KR20150117181A - Butterfly valve having quadruple eccentric structure - Google Patents

Abstract

The present invention relates to a butterfly valve of a fourfold eccentric structure capable of maintaining excellent air tightness under two-way fluid flow in a high pressure condition. In the butterfly valve wherein a conical valve disk is installed inside a hollow valve body to be able to rotate by a valve shaft, an embodiment of the present invention is to provide the butterfly valve of the fourfold eccentric structure wherein a sheet unit is protruded from the inside diameter side of the valve body by being separated from an interfacial center line of the valve body to a longitudinal direction along one side of the valve body, and a valve shaft is installed by being separated from a euro centerline of the valve body to a width direction along one side of the valve body. In the valve disk, a reference axial line of a cone angle is rotated as a predetermined angle for the euro centerline about an intersection point of the interfacial centerline and the euro centerline. A center line on a longitudinal section is rotated at a predetermined angle for the interfacial center line and is installed to be tilted.

Description

[0001] The present invention relates to a butterfly valve having a quadruple eccentric structure,

The present invention relates to a butterfly valve that is installed in a piping to control or shut off a flow rate. More specifically, the present invention relates to a butterfly valve having a quadruple eccentric structure capable of maintaining excellent airtightness under both high- Of the butterfly valve.

Generally, a butterfly valve is a valve having a structure in which a valve disk is rotatably installed inside a valve body connected to a pipe, and a valve disk is rotated by a driving device connected to the valve shaft to open and close the flow path.

Butterfly valves can be broadly classified into concentric and eccentric types.

1 shows a cross section of a conventional concentric butterfly valve in which the sealing surface of the valve and the center of the valve body 1, the valve disc 2 and the valve shaft 3 are arranged on the same line.

That is, the valve disc 2 is installed symmetrically about the central axis of the valve shaft 1 on the vertical plane and is vertically symmetrical about the central axis of the valve body 1 Structure.

Concentric type butterfly valves are widely used for low temperature and low pressure applications and have a good airtightness at low pressure.

However, since the valve disc 2 is sealed while directly pressing the rubber sheet 4 for airtightness, the damage rate of the rubber sheet 4 is high and the friction between the valve disc 2 and the rubber sheet 4 is severe, There is a problem in that the airtightness is rapidly deteriorated. Further, at high temperatures, high pressures, or extremely low temperatures, it is difficult to maintain the airtightness due to deformation of the material, and the use thereof is limited.

On the other hand, the centrifugal type butterfly valve has an advantage that the valve disc is disposed eccentrically apart from the center of the inside of the valve body, so that the operating torque is smaller and the damage rate of the seat portion is smaller than that of the above-

An eccentric type butterfly valve is classified into a single offset type, a double offset type, and a triple offset type according to the number of eccentricity of a valve disk.

FIG. 2 is a cross-sectional view showing the structure of a triple offset type butterfly valve disclosed in Korean Patent Laid-Open No. 10-2011-0024133 (Patent Document 1). The valve disk 20 includes a valve shaft 30 And the valve shaft 30 is secondarily eccentrically spaced apart from the line A-A ', which is the line center line of the valve, by a predetermined distance ("b"), A reference axis C-C 'in the shape of a cone having a vertex at an intersection T at which the valve disk 20 and the valve body 10 extend in a line extending from the line A-A' And the reference axis C-C 'is rotated by a predetermined angle (?) So that the intersection T is located within the diameter range of the valve disc 20.

The triple offset type butterfly valve shown in FIG. 2 has an advantage of minimizing deformation even under high temperature and high pressure conditions to maintain sufficient airtightness. However, since the structure of the valve disc 20 has a vertex T So that the airtightness is ensured only in the unidirectional fluid flow condition, and it is not compatible with the bidirectional fluid flow condition.

That is, when the fluid flow in the valve body 10 is in the direction in which the valve disc 20 is pressed toward the seat portion 40 (from right to left in the figure) The airtightness is deteriorated in the direction away from the seat portion 40 (from left to right in the drawing), which is disadvantageous in that it is not suitable for continuously enduring repetitive pressure of the bidirectional fluid flow.

KR 10-2011-0024133 A (Mar. open)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems as described above, and an embodiment of the present invention provides a butterfly valve of a quadruple eccentric structure capable of maintaining excellent airtightness under bidirectional fluid flow conditions under high temperature and high pressure conditions. .

