JPH0350151B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is designed to prevent damage to the stem or disk when excessive operating torque is applied to gate valves and globe valves, and to destroy the yoke sleeve or yoke bushing, which can be replaced most easily. This is related to the valve that has been used.

Normally, a gate valve has a wedge-shaped disc 1 connected to a stem 2 which is non-rotatable but movable up and down, and a yoke sleeve 3 is screwed onto this stem 2, as shown in FIGS. 1 and 17. The sleeve 3 is rotatably attached to the yoke 4 but not vertically movable, and a handle wheel 5 is fixed to the yoke sleeve 3, and by rotating the handle wheel 5, the disc 1 is moved up and down to open and close. There is.

If this gate valve remains closed for a long time,
If the disc 1 and the body 6 lose their slipperiness, or if a force is applied to compress the valve from the piping side, or if the body 6 contracts due to a drop in temperature, the disc 1 may be strongly clamped to the body 6. When the valve is engulfed, the valve cannot be opened unless a large torque is applied to the handle wheel 5. In such a case, it is normal to remove the compressive force applied from the piping side and apply an impact to the valve body from the outside to loosen the tight contact between disc 1 and body 6 and open the valve. However, if such measures are not taken and excessive torque is applied to the handle wheel 5 and the stem 2 is forcibly pulled up, the K part or the stem, which is the hooked part of the disk 1, will be damaged as shown in FIG. 22
Depending on the design, the threaded portion of the stem 2 may stretch or break.

Conventionally, when excessive torque is applied to the steering wheel, the yoke sleeve, which is extremely easy to replace, is destroyed without damaging the system or disc as described above. . The conventional example will be explained based on FIGS. 5 to 7. First, in FIG. 5, a cut 8 is made in the collar 7 of the yoke sleeve 3, and an excessive torque is applied to the handle wheel 5. Then, regardless of whether the force applied to the yoke sleeve 3 is a force that pulls up the disc or stem or a force that pushes it down, the yoke sleeve 3 is sheared and fractured at section A in the figure. Also, in FIG. 6, the collar 7 of the yoke sleeve 3
The cut-out 9 is made from below, and in the case of Fig. 7, the collar 7 is made extremely thin. Even if the force is applied, the yoke sleeve will be sheared and fractured at part A.

However, as shown in FIG. 17, when the valve is closed, that is, when the stem is pushed down, the stem and disk are not damaged. Therefore, the structure shown in FIGS. 5 to 7 has the disadvantage that the yoke sleeve is damaged even when the valve is opened, except when necessary. Even if we prevent excessive torque from being applied to the steering wheel in order to prevent the threaded part of the stem from elongating or breaking when the valve is closed, the stem is usually made with sufficient strength and the above-mentioned opening If you compare it with the case of an abnormal situation, you can understand that it is only necessary to limit the torque to a larger value.

Next, a globe valve will be explained based on FIG. 2 and FIG.
The stem 12 is rotatably screwed into the stem 1.
A disc 15 for opening and closing a valve port 14 in the body 13 is connected to the lower end of the stem 12, and a handle wheel 16 is fixed to the upper end of the stem 12. In this globe valve, unlike the gate valve described above, the disc is not clamped to the body. Therefore, there is usually no need to take measures against excessive handle torque, such as with gate valves.

However, in extremely exceptional cases, if the disc 15 and the valve port 14 become stuck together due to rust, etc., if excessive torque is applied to the steering wheel 16 and the stem is forcibly pulled up, the first
The M portion, which is the hooking portion of the stem 12 shown in FIG. 8, is destroyed. In this case, it has been conventional practice to destroy the yoke bushing 11, which is extremely easy to replace without damaging the stem 12.This example will be explained with reference to FIGS. 8 to 10. In FIG. 8, a cut 18 is formed in the collar 17 of the yoke bush 11 from above, and in FIG. 9, a cut 19 is formed in the collar 17 from below.

FIG. 10 shows a case where the flange 17 is formed extremely thin, and in either case, if excessive torque is applied to the handle wheel 16 as in the case of the gate valve described above,
Regardless of whether the force applied to the yoke bushing 11 is a force that pulls up the disc or stem 12 or a force that pushes it down, the yoke bushing 11 will be sheared and fractured at section A in the figure.

However, when the valve is closed as shown in FIG. 18, the stem 12 and disc 15 are not damaged, but in the cases shown in FIGS. 8 to 10, the yoke bush 11 is It has the disadvantage of being damaged.

Therefore, when the valve is closed, it is sufficient to limit the torque to a larger value than when the valve is opened as described above.

The present invention overcomes the above-mentioned conventional drawbacks and prevents damage to other valve components by destroying the yoke sleeve or yoke bushing, which is the easiest to replace, when excessive operating torque is applied.
The purpose is to limit large torque when the valve is closed so that the yoke sleeve and yoke bushing are destroyed only when necessary.

Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 11 is a cross-sectional view showing the yoke sleeve portion of the gate valve according to the present invention.
is a yoke sleeve, this yoke sleeve 20
A flange 21 is formed at the lower end of the yoke sleeve 2.
0 is rotatably attached to the yoke 23 by holding the collar portion 21 with a sleeve presser 22, but not movable up and down. Further, the root portion 24 of the flange portion 21 is given a required radius of curvature R, and furthermore, a step 25 having a sharp corner is provided at the inner diameter portion of the flange portion 21 so as to cut into the flange portion 21. Reference numeral 26 denotes a stem, which is screwed into the yoke sleeve 20 so as to be movable up and down, and a handle wheel 27 is fixed to the upper part of the yoke sleeve 20.

In this embodiment, parts not shown in FIG. 11 will be explained using the reference numerals shown in FIG. When the valve is closed and the disc 1 is strongly restrained inside the body 6, if an attempt is made to open the valve by applying excessive torque to the handle wheel 27, the yoke sleeve 20 tries to pull up the stem 26. As a reaction force, the stem 26 attempts to pull down the yoke sleeve 20, causing shear failure at section B in FIG.

On the contrary, if an attempt is made to close the valve by applying excessive torque to the handle wheel 27, the yoke sleeve 20 will try to push down the stem 26, and as a reaction force, the stem 26 will push the yoke sleeve 20 down. It will try to pull it upwards. In this case, since the required radius of curvature R is given to the root portion 24 of the flange portion 21, the shearing area becomes large, and a failure that is a combination of shearing tension will occur at portion C in the same figure. This fracture requires a larger torque than the above-mentioned shear fracture of section B. Therefore, when the valve is closed, the yoke sleeve 20 is only affected when a much larger torque is applied than when the valve is opened. shear failure,
Prevent destruction of other valve parts.

FIG. 12 shows the yoke sleeve 2 of the above embodiment.
11 is a partial sectional view showing another example in which a step 28 is further added to the inner diameter part of 0, and the shear failure at part B in the same figure is the same as the example in FIG. The damage that occurs to the yoke sleeve 20 due to excessive torque in the valve direction is tensile damage at section D in the figure, and the valve closing torque is limited to a lower torque than the fracture at section C in Figure 11. This is what I did.

FIG. 13 shows that on the inner diameter part of the yoke sleeve 20,
This is a partial cross-sectional view in which an inner circumferential groove 29 is provided instead of a step.
This exhibits the same effect as the example shown in FIG. 11.

Next, FIG. 14 is a sectional view showing the yoke bushing portion of the globe valve according to the present invention. In the figure, 30 is a yoke bushing, and a flange 31 is formed at the lower end of the yoke bushing 30. is fixed to the yoke 33 by pressing it with a yoke bushing holder 32 so that it cannot move vertically or rotate. In addition, the base portion 34 of the collar portion 31 has
A required radius of curvature R is given, and a step 35 having a sharp corner is provided on the inner diameter portion of the flange portion 31 so as to cut into the flange portion 31.

Reference numeral 36 denotes a stem, which is screwed onto the yoke bush 30 so as to be movable up and down, and a handle wheel 37 is fixed to the upper end of the yoke bush 30.

In this embodiment, parts not shown in FIG. 14 will be explained using the reference numerals shown in FIG. When the valve is closed and the disc 15 is strongly restrained inside the body 13, if an attempt is made to open the valve by applying excessive torque to the handle wheel 37, the yoke bushing 30 tries to pull up the stem 36. As a result of this reaction force, the stem 36 attempts to pull the yoke bushing 30 downward, resulting in shear failure at section B in FIG. 14.

On the contrary, if an attempt is made to close the valve by applying excessive torque to the handle wheel 37, the yoke bush 30 will try to push down the stem 36, and as a reaction force, the stem 36 will push the yoke bush 30 upward. I will try to pull it up.

In this case, since the root portion 34 of the collar portion 31 is given the required radius of curvature R, the shearing area becomes large, and a failure that is a combination of shearing and tension occurs at the C portion in the figure. , this fracture requires a larger torque than the shear fracture at section B in the same figure, so when the valve is closed, the yoke bushing 30 will undergo shear fracture only when a much larger torque is applied than when the valve is open. and prevent damage to other valve parts.

FIG. 15 shows the yoke bushing 3 of the above embodiment.
14 is a partial cross-sectional view showing another example in which a step 38 is further added to the inner diameter portion of the valve. The breakage that occurs in the yoke bushing 30 due to excessive torque in the direction is a tensile breakage at section D, and the valve closing torque is limited to a lower torque than the breakage at section C in FIG.

FIG. 16 is a partial sectional view in which an inner circumferential groove 39 is provided in the inner diameter portion of the yoke bush 30 instead of a step, which exhibits the same effect as the example shown in FIG. 14.

