JPH05240359A - Butterfly valve - Google Patents

Abstract

PURPOSE: To facilitate assembly and to prevent wear of a valve seat by providing a valve disk freely rotatable around an axis in a valve body provided with a detachable valve seat comprising a metal element and a polymeric element, and fastening the valve disk detachably to the axis with a special pin structure. CONSTITUTION: The butterfly valve has a valve body 1 with a valve disk 2 rotatably attached to the body via an axis 3 having a shoulder 4, and the valve disk 2 and the axis 3 are coupled via a rectangular pin 6 having a reduced height portion 10 which engages with the valve disk 2 and the axis 3 across a groove formed at a portion corresponding to the valve disk 2 and the axis 3 by fixing a retainer 11 on the valve body 1 to prevent axial displacement of the axis 3. A valve seat comprising a metal element 15 and a second element 16 made of a polymeric material retained to the valve body 1 by screws 14 through a retainer 13 is provided, the metal element 15 having a radial flange 17, a radial arm with convolution 18 and a seat end 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a butterfly valve, and more particularly to a connection between a valve member and a shaft of a butterfly valve and a valve seat and a stop mechanism of the butterfly valve.

[0002]

BACKGROUND OF THE INVENTION Many butterfly valves consist of a shaft-to-valve member connection using bolts located in the bore through the article and shaft.

[0003]

A problem associated with this configuration is the high stress on the bolts that wears and eventually breaks in the initial actuation of the disc when it is fitted to or lifted from the seat.

It is an object of the present invention to provide a butterfly valve that can withstand high stress on the bolt.

[0005]

According to the invention, a connection between members is proposed, one member penetrating the other,
And with this layout, each member forms a haspline into which the kota pin is introduced, and then leaves the pin held by the internal member in the other member, thus fixing the pin in the member. The two members can then be unaligned to join them together.

In the preferred embodiment of the present invention, the two members are the shaft and disc shaped valve members of a butterfly valve.
The axial spline is shorter than the valve portion spline and is the same length as the pin. The pin has a portion with a low height and the height of this portion is equal to the depth of the axial spline. The valve member spline is longer than the axial spline and the sum of the depths of both splines is equal to the pin height. The pin has a groove that allows the pin to be lifted to remove it from the spline when it is aligned, for example by a screwdriver. The shaft is stepped at one end to limit spline misalignment due to movement of the shaft within the valve member, and holds the shaft in this position relative to the valve portion and avoids access to the end of the shaft. The end plate is formed for this purpose.

The present invention also relates to a butterfly valve seat.

Such a seat is arranged between the disc-shaped valve member and the valve body, and many known examples already exist.

According to the invention, the valve seat is provided in a butterfly valve which can include a novel combination of the following features.

(A) The seat is made of metal.

(B) The seat projects from the valve body or the disk on the valve closing member.

(C) The seat has an outer side projecting radially from the disc.

(D) The seat has a spiral which is joined to the portion protruding in the radial direction.

(E) The seat has a seat tip joined to the spiral.

(F) The seat has a support tip connected to the seat tip.

The (g) metal is Inconel 718®.

The (h) locus is a polymer, such as P. T. F.
E. Made from fluorine plastic such as.

(I) The seat includes a locking portion, a neck portion and a protrusion from the seat.

The (j) seat has metal and polymerized portions adjacent to each other along the entire surface.

In accordance with the present invention, seats are provided for butterfly valves that include metal members formed to contact along their outer surface lengths and members made of synthetic plastic material, the metal portions being the valve. A swirl for greater flexibility with a flange that can be connected to the body or the valve disc, a seat tip made to make a hermetically sealed contact with the valve disc or the valve disc, and from the valve disc And a support tip adapted to serve as a stopper for the seat of the valve disc or valve disc under special condition pressure.

The present invention also relates to a stop mechanism for a butterfly valve.

In such a type of valve, the valve member guarantees as much as possible that it is correctly oriented within the valve body when it is in the closed position, ie at a right angle to the flow axis of the valve. There is a need to. Valves are known in which a stop is formed outside the valve on the shaft on which the valve member is mounted, but this device suffers from a lack of accuracy because the shaft may be twisted between the stopper and the valve member. Further, there is known a valve in which a stopper is formed inside the valve body that comes into contact with the periphery of the valve member when the valve member is in the closed position, but this device also lacks accuracy because the shaft bends due to pressure. And the member tends to pivot about the stopper, rather than about the shaft, resulting in uneven wear of the valve seat. One aspect of the invention is to mitigate these problems.

