provided on the inner periphery of the opposing part, 39, 39a are cut out parts 38,
The semicircular cutout portions 40 and 40a provided on the upper part of the valve shaft 38a and through which the valve shaft 22 is inserted are stepped portions cut out to the ends of the first heat-resistant members 34 and 34a at the outer periphery of the end portions.

41, 41a are ring-shaped support members made of ceramic, the outer diameter of which is the same as that of the second heat-resistant members 36, 3.
6a, and the inner diameter is the second
It is formed to match the inner diameter of the heat-resistant members 36, 36a, and thus the diameter of the flow path 37. 4
2,42a is a bush. Reference numerals 43 and 43a denote ring-shaped holding members made of a heat-resistant material, the outer diameter of which matches the inner diameter of the outer cylinder 31, the inner diameter of which matches the step portions 40 and 40a of the second heat-resistant members 36 and 36a, and the end portions of the holding members 43 and 43a. L-shaped cutout portions 44, 44a are formed in the portions. 45, 45a are ring-shaped fasteners, 46,
46a is a ground packing.

Next, an example of the assembly sequence of the flow control valve consisting of the above-mentioned parts will be explained. Support members 41 and 41a are connected to the valve shaft 22 and support shaft 23 of the valve body 2 from both sides via bushes 42 and 42a, and are accommodated in the outer cylinder 31 so that the valve shaft 22 projects upward. In this state, the second heat-resistant members 36, 36a are inserted from both sides, and the support members 41, 4 are inserted into the cutout portions 38, 38a.
1a and the semicircular cutout portions 39, 39a are fitted onto the valve shaft 22. Next, the first heat-resistant members 34, 34a are inserted into the outer periphery from both sides, the semicircular cut-out parts 35, 35a are fitted to the valve shaft 22, and the both sides and the second heat-resistant members 36, 36a are cut out. Part 40, 40a
The holding members 43, 43a are fitted into the holding members 43, 43a.

Next, a gland packing 46,
Fasteners 45, 45a are fitted through 46a, and these fasteners 45, 45a are welded to the inner wall of the outer cylinder 31 to join them together. Finally, the control valve 1 is completed by connecting the valve shaft 22 and the output shaft of the motor 51 and fixing the cover 52 to the flange 33.

The above description shows an example of the assembly order of the present invention, and may be changed as appropriate, for example, by fitting the first heat-resistant members 34, 34a and then fitting the second heat-resistant members 34, 34a. Needless to say.

In the flow control valve of the present invention configured as described above, the control valve 1 is connected to the air blowing pipe of the tuyere through the flanges 32, 32a, and the motor 51 of the drive unit 5
If the valve stem 22 is rotated by the
2 and support shaft 23 as axes, and the flow rate of hot air flowing through the flow path 37 can be adjusted over a wide range.

In the above embodiment, the control valve according to the present invention is used to control the flow rate of hot air blown into the blast furnace tuyere, but it goes without saying that it can also be used to control other high-temperature fluids. do not have.

[Effects of the Invention] As is clear from the above description, the present invention has a symmetrical structure in which the first and second heat-resistant members are divided into two from the center in the valve axis direction, and are disposed at the center inside the outer cylinder. inserted into both sides of the valve body to rotatably support the valve body,
A presser member with a symmetrical structure is fitted to the outer periphery of both heat-resistant members, and a stopper is attached to the outer periphery of the presser member and welded to the inner wall of the outer cylinder, so that they are connected and fixed as one body. The cross section of the road can be formed into a circular shape with high precision. Therefore, the distance between the valve plate and the inner wall of the flow path can be made as small as possible, and the range of adjustment of the flow rate of high-temperature fluid can be greatly expanded.

In addition, since the flow path is constructed by doubly bonding the first heat-resistant member made of refractory material and the second heat-resistant member made of cement or the like, heat loss of the high-temperature fluid flowing in the flow path can be reduced. At the same time, deformation of the outer cylinder due to heat can be prevented.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the present invention, partially shown in cross section, and FIG. 2 is a side view thereof, partially shown in cross section. 1: Control valve, 2: Valve body, 3: Casing, 5:
Valve body drive unit, 31: outer cylinder, 34, 34a: first
heat-resistant member, 36, 36a: second heat-resistant member, 3
7: Channel, 43, 43a: Pressing member, 45, 45
a: Fastener.

Claims (1)

[Scope of Claims] 1. A control valve in which a valve body made of ceramics is rotatably disposed in a casing in which a flow path is formed by a heat-resistant member, comprising: a cylindrical first heat-resistant member; The first heat-resistant member has a flow path in the length direction of the center and is longer than the first heat-resistant member.
A cylindrical second heat-resistant member fitted into the heat-resistant member of heat-resistant members are inserted into both sides of a valve body disposed in the center of the casing to rotatably support the valve body via a bushing, and
A presser member is fitted on both sides of the second heat-resistant member, a fastener is attached to the outer periphery of the second heat-resistant member, and the fastener is welded to the inner wall of the casing to connect them together. Flow control valve.