CN105240545B - A kind of dual drive is without friction hard-sealing butterfly valve - Google Patents

Abstract

The invention discloses a double-drive frictionless hard-sealed butterfly valve. The butterfly valve includes a valve body, a valve stem, a butterfly plate and a driving device thereof. The driving device includes a handwheel and a handle, and is characterized in that the valve stem is provided with The ring-shaped structure of the upper valve stem sleeve and the lower valve stem sleeve, the central axis of the handle and the valve stem are coincident, and are connected with the valve stem with interference, and the hand wheel is connected with the upper valve stem sleeve by bolts, and the torque is transmitted to the upper and lower Stem sleeve; the upper and lower stem sleeves are respectively fixed with upper and lower sleeves, upper and lower cams with flat keys; the valve stem is connected with the connecting rod, and the valve stem and the butterfly plate are welded together; the valve stem The outer peripheral surface has an outer peripheral surface at an angle of 180 degrees with the flat key. On the inner peripheral surface of the connecting rod, an inner peripheral surface with the same diameter as the outer peripheral surface is provided. After assembly, the outer peripheral surface and the inner peripheral surface The positions of the faces correspond to each other; a spring is arranged in the inner peripheral face; the initial state of the spring is an incompletely compressed state, and the compression force is smaller than the impact force of the fluid medium.

Description

A dual-drive frictionless hard-sealed butterfly valve

technical field

The invention relates to a butterfly valve, in particular to a frictionless hard-sealed butterfly valve with double drives.

Background technique

The hard seal butterfly valve has the advantages of simple structure and convenient and quick opening and closing, so it is widely used in the switch control of low pressure pipeline medium. In the prior art, due to structural reasons, the sealing specific pressure between the sealing pairs is fixed. When the valve plate 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. Frequent opening and closing will easily cause the sealing surface to wear, the sealing performance will decrease, and eventually the valve will leak. The applicant's prior patent "a wear-free hard-sealed butterfly valve" (ZL200710150352.5) has solved this problem well: the valve seat is a movable valve seat that can move axially along the inner wall of the valve, and the outer surface of the valve seat is A spring is installed between the end face and the side body of the valve body. The inner end face is connected to the valve stem through a push rod. There are cylindrical rollers at one end of the upper and lower push rods. The child slides along the curved groove, the push rod pushes the valve seat to move, the sealing surface is disengaged, the opening and closing torque is greatly reduced, and the wear between the sealing pair of the butterfly plate and the valve seat is avoided, and then the valve stem rotates to drive the butterfly plate to rotate and open Butterfly valve. Although this wear-free butterfly valve reduces wear and greatly unloads the medium pressure, it still has the following disadvantages: 1. The structure and manufacturing process are more complicated and the cost is higher; 2. The valve stem is provided with curved grooves, and the valve stem The bearable strength is reduced; 3. The specific pressure of the sealing surface is not uniform enough.

Contents of the invention

Aiming at the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a double-drive frictionless hard-sealed butterfly valve, which can only be opened in the positive flow state, and the sealing specific pressure is uniform when closed, which can effectively improve the butterfly valve. sealing performance.

The double-drive frictionless hard-sealed butterfly valve (hereinafter referred to as the butterfly valve, see Figure 1-5) designed by the present invention includes a valve body, a valve stem, a butterfly plate and its driving device. The driving device includes two parts: a handwheel and a handle. It is characterized in that an upper valve stem sleeve and a lower valve stem sleeve with a circular structure are arranged outside the valve stem, the central axes of the handle and the valve stem coincide and are connected with the valve stem by interference, and the hand wheel is connected with the upper valve stem by bolts. The sleeve is connected to transmit torque to the upper and lower valve stem sleeves; the upper and lower valve stem sleeves are respectively fixed with an upper sleeve and a lower sleeve, an upper cam and a lower cam with a flat key; the middle part of the valve stem is passed through a flat key It is connected with the connecting rod, and the valve rod and the butterfly plate are welded together; the outer peripheral surface of the valve rod has an outer peripheral surface at an angle of 180 degrees with the flat key, and on the inner peripheral surface of the connecting rod, there is a The diameter of the inner peripheral surface is the same as that of the outer peripheral surface. After assembly, the outer peripheral surface on the valve stem corresponds to the position of the inner peripheral surface on the connecting rod. There is a spring inside the inner peripheral surface; the initial state of the spring is incompletely compressed. And the compression force of the spring compressed state is less than the impact force of the fluid medium; the axis line of the valve stem deviates from the center of the butterfly plate, which is a single eccentric structure.

