JPH1151204A - Valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To release fluid accumulated in a clearance part inside a plug guide hole by forming a fluid by-pass groove, which connects the clearance part inside the plug guide hole to a secondary side flow passage along the axial direction of a guide shaft, between the plug guide hole and the guide shaft. SOLUTION: In a flow rate controlling double seat valve, when both of upper and lower plugs 9, 10 are lifted so as to open a valve, fluid flowing into a primary side flow passage 6 is divided into upward fluid directed to an upper side passage 7a and a downward fluid directed to a lower side flow passage 7b of a secondary side flow passage 7, and then, the divided flows are converged together in a flow outlet 3 so as to be discharged. In this case, a plurality of fluid by-pass grooves 20 are formed between the inner circumferential face of a plug guide hole 16 in the lower plug 10 of a plug 8 and the outer circumferential face of a guide shaft 17, so that a clearance part 16a of the plug guide hole 16 is connected to the secondary side flow passage 7b. In this way, fluid accumulated in the clearance part 16a of the plug guide hole 16 can be easily discharged to the secondary side flow passage 7 through the by-pass grooves 20 when the plug 8 is lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve device mainly configured as a double-seat valve for controlling a flow rate.

[0002]

2. Description of the Related Art FIG. 11 is a longitudinal sectional front view showing a conventional double-seat type valve device, and FIG. 12 is an enlarged front view showing a plug in FIG. 11 in relation to a guide shaft. In the drawing, reference numeral 1 denotes a valve casing, which is composed of a valve body 1A and an upper lid 1B.
The valve body 1A has an inlet 2 and an outlet 3 for a fluid.

[0003] Reference numeral 4 denotes a partition provided in the valve body 1A. The partition 4 is provided with a seat ring 5.
Here, the partition wall 4 is a channel connecting the inflow port 2 and the outflow port 3.
A partition is formed between the secondary flow path 6 and the secondary flow path 7, and
The secondary flow path 7 is branched into an upper flow path 7a and a lower flow path 7b, and the upper flow path 7a and the lower flow path 7b join at the outlet 3.

[0004] Reference numeral 8 denotes a plug disposed in the valve casing 1. The plug 8 includes an upper plug 9 for controlling the opening and closing of an upper passage 7a, a lower plug 10 for controlling the opening and closing of a lower passage 7b, It has a double-seat plug structure composed of an inter-plug connecting shaft portion 11 that integrally connects the upper plug 9 and the lower plug 10 coaxially over the shaft portions of both.

[0005] Reference numeral 12 denotes a valve stem portion integrally protruded from the upper surface axis portion of the upper plug 9, and 13 denotes a valve stem guide hole provided in an upper lid 1B serving as a head portion of the valve casing 1. The valve stem 12 is fitted into the hole 13 so as to be able to move up and down. Reference numeral 14 denotes a stem guide hole provided in the upper lid 1B and communicates with the valve shaft guide hole 13. Reference numeral 15 denotes a stem guide hole 14
The plug stem connected to the plug stem 1
Reference numeral 5 is connected to an operating device (not shown) serving as a driving unit.

Reference numeral 16 denotes a plug guide hole provided in the lower plug 10 and having a lower end opened. Reference numeral 17 denotes a lower guide shaft which is attached to a lower lid 1C serving as a bottom side of the valve casing 1 and rises in the valve body 1A. The guide shaft 17 is fitted in the plug guide hole 16 to guide the lower plug 10 in the elevating direction.

Reference numeral 16a denotes a gap formed between the tip (the upper end in the figure) of the guide shaft 17 in the plug guide hole 16, and reference numeral 18 denotes a fluid escape hole (bypass hole) provided in the lower plug 10. The fluid escape hole 18 is formed on the characteristic surface (fluid flow surface) of the gap 16a and the lower plug 10.
The lower plug 10 is formed obliquely so as to allow the fluid accumulated in the gap 16a to escape to the lower flow path 7b when the lower plug 10 descends.

In the above, the upper plug 9, the lower plug 10 and the inter-plug connecting shaft 11, the plug guide hole 16 and the guide shaft 17, the valve shaft 12 and the valve shaft guide hole 13 of the upper plug 9, and the stem guide hole 14. And the plug stem 15
Each is formed in a perfect circular cross section. Therefore, the upper and lower plugs 9 and 10 have a support structure that can rotate integrally.

