CN100520132C - Non-abrasion hard-sealing butterfly valve - Google Patents

Abstract

The invention relates to a wear-free hard-sealed butterfly valve, which includes a valve body, a valve rod, a butterfly plate and a valve seat, and is characterized in that the valve seat is a movable valve seat that can move axially along the inner wall of the valve body; one side of the valve body There is a side body; a sealing ring is installed between the valve seat, the valve body and the side body; the seal is fastened on the butterfly plate frame; there is a moving fit gap between the inner and outer sides of the valve seat and the valve body and the side body , there is a spring between the outer end surface of the valve seat and the side body, and the inner end surface is connected with the valve stem through a push rod; There is a long keyway in the middle of the valve stem, and there are upper and lower keys respectively fixed on the upper and lower connecting seats, and the upper and lower connecting seats are respectively fastened on the butterfly plate; the push rod It includes upper and lower push rods, one end of which is equipped with a roller, one end of the lower push rod is embedded in the lower curved groove, and can slide, and the other end is hinged with the inner end surface of the movable valve seat; the upper push rod and the lower push rod are installed symmetrically ; There is a single eccentric structure between the disc rotation axis and the sealing plane.

Description

A wear-free hard seal butterfly valve

technical field

The invention relates to a valve, in particular to a wear-free hard-sealed butterfly valve. The international patent classification number is intended to be Int.Cl.F16K1/22 (2006.01).

Background technique

Existing hard seal butterfly valves generally include a valve body, a valve stem, a butterfly plate and a valve seat. The inner circle of the valve seat and the outer circle of the seal form a sealing pair. When the valve is closed, relying on the radial compression of the butterfly plate and the thrust of the positive medium, the sealing ring is elastically deformed to achieve an interference fit seal. Due to structural reasons, when the butterfly valve is opened and closed, there is always friction between the sealing pairs, which increases the torque of the opening and closing valve and slows down the opening and closing speed. The inevitable frequent opening and closing will cause accelerated wear of the sealing surface and improve the sealing performance. drop, eventually causing valve (leakage) damage. For this reason, someone has studied "a wear-free butterfly valve" (see Chinese patent ZL200420010685.X). The valve body has a built-in valve seat that matches the butterfly plate, and a melting pool is arranged on the inner and outer end faces of the valve seat. When closing, the valve seat is detached from the butterfly plate under the action of the pressure relief of the outer molten pool and the pressurization of the inner molten pool, the opening and closing torque is greatly reduced, and no friction between the sealing pairs can be realized. But this kind of butterfly valve still has the following disadvantages: 1. The structural accuracy related to the molten pool is actually very high, the processing is difficult, and the product cost is greatly increased; 2. The molten pool itself also needs to be sealed, and the sealing effect is difficult. Guarantee, affect or reduce its pressure charging and pressure relief performance, and the sealing problem of the butterfly valve has not been completely solved; 3. The valve drive cannot be driven by manual and electric modes at the same time, and the applicable area is narrow and inconvenient to use.

Contents of the invention

Aiming at the deficiencies of the prior art, the technical problem to be solved by the present invention is to design a wear-free hard seal butterfly valve. The valve seat of the butterfly valve can move along the axial direction of the valve body, there is no friction between the sealing pairs, the operating torque is low, the opening and closing speed is fast, and the impact effect is small, the service life is long, the driving mode is diverse, and the manufacturing process is simple and the cost is low.