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

1. Life extension. The butterfly valve of the present invention is controlled by two driving mechanisms, so that the sealing surface is disengaged first, and the butterfly plate rotates to open the butterfly valve, realizing the frictionless opening and closing of the butterfly valve; the disengagement of the sealing surface unloads the medium pressure, reducing the valve when opening and closing. The operating torque, so the impact of the fluid medium on the opening of the butterfly plate is reduced, so that the service life of the butterfly valve is increased from the current thousands of times to hundreds of thousands of times.

2. Good sealing performance. The butterfly valve of the present invention is provided with upper and lower cams in the middle of the valve stem. When the butterfly valve is closed, the plane contours of the upper and lower cams always press the butterfly plate, providing a mechanical wedging force for the butterfly plate and ensuring continuous tight sealing. , improve sealing performance.

3. Simple structure. Compared with other frictionless butterfly valves, the structure of the butterfly valve of the present invention is simpler, enhances the reliability of the butterfly valve, is easier to manufacture and reduces the cost.

Description of drawings

Fig. 1 is a schematic front view of the overall structure of an embodiment of a dual-drive frictionless hard-sealed butterfly valve of the present invention;

Fig. 2 is the A-A sectional structure schematic diagram in Fig. 1 of an embodiment of the double-drive frictionless hard-sealed butterfly valve of the present invention;

Fig. 3 is a full cross-sectional structural schematic diagram of an embodiment of a double-drive frictionless hard-sealed butterfly valve of the present invention after the handwheel is rotated 90 degrees;

Fig. 4 is the partial (I place in Fig. 2) enlarged structural representation of a kind of embodiment of dual-drive frictionless hard seal butterfly valve of the present invention;

Fig. 5 is a partial (II in Fig. 3 ) enlarged structural schematic diagram of an embodiment of a dual-drive frictionless hard-sealed butterfly valve of the present invention.

detailed description

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

The double-drive frictionless hard-sealed butterfly valve designed by the present invention (hereinafter referred to as the butterfly valve, see Figure 1-5) mainly includes a valve body 10, a valve stem 15, a butterfly plate 16 and its driving device, and is characterized in that the driving device It consists of two parts, the handwheel 7 and the handle 6, the handwheel 7 is connected with the upper valve stem sleeve 9 by bolts, the central axis of the handle 6 coincides with the valve stem 15, and is interferingly connected with the valve stem 15; the valve stem 15 is set outside There are an upper valve stem sleeve 9 and a lower valve stem sleeve 9', both of which are annular structures, and the upper valve stem sleeve 9 and the lower valve stem sleeve 9' are fixedly installed with an upper sleeve 3 and a lower sleeve 3 respectively ', the upper cam 11 and the lower cam 11'; the upper sleeve 1 and the lower sleeve 1' are respectively installed between the upper sleeve 3 and the lower sleeve 3' and the valve body 10, and the upper sleeve 1 and the lower shaft The shape of one end of the sleeve 1' is an arc shape.

The outer peripheral surface of the valve stem 15 has an outer peripheral surface at an angle of 180 degrees with the flat key. On the inner peripheral surface of the connecting rod 5, an inner peripheral hole with the same diameter as the outer peripheral hole is provided. After assembly, The outer peripheral surface on the valve stem 15 corresponds to the inner peripheral surface on the connecting rod 5, and a spring 12 is arranged in the inner peripheral surface (see Figure 4); the initial state of the spring 12 is an incompletely compressed state, and the spring compressed state The compressive force is less than the impact force of the fluid medium; the axis line of the valve stem 15 deviates from the center of the butterfly plate, which is a single eccentric structure.

A valve stem sleeve 21 is arranged between the handle 6 and the upper valve stem sleeve 9 of the butterfly valve of the present invention, the valve stem sleeve 21 has the effect of axial positioning, and can protect the valve stem 15 from wear; The upper valve stem sleeve 9 is fastened together with bolts, and the rotation of the hand wheel 6 directly drives the movement of the upper valve stem sleeve 9; a packing gland shaft sleeve 22 is also installed between the hand wheel 7 and the packing gland 8, and the packing gland shaft The sleeve 22 is used for axial positioning. The upper part of the upper valve stem cover 9 is provided with packing pads and asbestos fillers surrounding the outer side of the upper valve stem cover 9 and is provided with a packing gland 8 pressed on the packing, and the packing gland 8 is fastened to the valve body with hexagonal bolts. 10 on (see Figure 2).

