JPH0743556Y2 - Gate valve seal structure - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a seal structure for a sluice valve provided in the middle of a flow path through which hydrocarbons generated by thermal decomposition pass through combustion exhaust gas, etc. On the other hand, in a sluice valve configured to open and close the flow passage in the valve box by sliding the slide valve body in a direction crossing the flow passage in the valve box, The present invention relates to a seal structure of a sluice valve in which a sealing valve box seat that is in sliding contact with a valve is attached to the valve box.

[Conventional technology]

In this type of sluice valve, conventionally, in order to prevent the fluid from leaking from the inside of the valve box while allowing the sliding valve body to slide,
A sealing valve box seat was used to press it strongly against the sliding valve body side.However, if the valve box seat is simply used, the coke will not stick to the sliding valve body surface during long-term use. There is a tendency for adhered substances such as the like to adhere, which hinders smooth sliding of the sliding valve body.

[Problems to be solved by the device]

To solve such a problem, for example, a metal scraper is provided in the valve box integrally with or separately from the valve box seat, and this is pressed against the sliding valve body side together with the valve box seat. Therefore, it is conceivable to scrape off the adhering substances with this metal scraper.

However, like the former, when the scraper is provided integrally with the valve box seat, the valve box seat is not a problem because it is originally made of carbon in consideration of the sealing function and the pressing pressure, Since the scraper is made of metal, if scraping off the deposit while receiving the same strong pressing force as the valve box seat, it will cause seizure with the surface of the sliding valve body. There's a problem. Therefore, in order to avoid seizure with such a structure, there is a problem in that the sealing property must be sacrificed to some extent, such as weakening the pressing force against the valve box seat.

Also, like the latter, if the metal scraper is configured separately from the valve box seat and is fixedly provided to the valve box separately from the valve box seat, a mounting structure dedicated to the scraper is required, which reduces the number of parts. Not only does it cause an increase, but the carbon valve box seat prevents the valve box from slipping out of the valve box and resists the pressure received from the sliding valve body that fluid pressure acts on when opening and closing the sliding valve body. Therefore, it is necessary to provide a retaining member and a reinforcing member so that the number of parts also increases. In addition, when the scraper itself is worn, the scraping function is extremely deteriorated, and there is a problem that the desired scraper action cannot be expected.

The object of the present invention is to make it possible to satisfactorily remove the deposits on the sliding valve body along with the sliding movement of the sliding valve body while maintaining good sealing performance, and also to simplify the structure. Another object of the present invention is to provide a sluice valve seal structure.

[Means for Solving the Problems]

The technical means of the present invention taken to achieve the above object are:
A sluice valve having a sliding valve body that is slidably operated in a direction traversing a flow path in the valve box, and having a sealing valve box seat that slides with respect to the sliding valve body is attached to the valve box. In the seal structure of (1), the valve box seat is attached to the valve box in a state where it is prevented from coming off by a metal seat ring, and the seat ring and the valve box seat are arranged in a perspective direction with respect to the sliding valve body. Each of them is movably attached to a valve box, and a first spring is provided to urge the seat ring in a direction of approaching the sliding valve body in a state where the seat ring is always in contact with the sliding valve body. The second spring is provided to bias the sliding valve body in a direction close to the sliding valve body via a ring.

[Action]

The effect of taking the above technical means is as follows.

That is, the seat ring is pressed against the sliding valve body by the first spring, which is different from the one for biasing the valve box seat, with the biasing force set to a desired value. While scraping off the material adhering to the surface of the sliding valve body as it slides, it moves in the direction close to the sliding valve body even if the seat ring wears due to sliding contact with the sliding valve body. Therefore, the pressure contact state with respect to the sliding valve body can always be maintained.

Further, while the valve box seat is prevented from bending by the backup ring, even if it wears, the valve box seat is always pressed against the sliding valve body by the second spring.

Since the metal seat ring prevents the valve box seat from coming off and also reinforces the valve box seat in cooperation with the backup ring due to its own rigidity, it is dedicated to the valve box seat. There is no need for retaining means or reinforcing means.

