CN211202903U

CN211202903U - Four-eccentric butterfly valve

Info

Publication number: CN211202903U
Application number: CN201922055056.8U
Authority: CN
Inventors: 林凯宇; 邢懿; 黄赛荣; 徐艳华; 刘辉
Original assignee: Jiangsu Shentong Valve Co Ltd
Current assignee: Jiangsu Shentong Valve Co Ltd
Priority date: 2019-11-26
Filing date: 2019-11-26
Publication date: 2020-08-07
Anticipated expiration: 2029-11-26

Abstract

The utility model provides a four eccentric butterfly valves, which comprises a valve body, the sealing washer, the sealing backing ring, a pressing plate, the butterfly plate, the valve rod, the sealing backing ring is installed on the step of butterfly plate, the sealing washer is pressed on the sealing backing ring, the clamp plate passes through bolted connection butterfly plate, the valve rod passes through the pin junction butterfly plate, sealed face is the perfect circle sealed face on the valve body, the valve rod central line is first off-centre with the eccentricity e of sealed face central line, the valve rod central line is second off-centre with the eccentricity b of butterfly valve passageway central line, the cone central line that the sealed face of sealing washer formed forms contained angle α with butterfly valve passageway central line and is the third off-centre, the minor axis length of oval sealed face in the sealed face cone prolongs the two-way each extension eccentricity f of minor axis, make its minor axis and major axis equal, eccentricity f is the fourth off-centre, the beneficial effects of the utility model are, accomplish the transition of oval sealed face to the perfect.

Description

Four-eccentric butterfly valve

Technical Field

The utility model relates to a butterfly valve, especially a four eccentric butterfly valves.

Background

Butterfly valves have experienced the evolution of several structural forms, namely a center line butterfly valve, a single-eccentric butterfly valve, a double-eccentric butterfly valve and a triple-eccentric butterfly valve, in the history of their development.

At present, the three-eccentric butterfly valve is a butterfly valve form with wide application range and good use effect, the three-eccentric butterfly valve is characterized in that a second eccentric angle is added on the basis of a double-eccentric butterfly valve to reduce a second eccentric distance and further reduce the opening torque, but the sealing surface of the three-eccentric butterfly valve is not a circle but an ellipse, and the sealing mode of the three-eccentric butterfly valve is changed from position sealing to torsion sealing, so that the three-eccentric butterfly valve is suitable for being used for metal hard sealing, can resist high temperature and high pressure, has the function that the valve is closed more and more tightly, and has zero leakage in the sealing effect.

However, the three-eccentric butterfly valve has obvious disadvantages, and the elliptical sealing surface of the three-eccentric butterfly valve has the problems of uneven stress distribution and uneven wear of the sealing surface under the combined action of medium pressure and torque force of a driving device, for example, as shown in a sealing surface stress distribution diagram in fig. 1, when the sealing surface is subjected to the medium pressure, the stress at the short axis of the ellipse is concentrated, and the stress at the long axis of the ellipse is dispersed, so that the friction force between the sealing ring at the short axis and the sealing position on the valve body is the largest, and the friction force between the sealing ring at the long axis and the sealing position on the valve body is the smallest, so that the whole sealing ring is unevenly worn, and after multiple opening and closing actions, the short axis of the sealing surface of the butterfly valve leaks firstly, so that the.

SUMMERY OF THE UTILITY MODEL

For overcoming above-mentioned prior art problem, the utility model provides a make sealed face stress distribution even, guarantee the sealing washer through opening and close the back many times, the micro-wear of whole sealed face is also even, fundamentally solves the sealed face minor axis department wearing and tearing of oval sealing face originally fast, the sealed leakage problem that major axis department wearing and tearing lead to slowly, improves the life's of butterfly valve sealing performance and sealing washer four eccentric butterfly valves.