According to a preferred embodiment of the present invention, there is provided a butterfly valve in which a conical valve disk is rotatably installed by a valve shaft in a valve body having a hollow, the butterfly valve comprising: And the valve disc is spaced apart from the center line of the valve body in the width direction of the valve body so that the valve disc is spaced apart from the reference axis of the cone angle, And the longitudinal center line is inclined at a predetermined angle with respect to the center line between the center and the center line. A valve is provided.

At this time, the center line of the seat portion is firstly eccentrically separated from the center line between the centers by "a ", and the center of the valve shaft is secondarily eccentrically separated from the flow path center line by" b " Is rotated by an angle "c" with respect to the passage center line, and the longitudinal centerline of the valve disc is rotated by an angle "d"

At this time, the vertex of the cone angle is located outside the flow path of the valve body.

That is, the point of intersection of the upper extension line and the lower extension line of the valve disc on the end surface is located outside the imaginary extension line formed by extending the inner diameter surface of the valve body on the longitudinal plane.

The center line of the valve disc on the end surface is disposed close to the one end edge line of the valve body so that an imaginary extension line connecting the upper or lower end of the valve disc and the intersection does not pass through the body of the valve body .

In addition, the valve disc has a quadrilateral shape in which the upper and lower ends on the longitudinal plane are inclined in the same direction.

At this time, it is preferable that the inclination angle of the upper end of the valve disc and the inclination angle of the lower end of the valve disc are different from each other.

According to the butterfly valve having the quadruple eccentric structure according to the preferred embodiment of the present invention, the fluidity and the airtightness of the valve disk are secured, thereby maximizing the flow control and shutoff function for the bidirectional fluid flow.

In addition, wear due to friction between the valve disc and the seat portion is minimized, thereby improving the durability of the valve.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of a conventional concentric butterfly valve.
2 is a sectional view of a conventional triple offset type butterfly valve.
3 is a sectional view of a butterfly valve of a quadruple eccentric structure according to an embodiment of the present invention.
4 is a schematic sectional view showing the machining interference of the conical valve disk;
5 is a sectional view of a butterfly valve of a quadruple eccentric structure according to another embodiment of the present invention.
6 is a cross-sectional view showing pressure, force, area and moment acting on a butterfly valve of a quadruple eccentric structure according to an embodiment of the present invention;

Hereinafter, preferred embodiments of a butterfly valve having a quadruple eccentric structure according to the present invention will be described with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation.

In addition, the terms described below are defined in consideration of the functions of the present invention, which may vary depending on the intention or custom of the user, the operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are not to be construed as limiting the scope or spirit of the invention as disclosed in the accompanying claims. Embodiments that include components replaceable as equivalents in the elements may be included within the scope of the present invention.

Example

3 is a cross-sectional view of a butterfly valve having a quadruple eccentric structure according to an embodiment of the present invention.

3, a butterfly valve (hereinafter, referred to as a 'butterfly valve') 100 having a quadruple eccentric structure according to an embodiment of the present invention includes a hollow valve body 200, And a valve disc 400 that rotates about the valve shaft 300 within the valve body 200 to regulate or block the flow and flow of the fluid.

At this time, the hollow of the valve body 200 forms a fluid passage through which the fluid flows, and the inner surface of the valve body 200 is provided with a seat portion 211 Is protruded.

The valve disc 400 is formed in a disc shape as a whole and has a valve shaft 400 at one side of the center of the valve disc 400 and a valve shaft 300 The shaft coupling portion 410 is protruded.

The valve shaft 300 is installed to penetrate through the valve body 200 and the shaft coupling portion 410. One end of the valve shaft 300 extending to the outside of the valve body 200 is connected to the valve body 200 by a driving device The valve disc 400 integrally rotates together with the valve shaft 300 to open and close the flow path inside the valve body 200. [

According to an embodiment of the present invention, the valve disc 400 is installed in the valve body 200 in a quadruple eccentric structure.

The center of the valve shaft 300 installed to penetrate the shaft coupling portion 410 of the valve disc 400 is located on the center line B-B 'of the valve body 200.

At this time, since the shaft coupling part 410 is protruded at one side of the valve disc 400, the valve disc 400 is moved from the center line B-B 'of the valve body 200 to the length of the valve body 200 (The right side in the figure) with a predetermined interval.

The center of the valve shaft 300 extends from one side in the width direction (lower side in the figure) of the valve body 200 along the center line B-B ' So that the valve disc 400 is secondarily eccentric.

