JP6377934B2 - Ball valve - Google Patents

Description

  The present invention relates to a ball valve.

The ball valve includes a valve box in which a liquid flow path is formed and a ball valve in which a through hole is formed to allow the liquid to pass through a wall of a sphere that dams the liquid, and opens or closes depending on the direction of the ball valve. It is supposed to be. And in order to ensure the watertightness between the valve box and the ball valve, a ball seat (valve seat) for seating the ball valve is arranged on each of the inlet side opening part and the outlet side opening part of the valve box. Yes. With such a configuration, the ball valve forms a space or gap in which liquid is sealed by the ball seat, the valve box, and the ball valve when the ball valve is fully opened or fully closed, and is sealed in the space or gap when cold. When the liquid is frozen, it expands and damages the valve box.
Conventionally, a ball valve that prevents damage due to freezing has been developed for this problem (for example, Patent Document 1 below).

  The ball valve described in Patent Document 1 is formed with a primary side inlet and a secondary side outlet, a valve body including a valve chamber, and a valve body that is rotatably disposed via a seat. A ball valve body that passes through a valve hole in a direction of a first axis connecting the secondary inlet and the secondary outlet and opens and closes between the primary inlet and the secondary outlet by rotation; and a ball valve And a communication passage that communicates the valve hole with the primary inlet of the valve body at the closed position of the body.

  Then, as shown in FIG. 4B of Patent Document 1, by providing a communication hole 98 that communicates with the primary inlet 80 at the closed position of the ball valve body 88, the fire hydrant valve 54 is closed in a closed state. Even when the water enters the valve hole 90 of the ball valve body 88 at the position, this water communicates with the water contained in the pipe connected to the primary inflow port 80 through the communication hole 98. It is in a state of being.

  For this reason, when the outside air temperature drops below the freezing temperature in winter and the water in the valve hole 90 of the ball valve body 88 and the surrounding valve box 74 is partitioned by the seals 84 and 86 and is frozen. The expanded portion of the frozen ice escapes to the communication hole 98 opened to the primary side, and even if the water in the valve hole 98 freezes and expands, the valve box 74 is not expanded and damaged. It has become.

JP 2013-22343 A

However, in the conventional ball valve body of the ball valve, since the valve hole 98 is opened on the outer spherical surface of the ball valve body 88, the opening edge is sharpened, and further, burr is generated at the opening edge. For this reason, there is a problem that the valve seat is damaged and the water tightness of the ball valve is lowered.
In view of the above problems, an object of the present invention is to provide a ball valve capable of preventing freezing that is difficult to reduce water tightness.

The ball valve of the present invention includes a valve box in which a flow path for flowing liquid is formed, a valve seat provided in the valve box, a ball valve seated on the valve seat and opening and closing the flow path, A valve shaft connected to the ball valve for rotating the ball valve, the ball valve having a drain hole for extracting the liquid that can stay between the valve box and the ball valve, and the ball An inlet side opening portion and a outlet side opening portion formed at positions facing each other in the axial direction of the flow path when the valve is in an open state, and the outer surface side of the opening wall portion forming the drain hole is The introduction side opening and the outlet side opening are chamfered and formed in a direction parallel to the flow path and perpendicular to the axial direction of the valve shaft, and the drain hole is It is formed in a direction orthogonal to the axial direction of the valve shaft, That.
According to this configuration, since the outer surface side of the opening wall portion that forms the drain hole is chamfered, it is possible to prevent damage to the valve seat on which the ball valve is seated by the corner of the opening wall portion when the ball valve rotates. Can do.
The ball valve of the present invention includes a valve box in which a flow path for flowing a liquid is formed, a valve seat provided in the valve box, and a ball valve that is seated on the valve seat and opens and closes the flow path. The ball valve is formed with a drain hole for extracting the liquid that can stay between the valve box and the ball valve, and the outer surface side of the opening wall part that forms the drain hole is formed on the ball valve. The valve seat is chamfered, and a ball seat for maintaining watertightness between the ball valve and the accommodating portion in which the ball valve is accommodated is provided in the valve seat, and the chamfered outer surface of the opening wall portion is provided. When the drain hole faces the upstream flow path , the position on the side is configured to be positioned upstream from the ball seat , and the drain hole faces the downstream flow path. It is configured to be positioned downstream of the ball seat when being And features.

