JPS6218788B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plate-type gate valve in which the state of contact between a valve seat and a valve element can be easily adjusted from the outside using an inclined sliding mechanism.

In the past, various types of gate valves have been developed and proposed, but the most common type is a wedge-shaped valve seat that is opposed to an annular valve seat that is closed by tightly fitting a side wedge-shaped weight type valve. This type of valve has many problems in terms of manufacturing and workability, making it difficult to completely close the valve, and the contact surface of the valve seat or valve element is easily damaged. Therefore, as a means to improve these defects, the valve was made into a plate shape,
A type of gate valve that opens and closes by moving it up and down, such as the gate valve shown in Japanese Patent Publication No. 18912-1971
Alternatively, there is a gate valve as disclosed in Japanese Patent Publication No. 46-14304. However, in the former type, the ring gasket, which forms the valve seat, is in constant contact with the valve plate and slides to open and close the valve pipeline, so it is natural that the ring gasket may become worn out. This is not desirable as it may lead to poor contact and leakage.
In addition, in the latter type, the valve seat is separated from the valve element to perform the opening/closing operation, which improves the sealing effect when the valve is closed, but the structure is complicated and it is inconvenient to handle.

Therefore, proposals have been made to make gate valves using this kind of plate valve more effective. For example, Japanese Patent Application No. 126921/1983
52520), a gate valve has a function of adjusting the contact state between the valve element and the valve seat by moving a valve seat piece equipped with a ring seal with respect to a plate-shaped valve element. Although this has been proposed, it not only increases the size of the valve body structure, but also complicates its adjustment mechanism, resulting in various practical problems.

The present invention provides a gate valve that has conventionally had many problems, particularly a gate valve equipped with a plate-type valve that is relatively simple and effective in structure, by improving the valve seat for the valve. The contact state of the valve body can be easily adjusted from one external location without complicating the structure and without disassembling the valve body, making it practically effective. Our goal is to provide gate valves.

The present invention provides a gate valve equipped with a plate valve in which a fluid passage hole and a flow-closing part are provided in a single valve plate, in which one inner surface of the part connected to the pipe part of the valve case is inclined to open downward. A valve seat gasket is interposed between the valve element formed on the surface and disposed in the central part of the valve case and the sloped surface of the valve case, and a seal gasket is interposed between the valve element and the sloped surface. A main valve seat piece is disposed which respectively abuts the inclined end faces corresponding to the main valve seat piece, and the inner end surface of the valve casing tube portion on the opposite side from the main valve seat piece is an annular seating surface parallel to the longitudinal axis of the valve casing. A sub-valve seat piece is disposed between the valve element and the valve holder, and the sub-valve seat piece is in contact with the valve holder and the inner ring seat surface of the valve casing with a seal packing interposed therebetween, and both of the main and auxiliary valve seat pieces are A pair of guide pieces protruding from the outer side are provided with slopes parallel to the slopes in the valve casing and serve as mutually sliding guide surfaces. The valve seats of both valve seat pieces are moved through the main valve seat piece by the displacement of the guide piece by moving the operation rod, whose tip is in contact with the lower surface of one valve seat and the other end is kept watertight and supported so as to protrude to the outside, to move back and forth. A cover is attached that is equipped with a valve seat adjustment mechanism configured to allow external adjustment of the contact state between the seal and the valve element.