The technical solution of the present invention to solve the technical problem is to design a wear-free hard-sealed butterfly valve, which includes a valve body, a valve stem, a butterfly plate and a valve seat, and is characterized in that the valve seat can move along the inner wall of the valve. A movable valve seat with an annular structure for axial movement is set in the valve body and cooperates with the seal installed on the edge of the butterfly plate to form a sealing pair; one side of the valve body is fixed with a side body ; Sealing rings are installed between the movable valve seat and the valve body and side body; Between the pressure plates of the seals, the outer circle exceeds the outer edge of the butterfly plate frame; there is a moving fit gap between the inner and outer sides of the valve seat and the valve body and side body, and the outer circle of the movable valve seat A spring is installed between the end face and the side body, and the inner end face of the valve seat is connected with the valve stem through a push rod; a spring hole is opened on the inner end face of the side body, and the spring is installed in the spring hole; the valve stem The upper and lower ends of the upper and lower ends are respectively provided with an upper curved groove and a lower curved groove. The upper curved groove and the lower curved groove are respectively composed of a section of inclined groove and a section of circular arc groove perpendicular to the center line of the valve stem. There is also a long keyway in the middle of the rod, and an upper sliding key and a lower key that can slide along it are installed on the long keyway. The upper sliding key and the lower key are fixedly connected to the upper connecting seat and the lower connecting seat respectively. The connecting seats are respectively fastened on the butterfly plate by bolts; the push rods include symmetrically arranged upper push rods and lower push rods, and cylindrical rollers are installed at one end of the upper push rods and lower push rods, and the lower push rods One end equipped with a cylindrical roller is embedded in the lower curved groove at the lower end of the valve stem, and can slide along the lower curved groove, and the other end is hinged with the inner end surface of the movable valve seat; the upper push rod and The lower push rod is symmetrically installed in the upper curved groove on the upper end of the valve stem, and can slide along the upper curved groove; there is an axial eccentricity between the rotation axis of the butterfly plate and the sealing pair plane, which is a single eccentric structure.

Compared with the prior art, the beneficial effects of the butterfly valve of the present invention are:

1. Improve performance. The butterfly valve of the present invention improves the traditional fixed valve seat into a movable valve seat that can move axially along the center line of the valve body. When the valve is opened, the valve stem moves linearly first, and the valve seat is first separated from the seal by the push rod. , and then the valve stem rotates to open the butterfly plate through the action of the feather key and the connecting seat. This unique design avoids the friction between the sealing pairs when the butterfly plate rotates, and when the butterfly plate is opened, most of the medium pressure on both sides of the butterfly plate has been removed, so the opening and closing torque is greatly reduced, which is only for ordinary butterfly valves. About 10% of the driving device and actuator models can be reduced accordingly, thereby reducing costs, saving energy, and increasing the opening and closing speed.

2. Life extension. When the butterfly valve of the present invention opens the butterfly plate, because the sealing surface is disengaged first, the pressure difference on both sides of the butterfly plate is reduced, so the impact of the fluid medium on the opening of the butterfly plate is reduced, and the operating noise is also reduced, so the impact fatigue resistance of the butterfly valve is reduced. The destructive ability is greatly improved, which can increase the service life of the valve from the current thousands of times to hundreds of thousands of times.

3. Wide applicability. The drive mode of the butterfly valve of the present invention is various, and can be driven by electric, manual, hydraulic or pneumatic modes, and is very convenient to use.

4. Good sealing performance. When the butterfly valve of the present invention is closed, the valve stem pushes the valve seat to press against the sealing member along the central axis of the butterfly plate through the push rod, and the elastic force of the spring also assists in pressing the sealing surface to ensure good sealing performance.

Description of drawings

Fig. 1 is a schematic front view of an overall structure of an embodiment of a butterfly valve of the present invention;

Fig. 2 is a schematic cross-sectional view of A-A in Fig. 1 of an embodiment of the butterfly valve of the present invention;

Fig. 3 is a kind of embodiment of butterfly valve of the present invention Fig. 2 partial enlarged schematic diagram of I place;

Fig. 4 is the B-B sectional schematic diagram in Fig. 1 of a kind of embodiment of butterfly valve of the present invention;

Fig. 5 is a partially enlarged schematic diagram of II in Fig. 4 of an embodiment of the butterfly valve of the present invention;

Fig. 6 is a schematic rear view of the stem structure in Fig. 1 of an embodiment of the butterfly valve of the present invention;

Fig. 7 is an enlarged schematic diagram of part III in Fig. 6 of an embodiment of the butterfly valve of the present invention;

Fig. 8 is a schematic sectional view of C-C in Fig. 6 of an embodiment of the butterfly valve of the present invention.