  According to the present invention, it is possible to protect the valve seat on which the ball valve is seated and to prevent the water tightness of the ball valve from being lowered.

It is the sectional side view which showed the valve closing state of the ball valve which is one Embodiment of this invention. It is the top view which showed the handle | steering-wheel of the ball valve which is one Embodiment of this invention. It is the sectional side view which showed the valve opening state of the ball valve which is one Embodiment of this invention. It is sectional drawing which looked at the state which opened the ball valve which is one Embodiment of this invention in the XX line of FIG. 1 or FIG. It is sectional drawing which looked at the state which opened the ball valve which is one Embodiment of this invention halfway in the XX line of FIG. 1 or FIG. It is sectional drawing which looked at the state which closed the ball valve which is one Embodiment of this invention in the XX line of FIG. 1 or FIG.

Hereinafter, embodiments of the ball valve of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view of a ball valve 1 according to an embodiment of the present invention cut along a vertical plane including an axis L1 (only the handle is shown in a half sectional view).
As shown in FIG. 1, the ball valve 1 includes a valve box 2 in which a flow path F for flowing a liquid (for example, water) in one direction (arrow P direction) is formed, and a ball provided in the valve box 2. A seat (valve seat) 3 and a ball valve 4 that sits on the ball seat 3 and opens and closes the flow path F are provided. The ball valve 4 stays between the valve box 2 and the ball valve 4. A drain hole 5 for extracting the liquid to be obtained or a frozen substance of the liquid is formed, and the outer surface 4a side of the opening wall portion 20 (4W) forming the drain hole 5 is chamfered.

The valve box 2 includes a housing portion 6 in which a valve chamber R for housing the ball valve 4 is formed, and a ball that is formed in a cylindrical shape and introduces liquid toward the housing portion 6 and is disposed in the valve chamber R. An introduction part 7 (also referred to as a “ball presser”) that presses the valve 4 and a lead-out part 8 that is connected to the storage part 6 and leads out the liquid are provided.
The accommodating portion 6 is formed in a substantially cylindrical shape with the upstream half 6A having the axis L1 as a central axis, and the downstream half 6B having a common axis L1 and slightly spherical along the outer shape of the ball valve 4. Further, the downstream side is formed in a cylindrical shape that is connected to the lead-out portion 8 with the central axis as the axis L1.

A cylindrical mount 15 on which the valve shaft 9 is inserted and the handle 10 is placed is integrally formed in the housing portion 6.
The accommodating part 6 and the lead-out part 8 are integrally formed. One end 7a of the introduction part 7 is fitted in the housing part 6 in a watertight manner and fixed.

  The introduction part 7, the accommodating part 6, and the lead-out part 8 are a substantially cylindrical housing in which a flow path F penetrating in the direction of the axis L1 is formed as a whole. The mount 15 is formed in a cylindrical shape so as to protrude in the direction of the axis L2 orthogonal to the direction of the axis L1 in the housing portion 6, and the valve shaft 9 connected to the ball valve 4 is protruded from the opening 15a.

  The ball seat 3 is annularly arranged in the upstream opening R1 and the downstream opening R2 of the valve chamber R, and maintains the watertightness between the ball valve 4 and the accommodating portion 6, and the ball seat 3 The valve 4 is stably disposed in the valve chamber R.

  As shown in FIGS. 1 and 3, the ball valve 4 is formed in a hollow substantially spherical body having a substantially constant thickness. The wall portion 4W of the ball valve 4 is formed with a pair of introduction side opening portions 16 and outlet side opening portions 17 at positions facing each other in the direction of the axis L1. The inlet side opening 16 and the outlet side opening 17 are formed so as to have substantially the same opening area as the inlet 7 and the outlet 8, respectively, and the flow path F of the valve box 2 can be communicated in the direction of the axis L <b> 1. It can be done.

  As shown in FIG. 1 or 3, the drain hole 5 is a wall 4 </ b> W that faces the introduction portion 7 when the valve is closed, and connects the center of the introduction side opening 16 and the center of the discharge side opening 17. It is formed at the center viewed in the direction of the axis L4 perpendicular to the axis L3 (in this embodiment, a circle centered on the axis L4). The size of the drain hole 5 is preferably formed to a size that can withstand the water pressure when flowing through the flow path F at a water pressure of 0.5 MPa for 2 minutes.