The gate valve of the present invention will be explained below with reference to specific diagrams of one embodiment. In FIGS. 1 to 3,
Reference numeral 1 denotes the valve case main body, and 2 and 2' indicate valve case pipe parts, one of which protrudes somewhat long from the center of the valve case main body, and the inner end surface 3 of the pipe part 2 is an inclined surface that opens downward at an appropriate angle. The inner end of the other tube portion 2' is formed into a ring seat 3' that slightly protrudes from the inner wall of the main body 1 and is parallel to the center line of the main body. Reference numeral 4 designates a valve element in the form of a plate with an appropriate thickness, with an upper half serving as a flow-closing portion and a lower half having a passage hole 4' corresponding to the inner diameter of the tube. Reference numeral 5 denotes a main valve seat piece, one sliding surface 5' is made to be able to slide by conforming to the slope of the inner end surface 3 of the valve casing tube part, and the other surface is vertical and has an annular groove. A valve seat packing 7 is fitted into this annular groove. Reference numeral 6 denotes a sub-valve seat piece, which, unlike the main valve seat piece 5, has one sliding surface that loosely fits into the inner ring seat 3' of the valve case main body pipe portion 2'; The surface is vertical and the valve seat gasket 7 is fitted into an annular groove formed on the surface. Reference numerals 8 and 8 designate sealing O-rings or other gaskets on the joint surfaces between the outer surfaces of the main and sub-valve seat pieces and the valve case main body side. Reference numeral 9 denotes guide pieces protruding symmetrically from both outer sides of the main valve seat piece 5, and the guide surface 9' is formed as an inclined surface parallel to the sliding surface 5' of the main valve seat piece. , 10 are auxiliary guide pieces provided with inclined guide surfaces 10' that protrude symmetrically from both outer sides of the auxiliary valve seat piece 6 and come into contact with the guide surfaces 9' of the guide piece on one side of the main valve seat. .

Reference numeral 20 denotes a valve seat adjustment mechanism, and an opening 1 which doubles as a valve seat piece insertion part is wide open at the bottom of the valve case body 1.
1 is attached to the cover 12, and 21 is an operating rod whose tip abuts against the lower end of the main valve seat piece 5. The operating rod 21 has its base end placed outside the valve casing in a watertight manner through a stuffing box 22 provided on the cover 12. It stands out. 2
Reference numeral 3 denotes an adjustment plate, which is supported by stud bolts 24, 24 installed in the cover 12 at both sides of the operating rod 21, and whose upper surface center is connected to the operating rod 21.
The movement of the operating rod into and out is adjusted by the rotation of each nut 25 which abuts the end and is threaded onto the bolts 24, 24. Note that the cover 12 is provided with a receiving portion for the valve element 4 adjacent to the valve seat adjustment mechanism 20;
3 is the drain plug, 14 is the valve case body lid, 15 is
is a valve stem, and 16 is an opening/closing handle.

In the gate valve of the present invention thus constructed, when assembling the valve seat pieces 5, 6 and the valve element 4, the auxiliary valve seat piece 6 is first placed in a predetermined position through the opening 11 at the bottom of the valve case body 1. Then, after inserting the valve element 4 and connecting it to the lower end of the valve stem 15, the main valve seat piece 5 is inserted along the inclined inner end surface 3, and the valve seats of both valve seat pieces 5 and 6 are aligned with respect to the valve element 4. After that, the opening 11 is sealed with the cover 12 and the valve seat adjustment mechanism 20 is brought into contact with the gasket 7.
If the adjusting plate 23 is advanced by rotating the nut 25 screwed into the support bolt 24, when the operating rod 21 is pushed in by the adjusting plate 23, the main valve seat piece 5 will be moved at the tip of the operating rod 21. Then, the main valve seat piece 5 is pushed inward (towards the center of the valve case body) by the sliding surface 5' of the main valve seat piece 5 and the inclined inner end surface 3 of the valve case pipe portion, and the main valve The valve seat gasket 7 of the seat piece 5 comes into close contact with the valve element 4, and the guide pieces 9 on both outer sides of this main valve seat piece move upward at the same time, so that they come into contact with the guide surface 9' at an opposite slope. Since a minute gap is instantaneously created between the guide surface 10' of the sub guide piece 10 on the side of the sub valve seat piece 6, the valve element 4 immediately responds to the movement of the main valve seat piece 5 in the pipe axial direction. The valve seat gaskets 7, 7 attached to both valve seat pieces can be maintained in close contact with the valve element 4 as a result of the displacement to the seat piece 6 side without any force. Then, if the valve seat adjustment mechanism 20 is operated in the opposite manner to the above, the thrusting force against the main valve seat piece 5 by the operating rod 21 is reduced, so that the main valve seat piece 5
can be lowered to a position where it maintains contact with the tip of the operating rod 21, and then the auxiliary guide piece 10, which is slidably engaged with the guide piece 9 on one side of the main valve seat, is moved toward the center by sliding between the two sliding guide surfaces. It comes to be pushed back in the opposite direction, acting in a direction to loosen the contact state between the valve seat gaskets 7, 7 of both the main and sub-valve seat pieces and the valve element 4.

