CN111927965A - A valve stem structure and butterfly valve without necking through shaft - Google Patents

Abstract

The invention discloses a valve stem structure without necking through shaft and a butterfly valve, comprising a valve stem body, a square tenon on the outer circumference of its lower connecting end, which are respectively a first tenon surface, a second tenon surface and a third tenon surface and the fourth tenon surface; taking the center of the valve stem body as the origin, the first tenon surface and the second tenon surface are symmetrically arranged with respect to the Y axis, and the angle between the first tenon surface and the second tenon surface and the X axis is 32.5 °; the angle between the plane passing through the edge and the origin of the first tenon surface and the Y axis is 10°; the angle between the plane passing through the lower edge and the origin of the first tenon surface and the X axis is 35°; the second tenon surface The third tenon surface and the third tenon surface are symmetrically arranged relative to the X axis; the third tenon surface and the fourth tenon surface are symmetrically arranged relative to the Y axis. The combination of the inclined square tenon structure and the lower bushing makes up for the serious technical defect of the traditional design of the through-shaft pinless valve stem necking, maximizes the use of the shaft material, and greatly improves the service life of the valve; it is more reasonable in structure and better in performance. Reliable, the valve stem is easy to repair and replace.

Description

A valve stem structure and butterfly valve without necking through shaft

technical field

The invention belongs to the technical field of valve manufacturing, and in particular relates to a valve stem structure and a butterfly valve without necking through shafts for valves.

Background technique

The design of the valve stem (valve stem), the main part of the universal butterfly valve, is the most important part of the valve design. The rod should be rigidly connected with the valve plate, and then the torque input by the transmission device on the upper part of the valve rod is converted into the switching force of the valve (valve plate) to drive the valve switch. The related designs are compared and analyzed as follows:

1 Traditional non-necked thru-shaft design:

In this design, the valve stem passes through the valve plate, the material of the shaft is not wasted, and sufficient design strength can be obtained, but the valve plate and the valve stem must be fixed by radially punching pins.

2 necked through shaft design:

In this design, the valve stem passes through the valve plate, but because the square tenon connection or spline connection is used with the valve plate, the phenomenon that the upper and lower shaft diameters of the valve stem are different, that is, necking, so that the valve plate and the valve can be fixed without hitting pins. Rod, good interchangeability, good installation process.

However, the valve stem of this design has a step design with inconsistent shaft diameters, especially the step appears at the connection between the valve plate and the valve body, resulting in stress concentration and easy fracture. At the same time, this design material wastes a lot and cannot obtain sufficient design strength.

In summary, there is no valve stem with through shaft and no necking in the market at present. The design of the present invention changes this situation. Through the design of the butterfly valve with no necking and sloping valve stem, the shaft material is maximized, and at the same time It cooperates with the square tenon of the shaft sleeve to realize the transmission of torque.

SUMMARY OF THE INVENTION

In view of the problems existing in the prior art, the present invention provides a valve stem structure and a butterfly valve without necking through shaft.

The present invention is realized in the following way: a valve stem structure without necking through shaft for a valve includes a valve stem body, characterized in that the outer circumference of the lower connecting end of the valve plate body is provided with a square tenon, wherein the square tenon consists of four The tenon surfaces are surrounded by tenon surfaces, which are the first tenon surface, the second tenon surface, the third tenon surface and the fourth tenon surface; with the center of the valve stem body as the origin, the four tenon surfaces are respectively distributed on the first tenon surface. In the quadrant, the second quadrant, the third quadrant and the fourth quadrant, the first tenon surface and the second tenon surface are arranged symmetrically with respect to the Y axis, and the included angle between the first tenon surface and the second tenon surface and the X axis is 32.5° ; The angle between the plane passing through the edge and the origin on the first tenon surface and the Y axis is 10°; The angle between the plane passing through the lower edge and the origin of the first tenon surface and the X axis is 35°; among them, the second tenon The surface and the third tenon surface are arranged symmetrically with respect to the X axis; the third tenon surface and the fourth tenon surface are arranged symmetrically with respect to the Y axis.