Next, the operation will be described. Upper plug 9
At the upper end opening of the seat ring 5 and the lower plug 10
When the upper and lower plugs 9, 10 are lifted and opened via the plug stem 15 by the operating device in the valve-closed state in which the abutments respectively contact the lower end openings of the seat ring 5, the primary side from the inflow port 2 of the valve casing 1. The fluid that has flowed into the flow path 6 passes through the upper end opening of the seat ring 5 and the upper flow path 7a of the secondary flow path 7
And a downward fluid flowing through the lower end opening of the seat ring 5 toward the lower flow path 7b.
The fluid flowing through the upper flow path a and the fluid flowing through the lower flow path 7b merge at the outlet 3 and are discharged.

When the upper plug 9 and the lower plug 10 are integrally lifted and opened, a space 16a is formed in the plug guide hole 16, and fluid flows into and flows into the space 16a. When the lower plug 10 integral with the upper plug 9 descends, it is released to the lower flow path 7b of the secondary flow path 7 through the fluid release hole 18.

[0011]

Since the conventional double-seat type valve device is constructed as described above, the plug guide hole 16 is provided.
Of the lower plug 10 in order to release the fluid accumulated in the cavity 16a of the lower plug 10.
Must be formed obliquely. In this case, since the fluid escape hole 18 must be opened in the characteristic surface of the lower plug 10, machining is very difficult. The oblique fluid release hole 18 opened on the characteristic surface of the side plug 10 has a problem that it disturbs the flow of fluid around the lower plug 10. Further, since the fluid escape groove 18 is generally small in diameter, there is a problem in that the fluid escape groove 18 is clogged when a slurry fluid such as petroleum or a petroleum fluid flows and does not serve any purpose. Further, a small gap is set between the plug guide hole 16 and the guide shaft 17 to slide the plug 8 (lower plug 10) along the guide shaft 17; If foreign matter such as solid matter or slurry enters and sticks, the plug 8 does not move. In this case, there is a problem that the valve casing 1 must be disassembled, the plug 8 and the guide shaft 17 must be taken out to remove the foreign matter. there were. further,
Since the plug 8 has a rotatable support structure, when the plug 8 receives a force due to the turbulence of the fluid in the valve casing 1, a pressure difference occurs in the fluid flowing along both sides of the plug 8 in this case. Due to the pressure difference, a rotational force is generated in the plug 8, and the plug 8 starts rotating due to the rotational force, so that the valve stem 12 and the plug stem 15 are twisted. There is also a problem that the connection joint and the operation device system are damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and the characteristic surface serving as a fluid flow surface of a plug is not subjected to any opening processing, and accumulates in a gap in a plug guide hole. It is an object of the present invention to obtain a highly reliable valve device that can release a fluid that has escaped and that does not disturb the flow around the plug due to the released fluid. Further, according to the present invention, when foreign matter such as solid matter or slurry in a fluid enters between the sliding contact surfaces of the plug guide hole and the guide shaft and is fixed, the foreign matter can be easily removed without disassembling the valve casing. The aim is to obtain a valve device that can be removed. Another object of the present invention is to provide a valve device that can prevent rotation of a plug and prevent damage to a plug system and an operating system caused by the rotation.

[0013]

According to a first aspect of the present invention, there is provided a valve device having a flow path to be controlled for opening and closing, and forming the flow path into a primary flow path and a secondary flow path. A valve casing, a plug disposed in the valve casing to control the opening and closing of the flow path, a plug guide hole provided in the plug, and a plug guide hole protruding into the valve casing and having the plug guide hole. A guide shaft that is fitted and guides the plug in the axial direction, wherein a gap is formed between the plug guide hole and the tip of the guide shaft. A fluid escape groove is formed along the axial direction of the guide shaft to connect the gap in the plug guide hole to the secondary flow path.

In the valve device according to the second aspect of the present invention, the fluid escape groove is formed by making the inner peripheral surface of the plug guide hole and the outer peripheral surface of the guide shaft have different cross-sectional shapes.

In the valve device according to the third aspect of the present invention, the fluid escape groove includes at least one groove formed in the inner peripheral surface of the plug guide hole or the outer peripheral surface of the guide shaft along the axial direction. Things.

According to a fourth aspect of the present invention, the plug guide hole or the guide shaft engages with the fluid escape groove to allow the plug to open and close in the axial direction and prevent the plug from rotating. To provide an engaging convex portion.