The outer surface 4a side of the opening wall portion 20 of the ball valve 4 that forms the drain hole 5 is chamfered. The chamfered shape is a shape that cuts the opening wall portion 20 on a virtual plane S orthogonal to the axis L4 and avoids contact between the opening end portion of the drain hole 5 and the ball sheet 3. As long as the opening end of the drain hole 5 is in contact with 3 and is not damaged, the tip corner of the opening wall 20 may be, for example, smoothly curved.
The chamfered shape is a donut circle shape with the opening end portion of the drain hole 5 obtained by cutting the opening wall portion 20 on the virtual plane S as shown in FIG. As the plane S approaches the axis L2, the angle formed by the virtual plane S and the spherical surface of the ball valve 4 becomes an acute angle in the outer circumference circle of the chamfered portion, and the ball seat 3 is likely to be scratched. For this reason, it is preferable to form the chamfered outer circumferential circle in front of the ball sheet 3.

  With the above-described configuration, the introduction side opening 16 formed in the ball valve 4 and the introduction side opening 16 and the extraction side by rotating the ball valve 4 around the axis (rotation axis) L2 and the flow paths F of the introduction part 7 and the extraction part 8. The flow path F is opened by communicating with the opening 17, or the wall 4W of the ball valve 4 closes the flow path F and closes it.

The valve shaft 9 is inserted into the mount 15, and the valve shaft 9 protrudes from the opening 15 a formed in the mount 15 in the direction of the axis L 2.
As shown in FIG. 3, the valve shaft 9 is a rod-shaped member having one end 18 fitted to the ball valve 4 and the other end 19 fitted to the handle 10. One end portion 18 of the valve shaft 9 is formed in a polygonal shape in a sectional view such as a rectangle so as to be able to engage with the ball valve 4 and rotate.

The other end 19 of the valve shaft 9 is formed in a flat shape extending in the diameter direction of the opening 15 a of the mount 15. An intermediate portion 21 in the direction of the axis L2 of the valve shaft 9 is formed in a cylindrical shape, extends toward the ball valve 4 while being supported in the mount 15, and is rotatable about the axis L2.
A backup ring 24 is disposed between the O-rings 22 and 23 on the outer peripheral surface of the intermediate portion of the valve shaft 9, and a valve shaft presser 25 is interposed on the other end 19 side of the valve shaft 9.

As shown in FIGS. 2 and 3, the handle 10 has a cylindrical outer shape, and a knob portion that protrudes from the distal end surface so as to extend in the radial direction of the circle on the distal end surface (the upper end surface in this figure). 26 is provided. The handle 10 holds the valve shaft 9 inside and is attached to the mount 15 via a handle guide 27 provided on the mount 15 shown in FIG.
As described above, by rotating the handle 10, the valve shaft 9 can be rotated about the axis L2, and the ball valve 4 can be opened and closed.

Next, the usage method, operation, and function of the ball valve 1 will be described. 4 to 6 are cross-sectional views taken along the line XX of the operation until the ball valve 1 opened in FIG. 3 is closed.
As shown in FIGS. 1 and 3, the ball valve 1 is connected to a temporary pipe (not shown) or the like and opened or closed during pipe inspection or water pipe construction.

  The opening wall portion 20 of the ball valve 4 that forms the drain hole 5 is chamfered on the outer surface 4a side, and burrs generated along with the formation of the drain hole 5 are removed. It is possible to prevent the ball sheet 3 from being scratched and damaged at the tip of the opening wall portion 20 that forms the drain hole 5.

  When the ball valve 1 is opened, as shown in FIG. 4, the liquid flows in the direction of arrow P from the introduction portion 7 through the ball valve 4 toward the lead-out portion 8. When the handle 10 shown in FIG. 3 is rotated to close the ball valve 4 (half-opened), the ball valve 4 gradually flows along with its rotation as shown in FIG. While the path F is closed, the liquid in the ball valve 4 is poured into the ball valve 4 and the valve chamber R of the valve box 2.

  When the ball valve 1 is fully closed, the ball valve 4 substantially dams the liquid flowing into the introduction portion 7 as shown in FIG. 6 and dams the liquid in the valve chamber R. When the ball valve 1 is completely opened again as shown in FIG. 4, the ball valve 4 causes the liquid to flow into the flow path F, but accumulates in the gap 30 between the valve box 2 and the ball valve 4. The liquid is retained in the gap 30.