In the above technical solution, the length of the square tenon is 0.8-1.5 times of the shaft diameter.

In the above technical solution, the depth of the four tenon surfaces of the square tenon is 2% of the shaft diameter.

The invention also discloses a butterfly valve, comprising a valve body, a valve plate, a valve stem, and a lower shaft sleeve installed in the lower shaft seat and connected to the valve stem; it is characterized in that the valve stem adopts the above-mentioned valve stem, and the lower shaft sleeve The inner circumference of the valve stem is provided with a square tenon through groove matching the square tenon at the lower end of the valve stem; the square tenon at the lower end of the valve stem is inserted into the square tenon through groove of the lower bushing; the valve stem of the valve plate is installed The lower end in the hole is provided with a protruding square tenon through groove matching the square tenon at the lower end of the valve stem.

The advantages and technical effects of the present invention: the present invention adopts the above-mentioned technology and adopts the combination of the slanted tenon structure and the lower shaft sleeve to make up for the technical defect of the traditional design of the through shaft without pin valve stem necking, and the valve shaft without necking is necked. When the valve plate is closed, the maximum arc surface of the valve stem supports the pressure of the valve plate. When it is rotated to open a small angle, generally 25-30 degrees, the pressure level impact force of the valve plate is all It is greatly reduced and the service life of the valve is greatly improved; it does not require the necking design of the valve stem, especially the long valve stem, and maximizes the use of the shaft material, which is convenient for maintenance and replacement.

Description of drawings

Fig. 1 is the valve stem structure schematic diagram of the present invention;

Fig. 2 is A-A sectional view in Fig. 1;

Figure 3 is a schematic diagram of the valve body structure;

Fig. 4 is B-B sectional view in Fig. 3;

Figure 5 is a schematic diagram of the valve plate structure;

Fig. 6 is C-C sectional view among Fig. 5;

Figure 7 is a schematic diagram of the structure of the lower bushing;

Fig. 8 is a side view.

In the figure, 1, valve stem body; 1-1, square tenon; 1-11, first tenon surface; 1-12, second tenon surface; 1-13, third tenon surface; 1-14, fourth tenon face; 2. valve body; 3. valve plate; 3-1, square tenon slot; 4, lower bushing; 4-1, square tenon slot.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

Please refer to FIG. 1 to FIG. 8 , a valve stem structure without necking through shaft for a valve includes a valve stem body 1, and the outer circumference of the lower connecting end of the valve plate body is provided with a square tenon 1-1, wherein the square tenon is formed by Four tenon surfaces are enclosed, namely the first tenon surface 1-11, the second tenon surface 1-12, the third tenon surface 1-13 and the fourth tenon surface 1-14; the center of the valve stem body is The origin, where the four tenon surfaces are respectively distributed in the first quadrant, the second quadrant, the third quadrant and the fourth quadrant, wherein the first tenon surface and the second tenon surface are symmetrically arranged with respect to the Y axis, and the first tenon surface and The angle between the second tenon surface and the X axis is 32.5°; the angle between the plane passing through the edge and the origin of the first tenon surface and the Y axis is 10°; the plane passing through the lower edge and the origin of the first tenon surface and the X axis The included angle of the axes is 35°; wherein, the second tenon surface and the third tenon surface are arranged symmetrically with respect to the X axis; the third tenon surface and the fourth tenon surface are arranged symmetrically with respect to the Y axis.

In the above technical solution, the length of the square tenon is 0.8-1.5 times of the shaft diameter.

In the above technical solution, the depth of the four tenon surfaces of the square tenon is 2% of the shaft diameter, and the strength is high.

