JPH08128563A - Piston type gate valve - Google Patents

Abstract

PURPOSE: To provide a piston type gate valve in which rigidity in the diameter direction of a valve element is lowered, damage and burning can be prevented, and excessive accumulation of dust inside a valve casing can be prevented. CONSTITUTION: Gas penetrating into the inside a valve casing 1 via a clearance between the valve casing 1 and a valve element 10 can be let flow outward to an outlet 3 via a separation part on the outside of the downstream side of a port 17, and a quantity of dust penetrating into the inside of the valve casing 1 can be reduced. When the gas penetrates the clearance and the dust is bitten by sliding faces, the valve element 10 is shrunk and reduces a clearance C of a slit 11 against elastic force of an elastically energizing tool 16. As rigidity in the diameter direction is low in the valve body 10, a clearance is automatically regulated, so that damage of the sliding face by dust, burning preventing open/close operation of the valve element 10, and excessive increase in push/pull operation force are prevented. The diameter of the valve element 10 is expanded/shrunk so as to prepare a condition for changing a clearance in the slit 11 by means of operation of a clearance regulating device 12, so that the clearance is optionally regulated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piston type gate valve which is arranged in a gas passage containing, for example, powder particles.

[0002]

2. Description of the Related Art Conventionally, as a piston type gate valve of this type, for example, a structure shown in FIG. 5 has been provided.
That is, in the tubular valve box 31, an inflow port 32 and an outflow port 33 are formed in the middle portion in the longitudinal direction thereof in the directions orthogonal to each other and face each other, and the inner circumferential surface has a tubular body. Liner 34
Is being constructed. In addition, a top cover is attached to the end of the valve box 31.
35 and a bottom cover 36 are attached.

A tubular valve element 37 is slidably disposed inside the valve box 31, that is, inside the body liner 34, and a passage valve seat portion 37A on the tip side of the valve element 37 is provided. Is
A cylindrical port 38, which can communicate between the ports 32 and 33, is fixed to both ends of the cylindrical port 38 on the inner surface of the valve body 37 in a dense manner. The valve body
A valve rod (such as a piston rod of a cylinder for opening / closing operation) 39 through which the top cover 35 is inserted is connected to the inner surface side of the shutoff valve seat portion 37B which is the base end side of 37.

According to this conventional structure, by pulling and moving the valve body 37 through the valve rod 39, as shown in FIG.
The ports 38 are communicated with each other through the port 38, so that the gas G can flow from the inflow port 32 through the port 38 to the outflow port 33.
In addition, by pushing and moving the valve element 37 via the valve rod 39, the shut-off valve seat portion 37B is opposed to both the openings 32, 33, and thus the both openings 32, 33.
You can block the gap. Then, for example, when the valve body 37 is opened and closed while the gas G containing dust (powder particles) is flowed, a part of the gas G containing dust is generated in the gap between the valve body 37 and the body liner 34. Enter the tip space 40 from
As a result, dust gradually accumulates in the tip space 40.
The dust collected in the tip space 40 can be discharged by removing the bottom cover 36.

[0005]

However, according to the above-mentioned conventional structure, when the valve body 37 is opened and closed, dust is trapped between the valve body 37 and the body liner 34, and the sliding surface catches the dust. It will be crowded. At this time, since the cylindrical valve body 37 has high radial rigidity, the sliding surface is scratched by dust, or the valve body 37 cannot be opened / closed due to burning, and further, the valve rod 39. The push-pull operation force of may become excessive. Further, the work of removing the bottom cover 36 and discharging the dust is regularly performed, and during that time, the dust remains in the tip space 40. Therefore, if the work of discharging the dust is neglected, excessive dust will be accumulated in the tip space 40, and it will not be possible to fully open or close it at the time of opening / closing operation. Therefore, it is necessary to frequently perform maintenance without neglect.

The object of the present invention is to reduce the rigidity of the valve body in the radial direction to prevent damage and burning, and to prevent excessive accumulation of dust in the valve box. The point is to provide a valve.

[0007]

In order to achieve the above object, a piston type gate valve of the present invention comprises a valve box having an inflow port and an outflow port, and a slidably disposed inside the valve box. A piston-type gate valve consisting of a valve body having a port that can communicate with both ports, wherein the downstream side portion of the port is separated from the valve body, and the axial direction is provided at least at one position in the circumferential direction of the valve body. The slit is provided, and the gap adjusting device having the elastic biasing member that widens the interval of the slit is provided.

[0008]

According to the above-described structure of the present invention, the valve body is pulled and moved so that the inflow port and the outflow port communicate with each other through the port (opening operation), so that the gas flows from the inflow port through the port. May flow to outlet. Further, the valve body is pushed and moved so that the shutoff valve seat portion faces (closes) the inflow port and the outflow port, so that the two ports can be shut off. Then, for example, when the valve body is opened and closed while the gas containing dust (granular particles) is flowing, the gas that has entered the valve box through the gap between the valve box and the valve box is downstream of the port. It will flow out to the outflow port through the separating portion formed on the outside of the side, so that the amount of dust accumulated in the valve box can be reduced.