The valve disc 400 is formed with an inclined surface along the rim and has a generally conical shape. At this time, when the imaginary extension line is drawn from the slope of the edge of the valve disc 400, the extension lines of the valve disc 400 and the extension line extending from the edge slope of the valve disc 400 meet at the intersection point C ' e).

At this time, the valve disc 400 is rotated about the axis line center line A (A) with reference to the point of intersection of the reference axis C-C 'of the cone angle e with the flow path center line A-A' -A ') so that the valve disc 400 is thirdly eccentric.

In addition, the valve disc 400 is installed such that the longitudinal center line D-D 'is inclined by a predetermined angle with respect to the center line B-B', so that the valve disc 400 is fourtharily eccentric.

That is, the butterfly valve 100 according to the embodiment of the present invention is configured such that the center line of the valve disc 400 (or the center line of the valve disc 400 The center line D-D 'is spaced apart from the center line B-B' by "a".

By the secondary eccentricity, the center of the valve shaft 300 is spaced apart from the flow path center line A-A 'along the center line B-B' by "b".

The reference axis line C-C 'of the cone angle e formed by the inclined surfaces of the rim of the valve disc 400 is shifted from the flow path center line A-A' to the inter-plane center line B- Quot; c "centered on the intersection of the two points.

The center line D-D 'of the valve disc 400 is rotated and positioned at an angle "d" with respect to the center line B-B' by the fourth eccentricity.

At this time, in order to increase the reaction force of the seat portion 211 with respect to the bidirectional flow of the high-pressure fluid in order to improve airtightness, the upper and lower ends of the quadrangle gfhi including the contact surface of the valve portion disk 400 and the seat portion 211 It is preferable to be inclined in the same direction.

For example, in the embodiment shown in Fig. 3, the inclined surfaces g-f and h-i at the upper and lower ends of the valve disk 400 are all inclined downward in the drawing.

On the other hand, in the conventional example shown in Fig. 2, the inclined surface at the upper end of the valve disc 20 is inclined upward, and the inclined surface at the lower end is inclined downward. Therefore, when the flow of the fluid is left to the right in the drawing, the rim of the valve disc 20 is pressed toward the seat portion 40 so that the airtightness is good. In the opposite direction, It was too weak to sustain the pressure continuously.

However, in the case of the present invention shown in Fig. 3, when the flow of the fluid is from the right to the left in the drawing, the lower end slope hi of the valve disk 400 is pressed toward the seat portion 211, In the drawing, the upper inclined surface gf is pressed toward the seat portion 211 in the case of the left side to the right side, so that the repetitive pressure of the bidirectional fluid flow can be sustained continuously.

For this purpose, the vertex of the cone angle e with respect to the conical valve disk 400 should be located outside the flow path of the valve body 200.

3, the intersection C 'of the extension line of the upper end surface of the valve disk 400 and the extension line hi of the lower end of the valve disk 400 is larger than the intersection point C' And is located outside the imaginary extension line 1 formed by extending the extension line.

In order to increase the reaction force of the seat portion 211 with respect to the bidirectional flow of the high-pressure fluid, it is preferable to maximize the inclination angle d and the cone angle e of the valve disk 400, It is preferable that one edge of the valve disc 400 is disposed as close as possible to one edge of the valve body 200 in order to maximize the inclination angle d and the cone angle e of the valve body 400. That is, the center line D-D 'of the valve disk 400 (or the seat portion 211) on the end face should be as close as possible to the one end edge line L-L' of the valve body 200.

4 is a schematic cross-sectional view showing the machining interference of the conical valve disk, in which the line F-F 'indicates the machining start surface of the seat portion 211 and the line G-G' indicates the machining end surface of the seat portion 211.

The center line D-D 'of the seat portion 211 is spaced apart from the one-end frame line L-L' of the valve body 200 and positioned near the inter-centerline B- , The inner diameter surface H-H 'of the valve body 200 is interfered with the conical working line I-I', and the machining interference amount H'-H "-I" is generated.

In this case, as shown by the dotted line, the inner surface J-J 'and the outer diameter surface of the valve body 200 are curved to avoid machining interference. The inclination angle d of the valve disc 400 and As the cone angle e becomes larger, the machining interference amount (H'-H "-I") increases more and the inner radius J-J 'and the curvature of the outer radius surface for avoiding such machining interference have to be larger .

However, such a curved surface machining is not only difficult to work but also increases production cost and time due to an increase in airflow, and causes material waste, which is a factor of productivity deterioration.