In the butterfly valve of the present invention, in order to ensure the reliability of the action of the butterfly valve, the upper and lower parts of the valve rod 15 are provided with symmetrical upper bushing 1 and lower bushing 1', upper sleeve 3 and lower sleeve 3', and upper cam 11 and lower cam 11'. The valve stem 15 is provided with an upper valve stem sleeve 9 and a lower valve stem sleeve 9', which are all annular structures; the upper valve stem sleeve 9 and the lower valve stem sleeve 9' are respectively fixed and installed with flat keys There are upper sleeve 3 and lower sleeve 3', upper cam 11 and lower cam 11'. One end of the upper sleeve 3 and the lower sleeve 3' is a plane, and the upper and lower ends of the connecting piece 4 are fastened on the upper sleeve 3 and the lower sleeve 3' with screws 2, and the connecting piece 4 connects the upper valve stem. The movement of sleeve 9 is synchronized to the lower valve stem sleeve 9'; part of the contour surface of the upper cam 11 and lower cam 11' is a plane. When the butterfly valve is closed, the upper cam 11 and the lower cam 11' are parallel to each other, pressing the butterfly valve Plate 16; when the butterfly valve is opened, the upper cam 11 and the lower cam 11' rotate 90 degrees, and its plane profile loosens the pressed butterfly plate 16. An upper bushing 1 and a lower bushing 1' are respectively installed between the upper sleeve 3, the lower bushing 3' and the valve body 10, and the feature is that the upper bushing 1 and the lower bushing 1' Correspondingly, set it as a special structure, that is, one end of the shaft sleeve is arc-shaped (see Figure 1).

The middle part of the valve stem 15 is connected with the connecting rod 5 through a flat key 17 (see FIG. 4 ), and the valve stem 15 and the butterfly plate 16 are welded together. The spring 12 is initially in an incompletely compressed state, the impact force of the fluid medium is greater than the compression force of the spring 12, and the compression displacement of the spring 12 under the impact force of the medium is equal to the displacement of the butterfly plate 16 and the connecting rod 5, realizing The translation of the butterfly plate 16 and when the butterfly valve is opened, the elastic force of the spring 12 will resist the shaking of the butterfly plate 16 under the impact force of the medium, which ensures the reliability of the mechanism.

The flange of the valve body 10, the valve seat and the valve body itself are all cast. This design makes the processing simple and reduces the cost, and it is easy to do in actual production. The lower valve stem sleeve 9' is provided with a There is an asbestos filler surrounded on the outside of the valve stem 15, and an axle sleeve 13 pressed on the filler is arranged, and the valve body 10 is connected with a closed end cover 14 with bolts.

The double drive and upper and lower valve stem sleeves of the butterfly valve of the present invention have a unique structure. The driving of the handwheel 7 directly drives the upper valve stem sleeve 9 and the lower valve stem sleeve 9', and the upper valve stem sleeve 9 and the lower valve stem sleeve 9' transmits torque to the cam, and the impact force of the fluid medium makes the translation of the butterfly valve a small displacement (see Figure 5), and unloads. Rotate the handle 6 again, the valve rod 15 is consistent with the motion of the handle 6, and the valve rod 15 rotates and manipulates the connecting rod 5 to open the butterfly valve. Driving the upper and lower valve stem sleeves and valve stem separately makes the butterfly valve truly realize the "translation + rotation" action, realizes the frictionless opening and closing of the butterfly valve, greatly reduces the opening and closing torque of the butterfly valve, and improves the service life of the butterfly valve.

After the handwheel 7 of the butterfly valve of the present invention rotates 90 degrees, the impact force of the medium causes the butterfly plate 16 to translate for a small displacement (see FIG. 5 ). Both adopt conical surfaces, and the butterfly plate sealing ring 18 is fastened on the pressure ring 20 with screws 19. Under high temperature conditions, the multi-layer sealing ring is still a whole under the fastening of screws 19. The inclined cone sealing ring is processed by metal as a whole, and its elastic deformation is smaller than that of the asbestos plate gasket. It is mainly sealed by the torque thrust of the driving mechanism and the thrust of the medium. This method can achieve higher processing accuracy.