The technical scheme of the utility model be, a four eccentric butterfly valves, which comprises a valve body, the sealing washer, the sealing backing ring, the clamp plate, the butterfly plate, the valve rod, the sealing backing ring is installed on the step of butterfly plate, the sealing washer is pressed on the sealing backing ring, the clamp plate passes through bolted connection butterfly plate, the valve rod passes through the pin junction butterfly plate, sealed face is the perfect circle sealed face on the valve body, valve rod central line is first off-centre with the eccentricity e of sealed face central line, valve rod central line is second off-centre with the eccentricity b of butterfly valve passageway central line, the cone central line that the sealed face of sealing washer formed forms contained angle α with butterfly valve passageway central line and is the third off-centre, the minor axis length of oval sealed face in the sealed face cone prolongs the two-way each extension eccentricity f of minor axis, make its minor axis and major axis.

The utility model has the advantages that the conversion from the elliptical sealing surface to the perfect circular sealing surface is completed by adding an eccentric center, the problems of the traditional three-eccentric butterfly valve that the stress distribution of the elliptical sealing surface is uneven, the abrasion of the minor axis of the elliptical sealing surface is fast, and the abrasion of the major axis is slow, which causes the sealing leakage, can realize the zero leakage for a long time, and prolong the service life of the four-eccentric butterfly valve sealing ring; meanwhile, the shape of the sealing surface of the four-eccentric butterfly valve is changed, so that the second eccentricity of the four-eccentric butterfly valve can be designed to be smaller on the premise that the four-eccentric butterfly valve does not interfere with the sealing surface, the torque of the four-eccentric butterfly valve is reduced, and the model selection cost of the driving device is reduced.

Drawings

FIG. 1 is a graph of the stress distribution of a sealing surface of a conventional triple offset butterfly valve;

FIG. 2 is a schematic view of a sealing surface right circular cone of a conventional triple offset butterfly valve;

FIG. 3 is a schematic view of a sealing surface right circular cone of a conventional triple offset butterfly valve in the direction of A;

FIG. 4 is a top view of a sealing surface of a prior art triple offset butterfly valve;

FIG. 5 is a schematic structural view of the present invention;

FIG. 6 is a schematic view of an elliptical cone of a sealing surface in the structure of the present invention;

FIG. 7 is a schematic view of the sealing surface with an elliptic cone in the structure of the present invention in the direction A;

FIG. 8 is a top view of a sealing surface in the structure of the present invention;

FIG. 9 is a stress distribution diagram of a sealing surface of the middle valve of the present invention;

FIG. 10 is a three-dimensional view of a right circular cone formed by a sealing surface of a conventional triple offset butterfly valve;

fig. 11 is a three-dimensional view of an elliptical cone formed by the sealing surface of the present invention;

fig. 12 is a projection of an elliptical cone formed by the seal ring in the XOY plane according to the present invention;

fig. 13 is a projection of an elliptical cone formed by the sealing ring in the OGH plane according to the present invention;

FIG. 14 is a cross-sectional view of the plane defined by G1H1 and A1B1 intersecting an elliptical cone;

FIG. 15 is a bottom elevational view of the cone of FIG. 11.

In the figure, 1, a valve body, 2, a sealing ring, 3, a sealing gasket ring, 4, a pressure plate, 5, a butterfly plate, 6, a valve rod, e, a first eccentricity, b, a second eccentricity, α, a third eccentricity and f, a fourth eccentricity are included.

Detailed Description

As shown in fig. 5-9, a four-eccentric butterfly valve includes a valve body, a seal ring, a pressure plate, a butterfly plate, and a valve rod, the seal ring is mounted on a step of the butterfly plate, the seal ring is pressed on the seal ring, the pressure plate is connected to the butterfly plate through a bolt, the valve rod is connected to the butterfly plate through a pin, a sealing surface on the valve body is a perfect circle sealing surface, an eccentric distance e between a center line of the valve rod and a center line of the sealing surface is a first eccentricity, an eccentric distance b between the center line of the valve rod and a center line of a channel of the butterfly valve is a second eccentricity, an included angle α formed between a center line of a cone formed by the sealing surface of the seal ring and the center line of the channel of the butterfly valve is a third eccentricity, a length of a short axis of.