According to the invention, between the valve body and a first position in which the valve body rotates and which stops the flow of fluid through the valve, and a second position in which fluid can flow through the valve. In a butterfly valve, each stopper comprises a valve member arranged to move with respect to the valve member and means for avoiding movement of the valve member beyond the fully open position formed by the stopper on the valve body and the stopper on the valve member. Have two stop surfaces that act to contact and position themselves with the other two stop surfaces.

In the preferred embodiment of the present invention, the means for avoiding movement is formed by the stopper of the valve body and the stopper of the valve member. Each stopper has two stopper surfaces that operate to contact the two stoppers on the other stopper, respectively. One pair of stop surfaces contacts the valve member in the fully closed position and the other pair contacts the valve member in the fully open position. The first stopper pair contacts the plane of the front surface of the valve member at a right angle. The other pair touches the front plane at 45 °.

[0025]

The present invention will be described below with reference to the embodiments shown in the accompanying drawings.

Referring to the figures, the butterfly valve has a valve body 1 mounted on a shaft 3 for rotation of a disc-shaped valve member 2. The shaft 3 passes through the holes of the valve body 1 and the valve member 2. The shaft 3 is provided at its upper end with a stepped portion 4 arranged in the attached portion 5 of the inner diameter of the valve body 1. The valve member 2 and the shaft 3 introduced into the valve member 2 are specially shaped so that an interconnection between the valve member 2 and the shaft 3 can be made. The groove on the shaft 3 is designated by 7 and the groove on the valve member 2 is designated by 8.

The rectangular pin 6 having a constant thickness has a height corresponding to the depth of the groove 7 of the shaft 3 as well as the depth of the open groove 8 of the valve member 2. The pin 6 has in its longitudinal direction a reduced height 10 which corresponds to the height of the groove 7 of the shaft 3.
A groove 9 for screwing is formed at the end of the pin 6 so as to cover the entire width thereof. The groove 7 of the shaft 3 is formed with a length corresponding to the length of the pin 6 at a depth corresponding to the height reduced by 1/3. The spline groove 8 formed in the back surface portion of the valve member 2 runs through a hole corresponding to the shaft 3. The length of the groove 8 is approximately 1/3 longer than the length of the pin 6.

The valve is assembled as follows. A disc-shaped valve member 2 is arranged in the main body of the valve body 1. Axis 3 is the valve body 1
The spline groove 7 of the shaft 3 through the hole below the valve member 2
Introduce into the through hole until visible through the spline groove. The pin 6 is introduced into the valve member 2 and within the groove of the disc-shaped valve member 2 and the shaft 3 the part of the pin 6 with a reduced height 10 is visible towards the final mounting position of the shaft 3. After introducing the pin 6, the shaft 3 is pushed to its final position, and the pin 6 moves upwards in the inner diameter of the valve member until the stepped portion 10 of the pin 6 contacts the end of the groove 8 of the disc-shaped valve member 2. Pull. The lower end of the shaft 3 is held by a retainer 11 on the shaft to avoid axial movement of the shaft 3 and holds the pin 6 in place. To remove the shaft 3 and the valve member 2, the shaft retainer 11 is first removed. The shaft 3 and then the pin 6 are pushed down until they can no longer be seen in the spline groove 8, leaving an uncovered screwdriver groove at the lower end of the pin 6. By placing the instrument 9 in the groove, the pin can be raised and removed from the grooves 7 and 8 of the shaft and disc shaped valve member.
The shaft 3 is removed through the lower hole in the valve body.

The valve is formed by a valve body 1 which forms a main member 12 of the valve in which a valve closing member formed by a rotatable disc 2 is arranged. The valve seat is arranged in the valve body 1 between the body and the closing part 2 and is held in place by a retainer 13 on the seat which is joined to the valve body 1 by means of screws 14. A sealing washer 14 a is arranged between the retainer 13 and the valve body 1. The valve seat has a complicated structure. The structure is mainly a metal member 1.
5 and a seat having a second member 16 of polymeric material. Polymeric materials provide a primary seal, and metals provide a secondary seal when the primary seal fails due to excessive temperature, friction, etc. Each member can be used independently with minor modifications to the retainer and / or body tools.