The butterfly valve of the present invention has a single eccentric structure (see Figures 2 and 3). The single eccentric structure means that there is a certain distance between the axis line of the valve rod 15 and the center of the butterfly plate. This distance is called axial eccentricity, which constitutes the single eccentric structure of the butterfly valve.

The working principle and process of the butterfly valve of the present invention are: when the butterfly valve is opened, the hand wheel 7 is first driven to rotate clockwise, and the upper valve stem sleeve 9 is driven to rotate, and the movement of the upper valve stem sleeve 9 is synchronized to the The lower valve stem sleeve 9', so that the upper and lower valve stem sleeves rotate at the same time, the handwheel 7 rotates 90 degrees, and the cams 11 and 11' connected to the upper and lower valve stem sleeves also rotate 90 degrees, so the cams 11 and 11' are loose The pressure of the butterfly plate 16 and the impact force of the fluid medium make the sealing surface of the butterfly valve (that is, the sealing surface composed of the valve seat sealing ring 10 and the butterfly plate sealing ring 18) separated by a short distance, and the pressure in the inner cavity of the valve body 10 Large unloading, and then drive the handle 6 to rotate clockwise, so that the valve rod 15 drives the connecting rod 5 and the butterfly plate 16 to rotate 90 degrees without friction, so that the butterfly valve is fully opened. When the butterfly valve is closed, the handle 6 drives the valve stem 15 to turn 90 degrees counterclockwise, the butterfly plate 16 and the connecting rod 5 turn 90 degrees under the drive of the valve stem 15, and they are in a closed state, and then turn the hand wheel 7 counterclockwise to move the valve up and down. The rod sleeve rotates counterclockwise accordingly, causing the cams 11 and 11' to rotate counterclockwise, and presses the butterfly plate sealing ring 18 to the valve seat sealing ring 10 in parallel until the butterfly plate 16 presses the valve seat 10 of the valve body, and the sealing surface is completely sealed. The butterfly valve is closed.

The above examples should not be regarded as limiting the present invention, but any insubstantial improvement made based on the specific implementation of the present invention should be within the protection scope of the claims of the present invention.

What is not mentioned in the present invention is applicable to the prior art.

Claims (3)

1. a kind of dual drive is without friction hard-sealing butterfly valve, the butterfly valve includes valve body, valve rod, butterfly plate and its drive device, described Drive device include handwheel and handle two parts, it is characterised in that be provided with outside the valve rod circular ring upper valve rod set and The central axis of lower valve rod set, handle and valve rod is overlapped, and is connected with valve rod interference, and handwheel bolt is connected with upper valve rod set, Torque is transmitted to upper and lower valve stem sleeve；Described upper and lower valve stem sleeve is fixed with upper bush and lower sleeve, overhead cam with flat key respectively With lower cam；It is connected in the middle part of valve rod by flat key with connecting rod, valve rod welds together with butterfly plate；The outer circumference surface of the valve rod Upper and flat key becomes in the circumference and a periphery face is provided with 180 degree angle, on the inner peripheral surface of connecting rod, is provided with straight with periphery face Footpath identical inner circumferential face, after assembling, the periphery face on valve rod is corresponding with the inner peripheral surface hole site on connecting rod, inner circumferential face It is interior to be provided with spring；The original state of the spring be incomplete compressive state, and spring-compressed state compression stress be less than fluid Jie The impulsive force of matter；The axial line of the valve rod exists with butterfly plate center to be deviateed, and is single eccentric structure.

2. dual drive according to claim 1 is without friction hard-sealing butterfly valve, its feature is in the upper bush and lower sleeve One end is plane, and connector is fastened on upper bush and lower sleeve with screw, and connector synchronously passes the motion of upper valve rod set Lower valve rod set is given, Upper shaft sleeve and Lower shaft sleeve, and Upper shaft sleeve and Lower shaft sleeve are separately installed between upper bush and lower sleeve and valve body The one end for being designed as agreeing with valve body is the structure of arc-shaped.

3. dual drive according to claim 1 is without friction hard-sealing butterfly valve, it is characterised in that the overhead cam and lower cam Some equal profile is plane, when butterfly valve is closed, and the face profile of overhead cam and lower cam compresses butterfly plate；When butterfly valve is opened, 90 degree of two plane rotating Vortexes of overhead cam and lower cam, unclamp the butterfly plate compressed.