Although the embodiments have been described above, the present invention has a handlebar fixed to a yoke sleeve which is screwed onto a stem connected to a disk and which is non-rotatable but movable up and down, and which is rotatable but fixed to a yoke so that it cannot be moved up and down. ,
A valve that opens and closes by moving the disc up and down by rotating the handle wheel, or a rotatable stem that is screwed into a yoke bushing that is fixed to the yoke so that it cannot move vertically or rotate, and is connected to the disc. In a valve that is opened and closed by fixing a handle wheel to the handle wheel and moving the disk up and down by rotating the handle wheel, a flange is provided on the outer diameter of the yoke sleeve or the yoke bush to prevent the yoke from moving up and down. The above-mentioned handle is mounted on the handle so that it cannot be moved vertically or rotated, and the base of the flange is provided with a required radius of curvature R, and a step or groove with a sharp corner is cut into the flange on the inner diameter. When the torque applied to the vehicle exceeds a limit, the excessive force applied to the yoke sleeve or yoke bushing by this limit torque will destroy the yoke sleeve or yoke bushing and prevent damage to other valve parts. Because of this structure, if excessive torque is applied to the steering wheel to open the valve that is stuck in the closed state, the yoke sleeve or yoke bushing will be destroyed, and the torque can be applied reliably without damaging other parts. Since the torque applied to the steering wheel in the opposite direction can be limited to a higher value than in the above case, the yoke sleeve or yoke bushing is is destroyed, and other valve parts can be reasonably protected.Furthermore, since the structure of the present invention is simple, processing of the yoke sleeve or yoke bushing is extremely easy and mass production can be performed at low cost. It has a positive effect.

[Brief explanation of drawings]

Figure 1 is a vertical sectional view of a conventional gate valve, Figure 2 is a vertical sectional view of a conventional globe valve, Figure 3 is an enlarged sectional view of the yoke sleeve portion of Figure 1, and Figure 4. 2 is an enlarged sectional view showing the yoke bushing part in FIG. 2, FIG. 5 is a sectional view showing a state in which the flange of the yoke sleeve for preventing excessive torque provided in a conventional gate valve has been sheared, and FIGS. The figure is a partial sectional view showing the state in which the flange of another example of a yoke sleeve installed in a conventional gate valve has been sheared, and Figure 8 shows the flange of a yoke bushing for preventing excessive torque installed in a conventional globe valve, which has been sheared. 9 and 10 are partial sectional views showing a state in which the flange portion of another example of a yoke bushing provided in a conventional globe valve has been sheared, and FIGS. 11 to 16 11 is an enlarged sectional view showing the yoke sleeve portion of the gate valve according to the present invention, and FIGS. 12 and 13 are diagrams showing the yoke sleeve portion of the gate valve according to the present invention. FIG. 14 is an enlarged sectional view showing another example of the provided flange portion, FIG. 14 is an enlarged sectional view showing the yoke bushing portion of the globe valve according to the present invention, and FIGS. 15 and 16 are partial sectional views showing other examples of the provided flange portion. FIG. 17 is a partial cross-sectional view showing other examples of the flange portion, FIG. 17 is a partial explanatory view illustrating a state in which the connecting portion between the stem and disk of a gate valve is destroyed, and FIG. 18 is a view showing the connection between the stem and disk of a globe valve. It is a partial explanatory diagram explaining the state where a part breaks down. 20... Yoke sleeve, 21... Flange, 23
... Yoke, 24 ... Base, 25 ... Step, 2
6...Stem, 27...Handle wheel, 28...Step, 29...Inner circumferential groove, 30...Yoke bushing,
31... Flange, 33... Yoke, 34... Root, 35... Step, 36... Stem, 37... Hand wheel, 38... Step, 39... Inner circumferential groove.

Claims (1)

[Claims] 1. By fixing a handle wheel to a yoke sleeve which is screwed onto a non-rotatable but vertically movable stem connected to a disc and which is rotatably but not vertically movable to a yoke, and by rotating this handle wheel. A valve that opens and closes by moving the disk up and down,
Or, the handle wheel is screwed onto a yoke bushing that is fixed to the yoke so that it cannot move vertically or rotate, and the handle wheel is fixed to a freely rotatable stem that is connected to a disk.
In this valve, which opens and closes by moving the disc up and down by rotating the handle wheel, a collar is provided on the outer diameter of the yoke sleeve or the yoke bush, so that the yoke cannot move up and down or cannot move up and down or rotate. Attach to the base of the flange, give the required radius of curvature R to the base of the flange, and provide a step or groove with a sharp corner on the inner diameter part by digging into the flange,
When the torque applied to the handlebar vehicle exceeds the limit, the excessive force applied to the yoke sleeve or yoke bushing due to the limited torque will destroy the yoke sleeve or yoke bushing, thereby preventing damage to other valve parts. A valve characterized in that it is configured to.