[Effect of device]

Therefore, the sliding contact surface of the sliding valve body can always be kept smooth by the scraping action of the seat ring, and the valve box seat and the sliding valve body can be brought into close contact with each other. Since the bending of the valve box seat due to the operation is pressed against the sliding valve body by the second spring while being prevented by the backup ring, the valve box seat can be reinforced while maintaining the seal against the sliding valve body. , It became possible to maintain good sealing performance of the gate valve for a long period of time.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 to 3, in a valve box (1), a sliding valve body (2) made of stellite metal is vertically movable between a raised valve opening position and a lowered valve closing position. ) Is provided, and the sliding valve body (2) is provided with an operating tool (4) which can be moved up and down through a valve rod (3) attached to the sliding valve body (2). The valve box seat (5) made of SC carbon that is in sliding contact with the valve box (1) is attached to the valve box (1) in a state where it is retained by the nickel cast iron seat ring (6), and the hydrocarbon gas generated by thermal decomposition or A sluice valve provided in a flow path for passing combustion exhaust gas is configured.

As shown in FIG. 2, the seat ring (6) and the valve box seat (5) are separately provided in the valve box (1) so as to be movable in the perspective direction with respect to the sliding valve body (2). ),
A first spring in the form of a disc spring that biases the sliding valve body (2) in the direction of approaching the sliding valve body (2) while always contacting the sliding valve body (2) regardless of the vertical movement of the sliding valve body (2). (7) is provided so that the seat ring (6) scrapes off the deposit such as coke that adheres to the surface of the sliding valve body (2) as it slides.

Further, the fluid in the flow path is present between the valve box (1) and the back surface of one of the valve box seats (5) and (5) sliding on both sides of the sliding valve body (2). The gland packing (8) is interleaved so that the coke does not collect when entering, and the valve box seat (5) is provided on the other rear side via the backup ring (9) with the valve box (1). Second spring (1) in the shape of a disc spring that urges the slider toward the sliding valve body (2).
0) is provided to improve the sealing property with respect to the sliding valve body (2).

The backup ring (9) also supports the first spring (7), and the seat ring (6) in addition to the valve box seat (5) is also supported by the second spring (10). It is pressed against the 2) side.

In the figure, (11) is a packing that closes each gap.

[Another embodiment]

The first spring (7) may have a reaction force received by the valve box (1).

The sliding valve body (2), the seat ring (6), and the valve box seat (5) may be made of various materials.

It should be noted that reference numerals are added to the claims of the utility model for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

The drawings show an embodiment of a sealing structure for a sluice valve according to the present invention. FIG. 1 is a cross-sectional view of the sluice valve, FIG. 2 is an enlarged cross-sectional view of an essential part, and FIG. 3 is a longitudinal cross-sectional view of the sluice valve. . (1) …… Valve box, (2) …… Sliding valve body, (5) …… Valve box seat, (6) …… Seat ring, (7) …… First spring, (9) …… Backup Ring, (10) …… Second spring.

Claims (1)

[Scope of utility model registration request] 1. A seal, comprising a sliding valve body (2) which is slidably operated in a direction traversing a flow path in a valve box (1), and slidingly contacting the sliding valve body (2). Is a seal structure of a sluice valve in which the valve box seat (5) of (1) is attached to the valve box (1), and the valve box seat (5) is a metal seat ring (6).
The seat ring (6) and the valve box seat (5) are attached to the valve box (1) in a state in which they are prevented from coming off, and can be moved separately in the perspective direction with respect to the sliding valve body (2). A first spring (which is attached to the valve box (1) and biases the seat ring (6) toward the sliding valve body (2) in a state where the seat ring (6) is in constant contact with the sliding valve body (2). 7) is provided, and a second spring (1) for urging the valve box seat (5) in a direction approaching the sliding valve body (2) via a backup ring (9).
Sealing structure for sluice valve with 0).