According to a fifth aspect of the present invention, there is provided a valve device, wherein a plurality of fluid relief grooves are formed in the guide shaft along the axial direction, and one of the fluid relief grooves is engaged with one of the fluid relief grooves in the axial direction of the plug. An engagement projection for allowing the opening and closing movement of the plug and preventing the rotation of the plug is detachably attached to the plug guide hole from the outside of the plug.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a longitudinal sectional side view showing a double-seat type valve device according to Embodiment 1 of the present invention, FIG. 2 is an enlarged front view showing a plug in FIG. 1 in relation to a lower guide shaft, and FIG. FIG. 13 is a sectional view taken along the line A, in which the same or corresponding parts as in FIGS. 11 and 12 are denoted by the same reference numerals, and redundant description is omitted.
In the drawing, reference numeral 20 denotes a plurality of fluid escape grooves formed between the inner peripheral surface of the plug guide hole 16 and the outer peripheral surface of the guide shaft 17 in the lower plug 10 of the plug 8. As shown in FIG. 3, the fluid escape grooves 20 are composed of four concave grooves formed in the guide shaft 17 along the axial direction, and as shown in FIGS. 16a and secondary side flow path 7b
And are connected.

Reference numeral 21 denotes an engagement protrusion provided on the lower plug 10 and protruding into the plug guide hole 16. The engagement protrusion 21 is used to connect one of the four fluid escape grooves 20. The plug 8 is engaged with the fluid release groove 20 by utilizing the plug 8, and in this engaged state, the plug 8 is allowed to open and close in the axial direction (up and down movement in the drawing) and to prevent rotation of the plug 8. Has become. In the first embodiment, the engaging projection 21 is formed of a bolt detachably attached to the lower part of the plug 8 from the outside.

Next, the operation will be described. The flow of the fluid when the plug 8 is lifted and opened is the same as the conventional one, and even if the plug 8 receives the force due to the turbulence of the fluid, the plug 8
Does not rotate due to the engagement between the fluid escape groove 20 and the engagement projection 21, so that the rotation of the plug 8 does not cause twisting of the valve stem 12 and the plug stem 15 and the like.
The connection joint between the valve stem 12 and the plug stem 15 and the operating system are not damaged.

Next, when the plug 8 is lowered, the fluid accumulated in the gap 16 a of the plug guide hole 16 is
By escaping to the secondary side flow path 7b through the fluid escape groove 20 in the axial direction of 7, the escaping fluid does not disturb the flow of the fluid around the lower plug 10.

A plurality of guide shafts 17 (four in the drawing)
(1), even if one of the fluid escape grooves 20 is clogged by a foreign matter such as solid matter or slurry in the fluid, the other fluid escape groove 20 is retained and a bypass for fluid escape is provided. It can function as a hole.

Further, when the fluid escape groove 20 with which the engaging projection 21 is engaged is damaged by the engagement with the engaging projection 21, the entire valve casing 1 is not disassembled without disassembling.
This can be dealt with by temporarily removing the guide shaft 17 together with the lower lid 1C and engaging the other fluid escape groove 20 with the engagement projection 21.

When the fluid slurry or the like adheres to the inner peripheral surface of the plug guide hole 16, the plug 8 is rotated by releasing the engagement of the fluid escape groove 20 by the engaging projection 21. Since the corner of the open end of each fluid relief groove 20 functions as a scraper, it is possible to remove the deposit such as the slurry.

Embodiment 2 FIG. 4 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 2 of the present invention.
In the first embodiment, a detachable bolt is used as the engaging projection 21. In the second embodiment, however, the engaging projection 21 is formed integrally with a part of the inner peripheral surface of the plug guide hole 16. It was done. Therefore, in the second embodiment, the same operation and effect as in the first embodiment can be obtained except that the corner of the open end of the fluid escape groove 20 functions as a scraper.

Embodiment 3 FIG. FIG. 5 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 3 of the present invention.
In the third embodiment, a single fluid relief groove 20 and an engagement protrusion 21 are formed in the outer peripheral surface of the guide shaft 17 along the axial direction, and the inside of the plug guide hole 16 of the lower plug 10 is formed. An engaging groove 22 is formed on the peripheral surface, and the engaging protrusion 21 is fitted into and engaged with the engaging groove 22. Therefore, according to the third embodiment, the pooled fluid in the gap 16a of the plug guide hole 16 shown in FIG. 1 can be released along the guide shaft 17 by one fluid release groove 20, and the engagement can be achieved. The rotation of the guide shaft 17 can be prevented by the engagement between the protrusion 21 and the engagement groove 22.