As the dust-containing gas flows in this manner, the dust-containing gas enters the gap between the valve box and the valve body at the inlet and outlet of the port, and the sliding surface catches the dust. It will be crowded. At this time, the valve body
It becomes smaller so as to narrow the gap between the slits against the elastic force of the elastic biasing device. In this way, the valve body is in a state where the clearance is automatically adjusted due to its low radial rigidity, so that the sliding surface is scratched by dust, or seizure causes the valve body to be unable to open and close. Moreover, the push / pull operation force does not become excessive. Also, when used at a high temperature and the temperature drops, the valve body will be held in the valve box side, but at this time the slit will make the valve body smaller, so the push-pull operation force will not become excessive. .

The above-mentioned gap between the valve box and the valve body can be arbitrarily adjusted by expanding / contracting the valve body such that the gap between the slits is changed by operating the gap adjusting device. Since a large amount of dust does not easily accumulate in the valve box, the number of maintenance operations can be reduced.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the tubular valve box 1, an inflow port 2 and an outflow port 3 are formed in an intermediate portion in the lengthwise direction thereof so as to face each other in a direction orthogonal to the lengthwise direction. And valve box 1
A cylindrical body liner 4 is applied to the inner peripheral surface of the. A top cover 5 and a bottom cover 6 are detachably attached to the end of the valve box 1 via bolts 7 and 8, respectively. In addition, the bottom cover 6 in the valve box 1
A tip space 9 is formed on the side.

A tubular valve element 10 is slidably disposed inside the valve box 1, that is, inside the body liner 4. The valve body 10 is composed of a passage valve seat portion 10A on the tip end side (bottom cover 6 side) and a shutoff valve seat portion 10B on the base end side (top cover 5 side). At least one position in the circumferential direction of the valve body 10, that is, at two positions in the middle between the inflow port 2 and the outflow port 3, slits 11 are provided in the longitudinal direction (axial direction).
Is provided over the entire length of the valve body, and thus the valve body 10 is divided into two. A gap adjusting device 12 having elastic biasing members for expanding the space S between the slits 11 is provided at three positions (a total of six positions) in the lengthwise direction between the two divided bodies.

That is, the gap adjusting device 12 is arranged inside the slit 11, and is fixed to the valve body 10 side and is provided with a pair of elastic biasing device mounting seats 13 sandwiching the slit 11 part. And a pair of elastic biasing member receiving members 15 that are attached to these elastic biasing member mounting seats 13 via adjustment operation tools (bolts, nuts, etc.) 14 and face each other, and between both elastic biasing member receiving members 15. A compression spring (an example of an elastic urging tool) 16 and the like arranged in the.

The passage valve seat portion 10A is provided with a cylindrical port 17 which allows communication between the inflow port 2 and the outflow port 3.
An upstream side portion of the port 17 that can communicate with the inflow port 2 is formed in the straight pipe portion 17A, and a downstream side portion that can communicate with the outflow port 3 is formed in the tapered portion 17B that narrows toward the downstream side. .

The port 17 is provided on a pair of support plates 18 extending inward from the inner surface on the tip side of the valve body 10 around the passage valve seat 10A on the inflow port 2 side and the outer surface of the straight pipe section 17A. After applying the bracket 19 continuously provided from the above, the both ends 18 and 19 are connected by the connecting tool (bolts, nuts, etc.) 20, so that the upstream end of the straight pipe portion 17A is made dense on the inner surface of the valve body 10. Fixed. At that time, the length of the port 17 is set so that the downstream side portion of the port 17 is separated from the valve body 10, and thus the passage valve seat portion on the downstream side of the taper portion 17B and on the outflow port 3 side. A separation unit 21 is provided between the separation unit 21 and 10A.

A valve rod (such as a piston rod of a cylinder for opening / closing operation) 22 inserted through the top cover 5 is provided, and the tip of the valve rod 22 is connected to the inner surface of the shutoff valve seat portion 10B via a connecting member 23. It is connected. A communication passage 24 is formed around the port 17.