The appearance of the metal seat can be decomposed into four different geometrical parts, each of which has the function of being considered identical, each of which, for example, the radial flange 1
7, having a radial arm 18 with a spiral, a seat tip and a support tip 20. The functions of these parts are as follows.

Radial Flange This portion is radial to the center of the valve 12 and projects from the outer diameter of the seat at the beginning of the radial spiral. This portion has a flat surface fit between the seat 13 and the body 1 through which a suitable number of retaining screws 14 extend to lock the seat 15 to the body. The seat retainer 13 and the hollow joint 14 in the body 1 are attached to both sides of the seat 15 so as to avoid leakage to the atmosphere. When mounted on the valve, this radial flange also
Help to hold and thus complete the locking chamber for this seat.

Radial Arm with Spirals This part is generally radial with a single spiral which begins at the beginning of the bend just inside the radial flange 17 and projects in the opposite direction to the seat retainer. This simple swirl 1
8 performs many important functions.

(A) It provides support and soft excitation for the polymer locus 16 whose appearance exactly matches this surface. (The polymer is usually a fluoroplastic, for example PTF, which has a limited memory and resistance to permanent deformation. A metal seat with the appearance described is made from a material such as Inconel 718. , It can serve to support and excite the polymer under all normal pressure / temperature conditions of use in the valve.) (B) It mechanically holds the polymer seat 16 in place.

(C) It creates a bending displacement point for the radial arm 17, thus increasing the reaction capacity of the seat.

Seat Tip 19 The seat tip 19 is formed around the closing member of the disc-shaped valve member 2 at the end of a generally convex surface starting at the center of the vertical curvature of the spherical surface of the seat. This convex surface begins at the outer end of the radial arm.

When the disc-shaped valve member 2 moves to the closed position, its seat edge portion thus makes tangential contact with the tip of the seat,
And the obstruction formed between the two seating surfaces has optimum characteristics regarding the sealing and rotational forces of the valve.

Support Tip The support tip 20 begins at a center of flexion that is substantially perpendicular to the tilt angle of the seat retainer (indicated by 21), and thus is generally convex with a bend that is opposite to the seat tip described above. It is formed in the shape of a spiral. This tilt 2 on the seat retainer 13
1 is a metal seat 1 when the disc-shaped valve member 2 is in the closed position
At the point of contact with 5, an angle of about 15 ° is formed with the tangent line drawn out on the spherical surface of the disc-shaped valve member 2.

In its free state, the support tip 20 does not come into contact with the seat retainer tilt angle 21, but an increasing seat load is generated by closing the disc-shaped valve member 2.
The support tip 20 is brought into contact with the tilt angle 21, thus increasing the rigidity and closing force of the seat 15. An increase in the closing load raises the support tip to the seat retainer ramp 21 and thus maintains the closing force.

Description of the Flexible Seat The flexible seat 16 is a round ring made of polymeric material, held in a hollow 22 having a generally square portion, held in the body and held in the hollow by a metal seat 15. is there.

The radial surface on the stacking seat 16 corresponds exactly to the surface which coincides with the metal seat 15, the other radial surface for forming the inner seat projection 23 achieved by the beveled surface. It is flat corresponding to the reduced part and its outer half.

This beveled surface is opposite the hollow formed by the spiral on the other surface, thus effectively dividing the seat into an outer locking portion 14 and an inner closing portion 23. The neck portion 24, with its smaller portion, can be softened by the seat projections by the action of closing forces and / or pipeline pressure. The inner shaft of the seat is convex with dimensions such that when in the closed position the disc-shaped valve member 2 forms a block on the spherical periphery of the seat.