Therefore, the contact state of the valve seat gaskets 7, 7 with respect to the valve element 4 can be adjusted freely using the operation part of the valve seat adjustment mechanism 20 attached to the outside of the valve case body 1, as described above. The contact condition with the valve seat gasket can be easily set appropriately.

As described above, according to the gate valve of the present invention, the valve seat pieces are interposed on both sides of the valve valve separately from the valve casing, and one of the valve seat pieces is kept watertight, and the operating rod is operated from the outside. By operating the valve seat pieces through the valve body, the inclined guide surfaces inside the valve casing are slid together, and both the main and sub valve seat pieces are simultaneously interlocked, allowing the contact state of both valve seats to be adjusted and set appropriately. As a result, even if the valve remains installed in the piping, it is possible to quickly correct the contact condition and prevent leakage even when the valve is closed, and it is also possible to prevent repairs due to wear of the valve seat gasket. If necessary, the valve seat piece or valve element can be easily replaced or repaired without removing the valve from the piping, and the gate valve, which had many problems in the past, can be easily and effectively made. The practical effects are extremely great.

It goes without saying that the present invention is not limited to the above-mentioned embodiments in accordance with the spirit of the present invention, and that changes can be made within the technical scope of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an embodiment of the gate valve of the present invention, FIG. 2 is a cross-sectional view taken along the line XX in FIG. 1, and FIG. 3 is a cross-sectional view taken along the Y-Y line in FIG. 1... Valve case body, 2, 2'... Valve case pipe section, 3...
...slanted inner end surface, 3'...ring seat, 4...valve,
5... Main valve seat piece, 5'... Inclined sliding surface, 6...
... Sub-valve seat piece, 7... Valve seat packing, 8... Seal packing, 9... Main guide piece, 10... Sub-guide piece,
DESCRIPTION OF SYMBOLS 11... Opening, 12... Cover, 20... Valve seat adjustment mechanism, 21... Operation rod, 22... Stuffing box, 23... Adjustment plate, 24... Bolt,
25...Natsuto.

Claims (1)

[Claims] 1. In a gate valve equipped with a plate-shaped valve in which a passage hole and a flow-closing portion are provided on a single valve plate, one inner end surface of the valve casing tube portion is not an inclined surface that opens downward;
The inner end of the other pipe part has an annular seat surface parallel to the vertical axis of the valve case, and between the valve element and the inclined inner end surface, one surface is slidably fitted to the inclined inner end surface, and a valve seat is provided on the other surface. A main valve seat piece with a gasket fitted therein, and two parallel surfaces facing each other between the valve element and the ring seat surface, with a valve seat gasket fitted on the surface on the valve element side. Sub-valve seat pieces are each disposed with their respective valve seat packings in contact with the valve element, and the other surface of each valve seat piece in contact with the surface facing the valve casing with a seal packing interposed therebetween, and the main and sub-valve seat pieces A pair of guide pieces protruding from both outer sides of both valve seat pieces are provided with slopes facing each other and parallel to the inclined inner end face in the valve case, and serve as guide surfaces that slide together. The sliding guide is moved through the main valve seat piece by advancing and retracting an operating rod whose tip is in contact with the lower surface of the main valve seat piece and the other end is kept watertight and is supported to protrude outside. A gate valve comprising a valve seat adjustment mechanism configured to allow external adjustment of the contact state between the valve seat gasket of both valve seat pieces and the valve element by displacement of one part. .