Therefore, in order to maximize the inclination angle d and the cone angle e of the valve disc 400 without interfering with the processing, the center line (or the center line) of the valve disc 400 (or the seat portion 211) D-D ') should be designed so as to be as close as possible to one end edge line L-L' of the valve body 200.

5 is a cross-sectional view of a butterfly valve 100 'having a quadruple eccentric structure according to another embodiment of the present invention, in which the valve disc 400 and the seat portion 211 are in contact with the metal sheet 500 to be.

To this end, a disk retainer ring 420 is bolted to one side of the rim of the valve disk 400, and a body retainer ring 212 is bolted to one side of the seat portion 211. A metal sheet 500 is interposed between the valve disc 400 and the disc retainer ring 420 and between the seat portion 211 and the body retainer ring 212 so as to face each other.

At this time, it is also possible that the metal sheet 500 is provided in only one of the valve disc 400 and the seat portion 211. That is, a metal sheet 500 may be provided only on the valve disc 400, or a metal sheet 500 may be provided only on the seat portion 211.

6 is a cross-sectional view showing pressure, force, area, and moment acting on a butterfly valve of a quadruple eccentric structure according to an embodiment of the present invention.

Referring to FIG. 6, when the pressure of the fluid acts on the butterfly valve 100, the pressure applied to the butterfly valve 100 varies according to the flow direction of the fluid.

And the pressure generated when the fluid acts in the forward or backward flow on the butterfly valve 100 is represented by P, the forward flow (right to left in the drawing) corresponds to the quadruple eccentric structure according to an embodiment of the present invention. The area of A1 is larger than the area of A2, r1 is larger than r2, and the turning radius is also increased, and the result of the moment M1 > M2 is obtained.

Further, in the case of the reverse flow (from the left to the right in the drawing), the area of A4 is larger than the area of A3, r4 is larger than r3, and the turning radius also becomes larger, so the result of the moment value is M3 < M4.

That is, according to the embodiment of the present invention, since the butterfly valve 100 can receive the pressure in a distributed manner according to the forward flow and the reverse flow of the fluid, the durability is improved and the operation life is prolonged.

100: Butterfly valve
200: Valve body
210: Body
211: seat portion
220: hollow
300: valve shaft
400: valve disc
410: shaft coupling portion
500: metal sheet

Claims (7)

A butterfly valve in which a conical valve disk (400) is rotatably mounted by a valve shaft (300) in a valve body (200) having a hollow (220)
A seat portion 211 is formed on the inner surface of the valve body 200 so as to protrude from the center line B-B 'of the valve body 200 in the longitudinal direction of the valve body 200,
The valve shaft 300 is installed to be spaced apart from the flow path center line A-A 'of the valve body 200 in the width direction of the valve body 200,
The valve disc (400)
The reference axis C-C 'of the cone angle e is formed with respect to the flow path center line A-A' with reference to the intersection point of the inter-surface center line B-B 'and the flow path center line A- , And the longitudinal center line (D-D ') is inclined by a predetermined angle with respect to the inter-phase center line (B-B').
The method according to claim 1,
The center line D-D 'of the seat portion 211 is firstly eccentrically spaced from the inter-surface center line B-B' by "a"
The center of the valve shaft 300 is secondarily eccentrically spaced from the flow-path center line A-A 'by "b"
The reference axis C-C 'of the valve disc 400 rotates by an angle "c " with respect to the flow path center line A-A'
Wherein the longitudinal center line D-D 'of the valve disc 400 is rotated by an angle "d" with respect to the center line B-B' to be quadratically decentered. valve.
The method according to claim 1,
And a vertex of the cone angle (e) is located outside the flow path of the valve body (200).
The method according to claim 1,
The intersection C 'of the upper extension line and the lower extension line of the valve disc 400 on the end face is located outside the imaginary extension line 1 formed by extending the inner diameter face of the valve body 200 on the longitudinal plane 4-eccentric butterfly valve.
The method of claim 4,
The center line of the valve disc 400 on the end face is set so that a virtual extension line connecting the upper or lower end of the valve disc 400 and the intersection C 'does not pass through the body 210 of the valve body 200. [ D-D ') is disposed close to one end edge line (L-L') of the valve body (200).
The method according to claim 1,
Wherein the valve disc (400) has a quadrilateral eccentric structure in which the upper and lower ends of the valve disc (400) are inclined in the same direction.
The method of claim 6,
Wherein the valve disc (400) has a tilt angle of the upper end (gf) and a tilt angle of the lower end (hi) different from each other.

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