The operation of the above embodiment will be described below. By pulling and moving the valve body 10 via the valve rod 22 by the operation of the opening / closing cylinder, the passage valve seat portion 10A is opposed to the inflow port 2 and the outflow port 3 as shown in FIG. The ports 2 and 3 can be communicated with each other by the port 17 (opening operation), so that the gas G can flow from the inflow port 2 through the port 17 to the outflow port 3. Also, by pushing and moving the valve body 10 via the valve rod 22, the shutoff valve seat portion 10B can be made to face the inflow port 2 and the outflow port 3 (closing operation), so that the two ports 2 and 3 are shut off. You can

When the valve body 10 is opened and closed with the gas G containing, for example, dust (powder particles) flowing, the valve body 10 and the body liner 4 are opened as shown in FIG.
The gas G containing dust enters the front end space 9 through the gap between and, and the gas G containing dust entering the front end space 9 flows through the front end space 9 and then flows through the separating portion 21. It will be discharged to the outlet 3. Therefore, the amount of dust accumulated in the tip space 9 can be reduced. At that time, the flow of the gas G containing dust in the tip space 9 is smoothly performed toward the separating portion 21 due to the constricted outer surface of the tapered portion 17B.

When the valve body 10 is opened, as shown in FIG. 4, the gas G containing dust is discharged from the taper portion 17B to the outflow port 3. At this time, due to the constricted shape of the taper portion 17B, It is possible to prevent the gas G containing dust from entering (backflowing) into the tip space 9 side or the like through the separating portion 21, and thus preventing dust from entering the tip space 9 side or the like and accumulating.

As the dust-containing gas G flows as described above, dust is contained in the gap between the valve body 10 and the body liner 4 at the inlet portion (FIG. 1) and outlet portion (FIG. 4) of the port 17. The gas G enters and dust is caught by the sliding surface. At this time, both split bodies of the tubular valve body 10 are reduced in size so as to narrow the interval S of the slits 11 against the elastic force of the compression spring 16. Thus valve body 10
Is in a state in which the clearance is automatically adjusted due to its low radial rigidity, so that the sliding surface is damaged by dust, or seizure causes the opening / closing operation of the valve element 11 to become impossible. The push and pull operation force of the valve rod 22 does not become excessive.

Further, when the temperature is lowered at a high temperature,
The valve body 10 is in a state of being embraced by the body liner 4, but at this time, since the valve body 10 becomes smaller due to the slit 11, the pushing / pulling operation force does not become excessive.

The gap between the valve body 10 and the body liner 4 described above can be adjusted by the gap adjusting device 12. That is, by operating the adjusting operation tool 14 to move both elastic biasing tool receiving members 15 toward and away from each other, the two divided bodies can be expanded / contracted so as to change the interval S of the slits 11, and thus the clearance can be adjusted arbitrarily. obtain.

A small amount of dust accumulated in the tip space 9 can be discharged by operating the bolt 7 to remove the bottom cover 6 or the like. At that time, a large amount of dust is hard to accumulate in the tip space 9, The frequency of maintenance can be reduced.

In the above embodiment, the slits 11 are provided at two circumferential positions of the valve body 10, but in the present invention, the slits 11 may be provided at one circumferential position or at three or more circumferential positions. In the above embodiment, the compression spring is used as the elastic biasing member.
Although 16 is shown, an elastic biasing device such as a leaf spring may be used in the present invention.

[0025]

According to the present invention having the above-described structure, the radial rigidity of the valve body can be reduced, whereby the clearance between the valve box and the valve body can be automatically adjusted, and the sliding surface is damaged by dust. In addition, it is possible to prevent the above-mentioned problem and to always perform a smooth opening / closing operation without increasing the pushing / pulling operation force.
Further, the gap between the valve box and the valve body can be positively adjusted by operating the gap adjusting device. Furthermore, when the valve body is held in the valve box side due to a temperature change, the valve body becomes smaller due to the slit, so that the push-pull operation force does not become excessive. Due to these, it is possible to prevent the seizure due to the opening / closing operation (sliding) of the valve. Further, it is possible to prevent dust from excessively accumulating in the valve box and reduce the number of maintenances.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a piston type gate valve according to an embodiment of the present invention.

FIG. 2 is a partially cutaway front view of a valve body of the piston type gate valve.

FIG. 3 is a partially cutaway side view of a valve body of the piston type gate valve.

FIG. 4 is a vertical sectional front view of a gap portion of the piston type gate valve.

FIG. 5 is a vertical sectional front view of a piston type gate valve showing a conventional example.

[Explanation of symbols]

 1 valve box 2 inflow port 3 outflow port 4 body liner 10 valve body 10A passage valve seat part 10B shutoff valve seat part 11 slit 12 gap adjusting device 14 adjusting operation tool 15 elastic biasing device receiving member 16 compression spring (elastic biasing device) ) 17 ports 21 Separation part 22 Valve rod G gas S Slit spacing

Claims (1)

[Claims] 1. A piston type gate valve comprising a valve box having an inlet port and an outlet port, and a valve body provided with a port slidably disposed in the valve box and capable of communicating the both ports. A gap adjustment having an elastic biasing member that separates the downstream side portion of the port from the valve body, provides an axial slit at at least one location in the circumferential direction of the valve body, and widens the interval of this slit. Piston type gate valve characterized by having a device.