Embodiment 4 FIG. 6 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 4 of the present invention.
In the first embodiment, the four fluid relief grooves 20 are provided on the outer peripheral surface of the guide shaft 17 and the engagement protrusions 21 are provided on the lower plug 10 side. On the inner surface of the plug guide hole 16 of the lower plug 10, four fluid relief grooves 20 are provided, and on the part of the outer surface of the guide shaft 17, an engaging projection 21 is integrally provided to protrude. The mating projection 21 is fitted into and engaged with one of the four fluid escape grooves 20. Therefore, also in the fourth embodiment, the same operation and effect as in the first embodiment can be obtained except that the corner of the open end of the fluid escape groove 20 functions as a scraper.

Embodiment 5 FIG. 7 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 5 of the present invention.
In the fifth embodiment, the guide shaft 17 is formed in a cross-shaped cross section and the plug guide hole 1 of the lower plug 10 is formed.
By forming four engagement grooves 22 along the axial direction on the inner peripheral surface of 6, and fitting and engaging each side end of the cross-shaped portion of the guide shaft 17 into these engagement grooves 22, Four fluid escape grooves 20 are formed between the guide shaft 17 and the inner peripheral surface of the plug guide hole 16.

Therefore, the cross-sectional shapes of the circular inner peripheral surface of the plug guide hole 16 and the outer peripheral surface of the guide shaft 17 are different, and thus the plug guide hole 16 and the guide shaft 17 have different cross-sectional shapes. Also, the fluid escape groove 20 can be formed between them, and the above-described embodiment is performed except that the corner of the open end of the fluid escape groove 20 in the case of the first embodiment functions as a scraper. The same function and effect as those of the first embodiment can be obtained.

Embodiment 6 FIG. FIG. 8 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 6 of the present invention.
In the sixth embodiment, the guide shaft 17 is formed in a triangular cross section, and the inner circumferential surface of the
By forming the engagement grooves 22 and fitting and engaging the triangular corners of the guide shaft 17 in the engagement grooves 22,
Three fluid escape grooves 20 are formed between the outer peripheral surface of the guide shaft 17 and the inner peripheral surface of the plug guide hole 16.

Therefore, also in the case of the sixth embodiment, the circular inner peripheral surface of the plug guide hole 16 and the outer peripheral surface of the guide shaft 17 have different cross-sectional shapes. The plug guide hole 16
A plurality of fluid relief grooves 20 can be formed in the inside, and the same operation and effect as in the fifth embodiment can be obtained.

Embodiment 7 FIG. 9 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 7 of the present invention.
In the seventh embodiment, the guide shaft 17 is formed in an impeller shape in cross section (FIG. 9A), a cross shape in cross section (FIG. 9B), and a triangular cross section (FIG. 9C). At the same time, the plug guide hole 16 forms a round hole 23, as shown in FIG.
As shown in FIG. 10 (b) and FIG. 10 (c), the guide shaft 17 is fitted and engaged with the round hole 23.

Therefore, in the case of the seventh embodiment, the dirt adhering to the wall surface of the plug guide hole 16 can be removed by rotating the guide shaft 17 by the scraper function. An effect can be obtained.

[0034]

As described above, according to the first aspect of the present invention, the plug guide hole provided in the plug for controlling the opening and closing of the flow path in the valve casing, the plug guide hole protruding into the valve casing, A guide groove is provided between the guide shaft and the guide shaft, which is inserted into the plug guide hole and guides the plug in the axial direction. Since it was formed along the axial direction of the plug, the fluid relief groove can be easily formed without any processing on the characteristic surface which is the fluid flow surface of the plug,
Moreover, the fluid escape groove allows the fluid accumulated in the gap of the plug guide hole to escape to the secondary flow path along the guide shaft, so that the escaped fluid does not disturb the flow of the fluid around the plug. This has the effect of improving the reliability of the valve device.

According to the second aspect of the present invention, since the inner peripheral surface of the plug guide hole and the outer peripheral surface of the guide shaft have different cross-sectional shapes, a fluid escape groove is formed between them. The same effect as that of the first aspect can be obtained.

According to the third aspect of the present invention, at least one inner circumferential surface of the plug guide hole or the outer circumferential surface of the guide shaft is provided.
Since one fluid relief groove is formed, one fluid relief groove can be processed more easily than a plurality of fluid relief grooves.
In the case of a plurality of fluid relief grooves, even if one of the fluid relief grooves is clogged with foreign matter such as solid matter or slurry in the fluid, another fluid relief groove can cope with the problem. Furthermore, when a fluid escape groove is formed in the guide shaft, when slurry or the like adheres to the inner peripheral surface of the plug guide hole, the open end of the fluid escape groove functions as a scraper by rotating the plug. Therefore, there is an effect that the attached matter such as the slurry can be easily removed without disassembling the entire valve casing.