Method of operation a) The pressure exerted on the side of the valve corresponding to the seat cage means that the reflecting action of the disc-shaped valve member 2 takes place axially with respect to the seat cage, thus It seeks to reduce the interference between the members 15 and 16 and the periphery of the seat of the disc-shaped valve member 2. Thus, the arrangement of seat members 15 and 16 must be capable of axial offsetting to compensate for this possible disc-shaped valve member movement. The fluid is first found in the metal seat and applies an axial force to the radial force with the spiral 20, increasing the closing force between the seat tip 19 and the spherical periphery of the disc-shaped valve member. Radial arm 18
Axial displacement of the flexible seat 16 also results from the close contact between the two seat components. Flexible seat 16
This offset of the shaft also causes the seat projection 23 to pivot about the neck portion 24, thus increasing interference with the spherical surface of the disc.
Therefore, when applying pressure in this direction both the metal and the flexible seat operate in a way that is excited under pressure.
The increase in pressure therefore results in an increase in closing pressure in both seats.

B) The pressure applied from the side of the valve corresponding to the main body (the side of the shaft of the disc-shaped valve member 2) takes the displacement of the disc-shaped valve member in the substantially axial direction and causes the seat retainer 13 to move. Moving towards the periphery of the disc and the two seat members 15 and 1
Increase the block between 6 The pressure also acts in this case on the first flexible seat 16 which is held by the metal seat 15 which excites it. The metal seat imparts elasticity and excitation to the flexible seat 16, effectively allowing the transition temperature and pressure. In case of failure or destruction of the flexible seat 16,
The pressure then acts directly on the metal seat 15 and moves it axially, causing the radial arm with the spiral to move closer to the cage seat. At the same time, the supporting tip 20 rises due to the inclination angle of the cage on the seat and maintains a closing force between the seat tip and the periphery of the spherical seat of the disc 21.

4 to 7, the butterfly valve is formed by a valve body 1 on which a valve member 2 is arranged and which can rotate. The valve member 2 is attached to a shaft 3 which is in turn attached to the valve body. Both the valve member 2 and the valve body 1 have stoppers 26 and 27. These stoppers cooperate in two different valve positions, a fully closed position (shown in Figure 4) and a fully open position (shown in Figure 5). Both stoppers have complementary surfaces that form contact surfaces at both positions. Thus faces 28 and 29 join when the valve is closed and faces 30 and 31 join when it is open.

Stopper 26 is shown in more detail in FIG. 6 and stop 27 is shown in more detail in FIG. FIG. 6 shows the valve member 2 from the rear. The valve member has a hole 2 projecting downward from the upper side where a shaft 3 (not shown) is arranged.
8a is formed. At one end of the valve hole, the surrounding material is made to form two stop surfaces 28 and 30. The stop surface 28 is 90 degrees from
And the stop surface 30 is 45 degrees from the front of the valve member 2.
°.

FIG. 7 shows the formation of stop surfaces 29 and 30 of the valve body. This formation has a projection 32 surrounding an opening 33 through which the shaft 3 (not shown) runs. Stop surface 2
9 is parallel to the front face of the valve member 2 and the stop face 3
1 forms an angle of 45 ° with this front face when the valve member is in the fully open position.

With the device described above, the valve member 2 is held tight when the valve is in the closed position and its angular offset is reduced. Due to the closing of the valve and the application of pressure in both directions, the valve member 2 moves linearly in relation to the flow and maintains a uniform deviation in and out of the valve body 1. In this way, there is a reduction in the angular offset produced by the eccentrically mounted valve member 2 having areas of non-uniform pressure, and non-uniform wear on the seat is eliminated. The presence of the open stopper means that the valve member will not open further than the fully open position.

The above embodiments have been described by way of example only and many variations are possible without departing from the scope of the invention.

[0049]

Since the present invention has the above-described structure, high stress does not occur in the bolt and the valve seat is not unevenly worn.

[Brief description of drawings]

1 is a longitudinal side view of a partially assembled butterfly valve according to the present invention. FIG.

2 is a longitudinal side view of the valve of FIG. 1 fully assembled.

FIG. 3 is a sectional view showing a part of a butterfly valve according to the present invention.

FIG. 4 is a cross-sectional plan view of the butterfly valve shown in a closed position.

5 is a cross-sectional plan view of the butterfly valve of FIG. 4 shown in an open position.

6 is a perspective view of a portion of the valve of FIGS. 4 and 5. FIG.

FIG. 7 is a perspective view showing a part of the valve.

