JPS6357664B2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to an improvement in the seat structure of a valve body that can be used in various valves such as butterfly valves and plate valves. No matter where fluid pressure is applied, the sealing effect can be increased using the fluid pressure, and the present invention provides a seat structure capable of high-pressure sealing.

FIG. 1 is an enlarged cross-sectional view of a main part showing an embodiment in which the seat structure according to the present invention is applied to a butterfly valve. 1 is a seat ring made of an elastic material such as a fluorine-containing polymer, and the cross section is approximately L. A mounting leg 4 that is shaped like a letter and has flexibility by sandwiching a substantially arc-shaped groove 3 on the back side of the valve body pressure contact surface 2, and a sliding portion that protrudes substantially parallel to the mounting leg. 5, and is molded into an annular shape as a whole. The seat ring 1 is held in place between the body 6 and a fixed member at the mounting leg portion 4, and in this example, a split ring 7 and a settling ring 8 are used as the fixed members. That is, as shown in the figure, the mounting leg portion 4 is clamped between the split ring 7 and the body 6, and the split ring 7 and the split ring 7 are fixed by screws to the body 6. It is held between the body 6 and the common body 6.
9 is a gasket that prevents leakage to the outside in the radial direction. A mounting recess 10 is provided between the fixing member, that is, the split ring 7 and the settling ring 8, and the body 6, and defines the amount of deflection of the mounting leg portion 4 and the amount of movement of the sliding portion 5 when fluid pressure is applied. ing. In other words, the amount of deflection of the mounting leg portion 4 is
a and the end edge 7a of the split ring 7, and the amount of movement of the sliding portion 5 is restricted by the protruding edge 8a of the settling ring 8. Note that the projecting edge 8a has a plurality of notches at arbitrary positions on its circumference, and communicates with the mounting recess 10. The end surface 5a of the sliding portion 5 is formed as a slope in the direction in which the wall thickness of the sliding portion decreases toward the mounting leg 4, and the end surface of the sliding portion 5 is crimped to the crimping surface 7b of the split ring 7. A corresponding slope is also formed.

Figures 2 and 3 are schematic diagrams explaining the sealing action, and when fluid pressure is applied from the primary side, the
As shown in the figure, the valve body 11 moves toward the secondary side by the dimensional tolerance between the stem insertion hole and the stem, that is, _m1 , and the seat ring 1 also acts through the notch formed in the flange 8a. The sliding portion 5 is moved by m ₂ on the pressure bonding surface 7b by the fluid pressure, and the mounting leg portion 4 also bends as shown. It goes without saying that the substantially arc-shaped groove 3 greatly contributes to the movement of the sliding portion 5. In this case, the end surface of the sliding portion 5 is formed into an inclined surface in a direction in which the thickness of the sliding portion decreases toward the mounting leg portion 4, and the crimp surface 7b of the split ring 7 is also formed into an inclined surface corresponding to this. Because of this, it acts as a force that strongly presses the valve body pressure contact surface 2 against the sealing surface of the valve body 11, and a strong tight sealing state is obtained. When the sealing surface of the valve body 11 is sloped as shown in the figure, and the valve body pressure contact surface 2 is also a corresponding slope, the moving action of the seat ring 1 is caused by the sealing surface of the valve body 11 and the pressure contact surface 7b.
A wedge effect appears between the two and a stronger sealing effect can be achieved. Mounting leg 4
The position of the edge portion 6a of the body 6 that regulates the amount of deflection of the valve body 6 is such that a pressing state or wedge action of the valve body pressure contact surface 2 against the valve body 11 can occur, thereby preventing permanent distortion from occurring in the mounting leg portion 4. Position where possible.

FIG. 3 shows a case where fluid pressure is applied from the secondary side, and the valve body 11 similarly moves to the primary side by the dimensional tolerance between the stem insertion hole and the stem, that is, m ₁ , and the seat ring 1 The mounting leg 4 of
Deflects by m ₃ . In this case, since the sliding portion 5 is prevented from moving by the protruding edge 8a, if the amount of deflection of the mounting leg portion 4 is appropriately set by the end edge portion 7a of the split ring 7, A strong crimp sealing effect corresponding to the amount of movement of the valve body 11 is created between the valve body pressure contact surface 2 and the valve body 1.
This can be expected between the sealing surface of No.1 and the sealing surface of No.1. m ₄ is the interference generated on the circumference as the valve body 11 moves.

FIG. 4 shows the overall structure of a butterfly valve employing the seat structure as described above, and the same structural parts as above are designated by the same reference numerals. In other symbols, 17 is a stem, 18 is a bearing, 19 is a gland, and 20 is a gland packing.

In the above example, the split ring 7 is interposed between the settling ring 8 and the body 6, but a portion corresponding to the split ring may be formed integrally with the settling ring 8.