The present invention also discloses a butterfly valve, comprising a valve body 2, a valve plate 3, a valve stem 1 and a lower shaft sleeve 4 installed in the lower shaft seat and connected to the valve stem; the valve stem adopts the above-mentioned valve stem, and the lower shaft sleeve The inner circumference of the valve stem is provided with a square tenon through groove 4-1 that matches the square tenon at the lower end of the valve stem; the square tenon at the lower end of the valve stem is inserted into the square tenon through groove of the lower bushing; in the above technical solution, Preferably, the lower end of the valve stem mounting hole of the valve plate 3 is provided with a square tenon through groove 3-1 matching the square tenon at the lower end of the valve stem. The torsional rigid connection between the valve stem and the valve plate is formed, and the other part is connected with the lower bushing to ensure the integrity and rotation of the valve shaft.

When the valve plate is closed, the valve stem bears the total pressure formed by all the pressures on the valve plate. At the same time, the maximum outer circle of the valve shaft is used to support the force of the valve plate by using the characteristics of the valve that the valve bears the maximum pressure and torque when the valve is closed. , When the valve plate is fully open and the force is very small, the smallest arc surface is used to bear the pressure of the valve plate, the structure is more reasonable, the performance is more reliable, and the valve stem is easy to maintain and replace.

This structural design maximizes the strength of the material itself, and uses a 35-degree design angle to support the valve plate with a large arc surface. There is no design defect that the constricted valve shaft causes stress concentration at the constriction, and when the valve plate rotates to open a When the small angle is generally 25-30 degrees, the impact force of the pressure level on the valve plate is greatly reduced. At this time, although the valve shaft rotates to the aspect of less tangential force, it has enough strength. Losses do get a rigid torsional force requirement. At the same time, the design reserves a 10-degree arc surface when the valve is normally open to overcome the unstable vibration of the valve plate caused by the impact of the medium.

The present invention adopts the above-mentioned technology and adopts the combination of the inclined square tenon structure and the lower shaft sleeve to make up for the technical defect of the traditional design of the through-shaft pinless valve stem necking, and greatly improve the service life of the valve; it does not require the valve stem, especially the long valve. The rod is necked down to maximize the use of shaft stock for easy maintenance and replacement.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (4)

1. A valve stem structure without necking through shaft for a valve, comprising a valve stem body, characterized in that the outer circumference of the lower connecting end of the valve plate body is provided with a square tenon, wherein the square tenon is enclosed by four tenon surfaces They are the first tenon surface, the second tenon surface, the third tenon surface and the fourth tenon surface; taking the center of the valve stem body as the origin, the four tenon surfaces are distributed in the first quadrant and the second quadrant respectively. , in the third quadrant and the fourth quadrant, wherein the first tenon surface and the second tenon surface are symmetrically arranged with respect to the Y axis, and the angle between the first tenon surface and the second tenon surface and the X axis is 32.5°; The angle between the plane of the upper edge and the origin and the Y axis is 10°; the angle between the plane passing through the lower edge and the origin of the first tenon surface and the X axis is 35°; among them, the second tenon surface and the third tenon The surfaces are arranged symmetrically with respect to the X axis; the third tenon surface and the fourth tenon surface are arranged symmetrically with respect to the Y axis. 2 . The through-shaft valve stem structure without necking according to claim 1 , wherein the length of the square tenon is 0.8-1.5 times the shaft diameter. 3 . 3 . The through-shaft valve stem structure without necking according to claim 1 , wherein the depth of the four tenon surfaces of the square tenon is 2% of the shaft diameter. 4 . 4. A butterfly valve, comprising a valve body, a valve plate, a valve stem and a lower shaft sleeve installed in a lower shaft seat and connected to the valve stem; characterized in that the valve stem adopts the valve according to any one of the above claims 1 to 3 The inner circumference of the lower shaft sleeve is provided with a square tenon through groove matching the square tenon at the lower end of the valve stem; the square tenon at the lower end of the valve rod is inserted into the square tenon through groove of the lower shaft sleeve; The lower end of the valve stem mounting hole of the valve plate is provided with a square tenon through groove matching the square tenon at the lower end of the valve stem.

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