Designing a calculation principle:

as shown in fig. 10, the bottom surface is a perfect circle, the diameter thereof is the length of AB, the radius thereof is r, the included angle between any generatrix and the central line of the cone is θ, the vertex O of the perfect cone is the origin of the spatial rectangular coordinate system, the plane perpendicular to the linear CD is the X axis, the plane parallel to the linear CD is the Y axis, the plane perpendicular to the XOY is the Z axis, the spatial rectangular coordinate system is established, the figures obtained by beveling the generatrix of the ellipse with any plane are standard elliptical surfaces, the plane of the linear CD and the plane of the linear EF are parallel to each other, and the upper and lower two surfaces cut by the two planes cutting the perfect cone are elliptical surfaces, the formed solid figure is the sealing ring of the three-eccentric butterfly valve, the bottom surface of the perfect cone is respectively extended and stretched along the three-eccentric minor axis in two directions (i.e. the Z axis direction) until the elliptical sealing surface is a perfect circle, at this time, the perfect cone has become an elliptical cone, the perfect circle of the bottom surface is already an ellipse, and the eccentricity f of the bottom surface in the Z-axis direction is a fourth eccentricity.

As shown in FIG. 11, the bottom surface is an ellipse, the straight line AB is a minor axis of the ellipse, the straight line GH is a major axis of the ellipse, the angle corresponding to the minor axis in the XOY plane is θ, and the angle corresponding to the major axis in the XOZ plane is θ, and the angle corresponding to the minor axis is θ, and the angle corresponding to the major axis is θ₁The plane that sharp CD belonged to intersects the figure that obtains with the elliptical cone and is just in time the utility model discloses a sealing washer, its upper and lower both ends face are the perfect circle, and the plane that sharp EF belonged to is parallel with the plane that sharp CD belonged to, and its figure that intersects the elliptical cone and also is the perfect circle, and the plane that sharp CD belonged to and the real object that the plane that sharp EF belonged to was cut out is the perfect circle. Taking XOY plane as a research coordinate system, the projection of the elliptic cone in the XOY plane is shown in FIG. 12, wherein the straight line AB is the short axis of the elliptic cone, the point S is the middle point of the straight line AB, the straight line OS is the central line of the elliptic cone (namely the straight line OS is vertical to the straight line AB), the straight line OS is intersected with the straight line CD at the point P, the middle point I of the straight line CD is taken, the OI is connected, the straight line OI is extended, the straight line AB is intersected with the point T, any plane parallel to the plane of the straight line CD is used for cutting the elliptic cone, the cut planes are all right circular planes, the central point of any right circular is on the straight line OT, the passing point I is taken as the vertical line of the straight line OS, the straight line OS is on the point Q, the vertical point is taken as the point Q₁AC-DC line OA at point A₁The passing point D is a perpendicular line of the straight line OS, the straight line OS is crossed with the point K, and the straight line OS and the center line of the channel in the valve body are arrangedThe included angle of (a) is α,

。

in this elliptical cone, only theta is derived₁The elliptic cone can be determined as a function of θ, α, and the value of the fourth eccentricity f can be derived by further geometric transformation, where θ and α are given by the designer as design input parameters, and the detailed calculation process is as follows:

taking fig. 12 as an example, the calculation is as follows:

in △ ODK:

in △ OCD:

，

passing through point Q, making parallel line of straight line CD, and intersecting with extension line of straight line KD at point D₁And is and