Detailed ways

Further describe the present invention below in conjunction with embodiment and accompanying drawing thereof, but it does not limit the claims of the present invention.

The embodiment of a wear-free hard-sealed butterfly valve (hereinafter referred to as butterfly valve, see Figures 1-8) designed by the present invention includes a valve body 5, a valve stem 6, a butterfly plate 17 and a valve seat 19, which is characterized in that the valve seat 19 is a movable valve seat 19 with a circular structure that can move axially along the inner wall of the valve body 5. It is arranged in the valve body 5. When moving axially, the sealing surface of the movable valve seat 19 is perpendicular to the butterfly plate. The central axis of 17 cooperates with the seal 18 installed on the edge of the butterfly plate 17 to form the sealing pair of the butterfly valve; a side body 13 is installed on one side of the valve body 5 by screw fastening; the movable valve seat 19, the valve body 5 and the side body 13 are installed with a sealing ring 20; the sealing member 18 is fastened to the butterfly plate frame 17.1 by bolts using the sealing member pressure plate 17.2, which can be easily installed and disassembled. The sealing member 18 It is sandwiched between the butterfly plate frame 17.1 and the sealing member pressure plate 17.2, and its outer circle exceeds the outer edge of the butterfly plate frame 17.1; the inner and outer sides of the valve seat 19 and the valve body 5 and the side body 13 are left There is a moving fit gap, and a spring 14 is installed between the outer end surface of the movable valve seat 19 and the side body 13, and the inner end surface of the valve seat 19 is connected with the valve stem 6 through a push rod 15; The inner end surface is provided with a spring hole 13.1, and a spring 14 is installed in the spring hole 13.1; the upper and lower ends of the valve stem 6 are respectively provided with curved grooves 10 (10.1 and 10.2), and the curved groove at the upper end of the valve stem 6 is called an upper curved groove. (marked as 10.1 in Figure 6-8), the curved groove at the lower end of the valve stem 6 is called the lower curved groove (marked as 10.2 in Figure 6-8); The upper arc groove 10.12 on the centerline of the valve stem 6 is smoothly connected, and the lower curved groove 10.2 is also composed of a section of lower chute 10.21 and a section of lower arc groove 10.22 perpendicular to the centerline of the valve stem 6. The upper arc groove 10.22 is smoothly connected. The central angles of the arc groove 10.12 and the lower arc groove 10.22 are both 90 degrees (see Figure 6-8); the middle part of the valve stem 6 has a long keyway 9, and the long keyway 9 is equipped with an upper keyway that can slide along it. The sliding key 8 and the sliding key 8', the upper sliding key 8 and the sliding key 8' are fixedly connected to the upper connecting seat 7 and the lower connecting seat 7' respectively, and the upper connecting seat 7 and the lower connecting seat 7' are respectively fastened to the On the butterfly plate 17; the push rod 15 includes a symmetrically arranged upper push rod 15.1 and a lower push rod 15.2, and one end of the upper push rod 15.1 and the lower push rod 15.2 is equipped with a cylindrical roller 22, and the lower push rod 15.2 One end equipped with cylindrical roller 22 is embedded in the lower curved groove 10.2 of the lower end of the valve rod 6, and can slide along the lower curved groove 10.2 (see Figures 4 and 5), and the other end is connected to the movable valve seat. The inner end surface of 19 is hinged; the upper push rod 15.1 and the lower push rod 15.2 are symmetrically installed in the upper curved groove 10.1 of the upper end of the valve stem 6, and can slide along the upper curved groove 10.1. There is an axial eccentricity between the rotation axis of the butterfly plate 17 (ie, the centerline of the valve stem) and the sealing sub-plane, which is a conventional single eccentric structure.