According to the fourth aspect of the present invention, the plug guide hole or the guide shaft is engaged with the fluid escape groove to permit the opening and closing movement of the plug in the axial direction and to prevent the rotation of the plug. Is provided, the plug can be opened and closed and moved without any trouble, but even if the plug receives the force due to the turbulence of the fluid in the valve casing, the plug will not rotate. Therefore, it is possible to prevent torsion of the valve stem and the plug stem due to the rotation,
There is an effect that the connection joint between the valve stem and the plug and the operating device system are not damaged by the torsion.

According to the fifth aspect of the present invention, a plurality of fluid relief grooves are formed in the guide shaft along the axial direction, and one of the fluid relief grooves is engaged with the guide shaft to open and close the plug in the axial direction. An engagement projection for allowing movement and preventing rotation of the plug is detachably attached to the plug guide hole from the outside of the plug, so that the fluid escape groove with which the engagement projection is engaged is formed. When the engagement projection is damaged by engagement with the engagement projection, the engagement projection is removed or loosened from the outside of the plug without disassembling the entire valve casing, and the engagement projection and the fluid escape groove are removed. After releasing the engagement once with the above, there is an effect that the engagement convex portion can be engaged with another undamaged fluid escape groove to cope with it.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view showing a double-seat valve device according to Embodiment 1 of the present invention.

FIG. 2 is an enlarged front view showing the plug in FIG. 1 in relation to a lower guide shaft.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a transverse sectional view showing a main part of a double-seat valve device according to Embodiment 2 of the present invention.

FIG. 5 is a transverse sectional view showing a main part of a double-seat valve device according to Embodiment 3 of the present invention.

FIG. 6 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 4 of the present invention.

FIG. 7 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 5 of the present invention.

FIG. 8 is a cross-sectional view showing a main part of a double-seat valve device according to Embodiment 6 of the present invention.

FIG. 9 is a transverse sectional view of a guide shaft according to a seventh embodiment of the present invention.

FIG. 10 is a cross-sectional view in which a guide shaft according to a seventh embodiment of the present invention is fitted and engaged in a plug guide hole.

FIG. 11 is a longitudinal sectional front view showing a conventional double-seat valve device.

FIG. 12 is an enlarged front view showing the plug in FIG. 9 in relation to a guide shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve casing 6 Primary flow path 7 Secondary flow path 8 Plug 16 Plug guide hole 16a Void part 17 Guide shaft 20 Fluid escape groove 21 Engagement convex part

Claims (5)

[Claims] 1. A flow path to be controlled for opening and closing, wherein the flow path is
A valve casing partitioning the secondary flow path and the secondary flow path, a plug disposed in the valve casing to control the opening and closing of the flow path, a plug guide hole provided in the plug, A guide shaft protruding into the valve casing and fitted into the plug guide hole to guide the plug in the axial direction, wherein a gap is formed between the plug guide hole and the tip of the guide shaft. In the valve device, a fluid escape groove is formed between the plug guide hole and the guide shaft to connect a space in the plug guide hole to a secondary flow path along the axial direction of the guide shaft. A valve device characterized by the above-mentioned. 2. The valve device according to claim 1, wherein the fluid escape groove is formed by making the inner peripheral surface of the plug guide hole and the outer peripheral surface of the guide shaft have different cross-sectional shapes. 3. The fluid escape groove according to claim 1, wherein the fluid escape groove comprises at least one groove formed along an axial direction on an inner peripheral surface of the plug guide hole or an outer peripheral surface of the guide shaft. Item 3. The valve device according to Item 2. 4. The plug guide hole or guide shaft has:
An engaging projection for engaging the fluid escape groove to allow the plug to open and close in the axial direction and for preventing rotation of the plug is provided. 3
The valve device according to claim 1. 5. The fluid escape groove includes a plurality of grooves formed in the guide shaft along the axial direction, and engages with one of the fluid escape grooves to allow the plug to open and close in the axial direction. 4. The valve device according to claim 1, wherein an engagement protrusion for preventing rotation of the plug is detachably attached to the plug guide hole from outside the plug. 5.