。

at △ KQD₁The method comprises the following steps:

in △ KDP:

in △ IPQ:

at △ OQA₁The method comprises the following steps:

in FIG. 11, the projection of the elliptical cone in the plane formed by the OGH is shown in FIG. 13, and the straight line G in FIG. 13₁H₁In the plane of the line A in FIG. 11₁B₁The plane is the same plane, the figure obtained by the intersection of the plane and the elliptic cone is an ellipse parallel to the elliptic cone bottom, and when the view is seen from the direction vertical to the elliptic plane, the figure 14 is obtained, wherein A₁B₁Is the minor axis of the ellipse, G₁H₁A new rectangular coordinate system X is established for the major axis of the ellipse with the point S in FIG. 14 as the origin₁SY₁。

At △ OQG of FIG. 13₁The method comprises the following steps:

in fig. 14:

the ellipse is in rectangular coordinate system X₁SY₁The ellipse equation in (1) is:

point I₂The coordinate is (X)_I- | IQ |), i.e. (X)_I，-

）

Handle I₂Coordinates, | G₁O|、|A₁The value of O | is substituted into the ellipse equation:

after the solution is solved into a quadratic equation, the difference of the two solutions is solved:

i.e. point I₁And point I₂The length of the space is:

in fig. 14, since a graph in which a plane on which a straight line CD is located intersects an elliptical cone is a perfect circle and a point I is a center of the perfect circle, a diameter = | CD | = | I of the perfect circle₁I₂|

Namely:

(relational expression 1)

As can be seen from the above, the relation 1 relates to θ₁Theta, αWherein theta and α are design input parameters, the butterfly valve designer defines itself according to company internal standards, theta₁The numerical value can be calculated according to the relation.

Returning to the elliptical cone of fig. 11:

and r is the radius of the base circle of the right circular cone before stretching the elliptic cone

Namely:

namely:

in △ OAS of FIG. 12:

in △ OGS of FIG. 13:

FIG. 15 is a bottom elevational view of the cone of FIG. 11:

in fig. 15: the value of the fourth eccentricity f is:

(relational expression 2)

In summary, the relation 2 relates to θ₁And theta and r, wherein the theta and the r belong to design self-defined input parameters, the value of the fourth eccentricity f is obtained through the relational expression 2, after all the parameters are determined, the key parameters of the design of the four-eccentricity butterfly valve are known, and the design of other parts is designed according to the relevant standard.

The technical scheme completes the conversion from the elliptical sealing surface to the perfect circular sealing surface by adding one eccentric center, solves the problems of sealing leakage caused by uneven stress distribution of the elliptical sealing surface, fast abrasion at the short axis and slow abrasion at the long axis of the elliptical sealing surface of the traditional three-eccentric center butterfly valve, can realize zero leakage for a long time, and prolongs the service life of the sealing ring of the four-eccentric center butterfly valve; meanwhile, the shape of the sealing surface of the four-eccentric butterfly valve is changed, so that the second eccentricity of the four-eccentric butterfly valve can be designed to be smaller on the premise that the four-eccentric butterfly valve does not interfere with the sealing surface, the torque of the four-eccentric butterfly valve is reduced, and the model selection cost of the driving device is reduced.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications to the present embodiment without inventive contribution as required after reading the present specification, but all of them are protected by patent laws within the scope of the claims of the present invention.

Claims

1. A four-eccentric butterfly valve comprises a valve body, a sealing ring, a sealing gasket ring, a pressing plate, a butterfly plate and a valve rod, wherein the sealing gasket ring is installed on a step of the butterfly plate, the sealing ring is pressed on the sealing gasket ring, the pressing plate is connected with the butterfly plate through a bolt, the valve rod is connected with the butterfly plate through a pin, the four-eccentric butterfly valve is characterized in that a sealing surface on the valve body is a perfect circle sealing surface, the eccentricity e between the central line of the valve rod and the central line of the sealing surface is a first eccentricity, the eccentricity b between the central line of the valve rod and the central line of a butterfly valve channel is a second eccentricity, an included angle α formed between the central line of a cone formed by the sealing surface of the sealing ring and the central line of the butterfly valve channel is a third eccentricity, the length of a short shaft of an elliptic sealing surface in the cone body is.