A further feature of the present invention is that the inner circular surface of the movable valve seat 19 of the annular structure is a right conical surface. The manufacturing process is simple, the cost is low, and the work is reliable. The present invention is provided with a sealing ring 20 (as shown in Figures 2 and 3) on the bonding surface of the valve seat 19 and the valve body 5 and the side body 13, and the sealing ring 20 includes several sets of sealing rings 20.1 of different sizes. , sealing ring 20.2 and sealing ring 20.3, they can ensure that when the valve seat 19 moves, the butterfly valve has good sealing performance. The outer circular surface of the embodiment of the sealing member 18 adopts a positive conical surface with the same taper angle as the inner circular surface of the movable valve seat 19 . The unique structure of the movable valve seat 19 can realize the frictionless opening and closing of the sealing surface, thereby greatly reducing the opening and closing torque of the butterfly valve, improving the service life of the butterfly valve and increasing the opening and closing speed at the same time.

There is a movement fit gap between the inner and outer surfaces of the movable valve seat 19 of the present invention, the outer surface of the valve body 5 and the inner surface of the side body 13, so as to ensure that the valve is sealed when the valve is opened and closed. The surface can be completely disengaged and sealed (see Figures 2 and 3);

The left and right ends of the valve body 5 of the present invention are provided with flanges perpendicular to the centerline of the valve body 5, and the upper and lower ends of the valve body 5 are provided with an upper valve stem hole and a lower valve stem hole through which the valve stem 6 passes. The upper and lower sides of the butterfly plate 17 are respectively provided with an upper connecting seat 7 and a lower connecting seat 7'; the valve stem 6 passes through the upper valve stem hole and the upper connecting seat 7 from above the valve body 5 , the lower connecting seat 7' and the lower valve stem hole, the valve stem 6 and the upper connecting seat 7 and the lower connecting seat 7' are fixedly connected with the upper sliding key 8 and the lower connecting seat 8' in the circumferential direction; the lower valve of the valve body 5 The outer end of the rod hole is provided with a lower pipe sleeve 11, on which a lower flange is fixedly installed, and the lower flange is connected with the closed lower cover 12 with bolts. The outer end of the upper valve stem hole of the valve body 5 is provided with an upper pipe sleeve 4, An upper flange is fixedly installed on it, and a bracket 3 is installed with bolts on the upper flange, and the bracket 3 is connected with a driving device 1, and the driving device 1 is provided with a hand wheel 21 (see Fig. 1).

The upper part of the valve stem 6 of the present invention is provided with a stuffing box surrounding the outside of the valve stem 6, the stuffing box is filled with stuffing, and is provided with a sleeve and a gland 2 pressed on the stuffing (see Figure 1).

There is a certain distance between the rotation axis of the butterfly plate 17 of the present invention (that is, the centerline of the valve stem 6) and the sealing sub-plane (the cross section perpendicular to the sealing surface and the center axis of the valve body 5), and this distance is called axial eccentricity. The purpose of making the butterfly valve have a single eccentric structure is to make the push rod 15 device have a certain operating space (see FIG. 1 ).

The butterfly plate 17 of the present invention is provided with reinforcing ribs 16 to improve the strength and increase the service life.

The working principle of the butterfly valve of the present invention is: when the valve is opened, the valve rod 6 moves upward in a straight line under the action of the prior art structure (referring to Chinese patent CN00200523.9), and the push rod 15 moves downward along the curved groove 10, And drive the valve seat 19 to translate to the left along the central axis of the butterfly plate, and at the same time the spring 14 is compressed until the central axis of the cylindrical roller 22 coincides with the plane where the centerline of the arc groove of the curved groove 10 is located, so that the valve seat 19 Disengaged from the seal 18 for a certain distance, the pressure in the inner cavity of the valve is greatly reduced, and then the valve stem 6 rotates again, and through the action of the upper and lower keys 8, 8' and the upper and lower connecting seats 7, 7', Drive the butterfly plate 17 to rotate 90 degrees without friction to open the valve.