[Explanation of symbols]

 1 valve body 2 valve member 3 axis 4 stepped portion 6 pin 13 seat 15 metal member 16 second member (flexible member) 17 radial flange 18 radial arm 19 seat tip 20 support tip 26 stopper 27 stopper 28 stop surface 29 Stop surface 30 Stop surface 31 Stop surface

Claims (21)

[Claims] 1. A valve body, arranged to move between a first position, which rotates within the valve body and stops flow of fluid therethrough, and a second position, where fluid can flow through the valve. And a means for avoiding movement of the valve member beyond the fully open position formed by the stopper on the valve body and the stopper on the valve member, each stopper including the other two
Acts to contact two stop surfaces and position them themselves 2
One of the valve members has a stop surface, the valve has a connection between the valve members, and each valve member holds the pin within the valve member to connect the two valve members, one of the valve members introduces the pin. To be contacted along a portion of its outer surface, formed by a spline that can be aligned to allow and then unaligned to hold the pin with the inner member in the other valve member. A formed metal member and a valve seat formed of a synthetic plastic material to pass through the other valve member and have a flange that allows the metal portion to be connected to the valve body or disc, A swirl for flexibility, a seat tip to make a hermetically sealed contact with the valve disc or valve disc, and to support the valve disc or valve disc seat under special conditions of load on the valve disc. Made with a support tip made Butterfly valve, wherein the door. 2. The butterfly valve according to claim 1, wherein the pair of stop surfaces on the valve body and the valve member respectively contact the valve in the fully closed position. 3. The butterfly valve according to claim 1, wherein the pair of stop surfaces on the valve body and the valve member respectively come into contact with the valve in the fully open position. 4. The butterfly valve of claim 2, wherein the pair of stop surfaces terminate at a right angle to the plane of the front surface of the valve member. 5. A butterfly valve according to claim 3, wherein the pair of stop surfaces contacting each other in the fully open position of the valve are joined in a plane at 45 ° to the plane of the front surface of the valve member. 6. A valve member is retained on an axis running through the opening in the valve body, and a stop on the valve body is formed by a protrusion on the valve body surrounding the opening. The butterfly valve according to any one of 1 to 5. 7. The valve member is retained on an axis running through the opening in the valve member, and the stopper on the valve member includes a shape on the valve member surrounding the opening. The butterfly valve according to any one of 5 above. 8. The butterfly valve according to claim 1, wherein the spline of the valve member is shorter than the spline of the other valve member. 9. Butterfly valve according to claim 1 or claim 8, characterized in that the pin has a portion with a low height, which height is equal to the depth of the spline of one of the valve members. .. 10. The butterfly valve of claim 1, wherein the spline of the other valve body is longer than the one spline and the sum of the depths of both splines is equal to the pin height. 11. The method of claim 1, 8, 9 having grooves to allow the pins to be lifted so that the pins are removed from the splines when the splines are aligned.
11. The butterfly valve according to any one of items 10 and 10. 12. The valve member is stepped at one end to limit spline misalignment due to movement relative to the valve member, and the plate retains position relative to the valve member at one end.
It is formed so as to prevent the valve member from approaching the one end.
The butterfly valve according to any one of 1. 13. A valve member according to claim 1, wherein one valve member is a shaft and the other valve member is a valve closing member in the form of a disc for a butterfly valve.
The butterfly valve according to any one of 2 above. 14. The butterfly valve according to claim 1, wherein the valve member made of a synthetic plastic material is a polymer. 15. The butterfly valve according to claim 14, wherein the polymer is a fluorine plastic. 16. The butterfly valve according to claim 15, wherein the fluorine plastic is polytetrafluoroethylene (PTFE). 17. The butterfly valve according to claim 1, wherein the seat and the supporting tip are adjacent to each other. 18. The butterfly valve as claimed in claim 1, wherein the valve member made of synthetic plastic forms a projection of the seat. 19. A butterfly valve according to claim 1, wherein the valve member of synthetic plastics forms a neck about which the projection can pivot. 20. A metal valve member projecting radially from a valve disc and held between a valve body and a seat retainer. Butterfly valve described in. 21. The butterfly valve according to claim 20, wherein the valve member made of a synthetic plastic material includes a locking portion held between the metal seat and the valve body.