FIG. 5 is an enlarged cross-sectional view of a main part showing an embodiment in which the seat structure according to the present invention is adopted in a plate valve. In the case of the butterfly valve, the valve body pressure contact surface 2 is parallel to the flow path. However, in the case of a plate valve, it is formed in an annular shape such that the valve body pressure contact surface 2 is located on a plane perpendicular to the flow path, as shown in the figure. The cross-sectional shape is also substantially L-shaped, and on the back side of the valve body pressure contact surface 2, there is a mounting leg portion 4 having flexibility by sandwiching a substantially arc-shaped groove 3;
This also applies to the point that it has a sliding portion 5 that protrudes substantially parallel to the mounting leg portion 4 . 12 is a body, 13 is a set ring screwed to the body 12, and the seat ring 1 is attached with the mounting leg 4 held between the set ring 13 and the body 12. The end face of the sliding portion 5 is formed as a slope in a direction in which the thickness of the sliding portion decreases toward the mounting leg 4, and the crimp surface 13a of the settling ring 13 is also formed as a corresponding slope. Reference numeral 13b is a ridge for regulating the amount of movement of the sliding portion 5, and 13c and 12a are edge portions of each settling ring 13 and body 12, which regulate the amount of deflection of the mounting leg portion 4. That is, the mounting recess of the seat ring 1 is defined by the projecting edge 13b and the end edges 13c, 12a. Notches 12b communicate the secondary flow path with the insertion groove of the valve body 14, and are provided at multiple locations on the circumference. A support ring 15 is screwed onto the inner surface of the secondary body, and a pressure ring 16 made of a fluorine-containing polymer is fixed to the pressure contact surface of the valve body 14.

When fluid pressure is applied from the primary side, the fluid pressure as shown by the arrow in Figure A acts on the seat ring 1 as well, so the mounting leg 4 is not bent as in the case of the butterfly valve. While the sliding part 5 moves on the inclined pressure contact surface 13a, a force is generated that presses the valve body pressure contact surface 2 against the sealing surface of the valve body 14.
Good sealing condition can be obtained.

Furthermore, when fluid pressure is applied from the secondary side, the valve body 14 itself is strongly pressed against the seat ring 1 as shown by the arrow in Figure B, and the fluid in the direction of pressure contact with the valve body 14 is also applied to the seat ring 1 itself. Since pressure is applied, an extremely good sealing condition can be expected due to the combination of the two.

FIG. 6 is an illustrative diagram of the overall structure of a plate valve employing the seat structure as described above, and the same structural parts as above are indicated by the same reference numerals. In other symbols, 21 is a ground, and 22 is a ground packing.

As is clear from the above explanation based on the examples,
The seat structure of the valve body according to the present invention includes, on the back surface of the pressure contact surface of the valve body, a mounting leg portion which is made flexible by sandwiching a substantially arc-shaped groove, and which protrudes substantially parallel to the mounting leg portion. A generally annular elastic seat ring having a sliding portion is installed between the body and the mounting member while appropriately regulating the amount of deflection of the mounting leg portion and the amount of movement of the sliding portion, and the sliding portion and the sliding portion are mounted between the body and the mounting member. Since the crimping surface of the fixed member that the friction portion crimps against is sloped, even if fluid pressure is applied from either the primary side or the secondary side, the force that presses the valve body pressure contact surface against the sealing surface of the valve body is maintained as described above. works, and an extremely good sealing effect can be expected.

[Brief explanation of the drawing]

Fig. 1 is an enlarged sectional view of essential parts showing an embodiment of the seat structure according to the present invention applied to a butterfly valve, and Fig. 2 shows an operating state when fluid pressure is applied from the primary side. 3 is a schematic diagram showing the operating state when fluid pressure is applied from the secondary side, FIG. 4 is a sectional view illustrating the overall structure of a butterfly valve using the above seat structure, and FIG. The figure shows an example in which the seat structure of the present invention is applied to a plate valve. A shows the operating state when fluid pressure is applied from the primary side, and B shows the operating state when the fluid pressure This shows the operating state when FIG. 6 is a sectional view illustrating the overall structure of a plate valve employing the above-mentioned seat structure. 1... Seat ring, 2... Valve body pressure contact surface, 3...
...Groove, 4...Mounting leg part, 5...Sliding part, 6, 12
...Body, 10...Mounting recess.

Claims (1)

[Claims] 1. On the back surface of the valve body pressure contact surface, it has a flexible mounting leg and a sliding part that protrudes substantially parallel to the mounting leg, sandwiching a substantially arc-shaped groove, and has an annular shape as a whole. An elastic seat ring is provided, and the amount of deflection of the mounting leg and the amount of movement of the sliding portion due to fluid pressure are defined between the body and a fixing member that clamps and holds the mounting leg between the body and the body. A concave portion is provided, and the end surface of the sliding portion is formed as a slope in the direction in which the wall thickness of the sliding portion decreases toward the mounting leg, and a corresponding slope is formed on the surface of the fixing member to which the end surface of the sliding portion is crimped. Valve body seat structure.