When the valve is closed, the valve stem 6 rotates, and through the action of the up and down keys 8, 8' and the up and down connecting seats 7, 7', the butterfly plate 17 is driven to reversely rotate 90 degrees without friction. At this time, the valve There is a certain distance between the seat 19 and the seal 18, and the central axes of the two are in the coincident position; then the valve stem 6 moves down in a straight line, and the push rod 15 moves upward along the curved groove 10, and drives the valve seat 19 along the center of the butterfly plate 17. The axial direction translates to the right and presses against the sealing member 18, and the spring 14 also pushes the valve seat 19 to move to the right until the valve seat 19 and the sealing member 18 are compressed, the sealing surface is completely sealed, and the valve is closed.

What is not mentioned in the present invention is applicable to the prior art. At the same time, different specific implementation modes produced by referring to the prior art are all specific implementation modes of the present invention.

"Up", "Down", "Left", "Right", "Inside" and "Outside" used in the installation position or direction of the structure or parts of the butterfly valve of the present invention are based on the orientation of the given drawings As a basis, they are only for the convenience of expression, and are used to distinguish the relative positions of various components or directions, and do not represent the orientation of the butterfly valve of the present invention when it is used.

Claims (3)

1. A wear-free hard-sealed butterfly valve, which comprises a valve body, a valve stem, a butterfly plate and a valve seat, is characterized in that the valve seat is an annular structure that can move axially along the inner wall of the valve The valve seat is set in the valve body and cooperates with the seal installed on the edge of the butterfly plate to form a sealing pair; one side of the valve body is fixed with a side body; the movable valve seat and the valve A sealing ring is installed between the body and the side body; the seal is fastened to the butterfly plate frame by bolts using the seal pressure plate, and the seal is sandwiched between the butterfly plate frame and the seal pressure plate, and its outer circle exceeds the butterfly plate. The outer edge of the plate frame; there is a moving fit gap between the inner and outer sides of the valve seat and the valve body and the side body, and a spring is installed between the outer end surface of the movable valve seat and the side body , the inner end surface of the valve seat is connected with the valve stem through a push rod; the inner end surface of the side body is provided with a spring hole, and the spring is installed in the spring hole; the upper and lower ends of the valve stem are respectively provided with upper curved grooves and The lower curved groove, the upper curved groove and the lower curved groove are respectively composed of a section of inclined groove and a section of circular arc groove perpendicular to the center line of the valve stem, which are smoothly connected. There is also a long keyway in the middle of the valve stem. The upper and lower keys that can slide along it are installed, and the upper and lower keys are fixedly connected to the upper connecting seat and the lower connecting seat respectively, and the upper connecting seat and the lower connecting seat are respectively fastened to the butterfly plate by bolts The push rod includes a symmetrical upper push rod and a lower push rod, one end of the upper push rod and the lower push rod is equipped with a cylindrical roller, and one end of the lower push rod is equipped with a cylindrical roller embedded in the The lower curved groove at the lower end of the valve stem, and can slide along the lower curved groove, and the other end is hinged with the inner end surface of the movable valve seat; the upper push rod and the lower push rod are symmetrically installed on the upper end of the valve stem In the upper curved groove of the butterfly plate, and can slide along the upper curved groove; there is axial eccentricity between the rotation axis of the butterfly plate and the sealing pair plane, which is a single eccentric structure. 2. The wear-free hard-seal butterfly valve according to claim 1, characterized in that the inner circular surface of the movable valve seat of the annular structure is a positive conical surface; the outer circular surface of the seal is the same as The inner circular surface of the movable valve seat is a positive conical surface with the same cone angle. 3. The wear-free hard-sealed butterfly valve according to claim 1 or 2, characterized in that a reinforcing rib is provided on the butterfly plate.

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