Therefore, when the ball valve 1 is placed in a fully open or fully closed state for a long time in the cold season, the gap 30 between the ball valve 4 and the valve box 2 shown in FIG. 4 or the ball valve 4 shown in FIG. In addition, the liquid accumulated in the valve chamber R surrounded by the valve box 2 may freeze.
In particular, when the ball valve 1 is temporarily used for opening and closing a pipe of a temporary pipe (not shown) in waterworks or the like, the ball valve 4 is fully closed or fully opened after the construction is completed. Alternatively, the ball valve 1 may be removed from the temporary pipe while the liquid remains in the gap 30.

  In such a case, since the ball valve 1 is not connected to a pipe (not shown), it is not possible to take a method in which a slight amount of water continues to flow through the flow path F to prevent freezing. Therefore, in particular, in the ball valve 1 that is detachable and temporarily used for temporary piping or the like, it is difficult to prevent the liquid staying in the valve chamber R from freezing in a cold environment.

However, according to the ball valve 1, since the drain hole 5 is formed in the wall 4 </ b> W of the ball valve 4, when the liquid freezes and the volume increases, the frozen liquid or the unfrozen liquid is drained. It is possible to escape from the hole to the flow path F.
The opening wall portion 20 of the ball valve 4 forming the drain hole 5 is chamfered at least at the tip on the outer surface 4a side as shown in FIGS. Even if it hardens outside the opening wall 20 of the hole 5, it can escape from the ball seat 3, preventing the ball valve 4 from rotating, or the frozen liquid from scratching and damaging the ball seat 3. Can be prevented.

  As a result, the ball valve 1 of the present invention prevents the ball seat 3 from being damaged at the tip of the opening wall portion 20 that forms the drain hole 5 due to the rotation of the ball valve 4, and ensures reliable water stop and running water. The effect that it can be maintained for a long time is obtained.

  Further, in the ball valve 1 according to the present invention, the outer surface 4a around the drain hole 5 escapes from the ball seat 3, so that the liquid accumulated in the valve chamber R is frozen and pushed out from the drain hole 5. Even if it freezes in the vicinity of the drain hole 5, it is possible to prevent the ball valve 4 from being prevented from rotating or to damage the ball seat 3 and to maintain an appropriate use.

In the above embodiment, the drain hole 5 is formed at the center when the ball valve is viewed in the direction of the axis L4. However, the present invention is not limited to this. What is necessary is just to be formed in the position which can connect the path | route F.
Moreover, although the inside of the ball valve 4 has a substantially spherical shape, the inside of the ball valve 4 may be formed so that the flow path F has a cylindrical communication shape.

1 Ball valve 2 Valve box 3 Ball seat (valve seat)
4 Ball valve 20 Opening wall 4a Outer surface 5 Drain hole F Channel S Virtual plane L1 Axis L3 Axis

Claims (2)

A valve box having a flow path for flowing liquid; a valve seat provided in the valve box; a ball valve seated on the valve seat to open and close the flow path; and connected to the ball valve; A valve shaft for rotating the ball valve,
The ball valve is formed at a position opposite to each other in the axial direction of the flow path when the ball valve is open, and a drain hole for extracting the liquid that can stay between the valve box and the ball valve. An inlet side opening portion and a outlet side opening portion,
The outer surface side of the opening wall that forms this drain hole is chamfered,
The introduction side opening and the outlet side opening are formed in a direction parallel to the flow path and orthogonal to the axial direction of the valve shaft,
The water drain hole is formed in a direction perpendicular to the axial direction of the valve shaft. A valve box in which a flow path for flowing liquid is formed; a valve seat provided in the valve box; and a ball valve that sits on the valve seat and opens and closes the flow path.
In the ball valve, a drain hole for extracting the liquid that can stay between the valve box and the ball valve is formed, and the outer surface side of the opening wall portion forming the drain hole is chamfered,
The valve seat is provided with a ball seat that maintains water tightness between the ball valve and a storage portion in which the ball valve is stored,
The position of the chamfered outer surface side of the opening wall is configured to be positioned upstream of the ball seat when the drain hole faces the upstream flow path, and the drain A ball valve configured to be positioned on the downstream side of the ball seat when the hole faces the downstream flow path .

Images