JPS6339485Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention relates to a valve, which is particularly installed in the middle of piping for a mixture of powder and gas or a mixture of powder and liquid, and that connects a plate-shaped valve body to the flow path. This relates to a closed type valve that opens and closes a flow path by moving it forward and backward in a direction perpendicular to the flow direction.

Such a valve is installed, for example, in the middle of a piping that transports a flyass through air, but in this case, when the valve is closed, there is a gap of several mm to several hundred mm in front and behind the valve body.
Differential pressures of Ag may occur. At times like this,
If the contact between the valve body and the valve seat is not good, the air on the upstream side will leak, and abrasive powder contained in the air will flow along with the air, causing
The surface of the valve body or valve seat wears out, resulting in loss of valve function.

FIG. 4 shows an example of conventional measures to prevent such a phenomenon. Valve body 1
is inserted into the casing 2 and moved forward and backward by the rod 3 in a direction perpendicular to the direction of the flow path 4 to open and close the flow path 4. The figure shows a state in which a flow path is opened through a hole 5 formed in the valve body 1. Reference numeral 6 denotes a soft packing provided on the valve seat portion 7, and when the flow path 4 is closed due to movement of the valve body 1, the valve seat portion 7 is
This is to prevent leakage of fluid containing powder from the pipe. However, when the soft packing 6 is fixedly fitted to the valve seat part 7 as in this example, the valve body 1
The contact surface of the soft packing 6 gradually wears out due to the reciprocating movement of the soft packing 6, and as a result, the degree of adhesion between the soft packing 6 and the valve body 1 decreases, and the sealing performance is eventually impaired, causing powder to be removed from the gap. Accompanying air blow-through occurs. As a result, the soft packing 6 and the valve body 1
Powder in the air is trapped between the two, and as the valve body 1 is moved back and forth in this state, the wear of the soft packing 6 rapidly progresses. Furthermore, this wear occurs when the valve body 1 slides under a state where a differential pressure acts on the valve body 1 before and after the valve body 1, so the parallelism between the two gradually collapses and the uniformity of the contact surface becomes uneven. is lost, and the degree of adhesion between the two becomes even worse.

The conventional method for eliminating such problems is to configure the valve seat in a wedge shape, and change the position of the wedge-shaped valve seat by tightening bolts according to the wear of the valve seat, so that the valve body and valve are always in contact with each other. There are devices that maintain contact with the seat, but they have a complicated structure, are quite complicated to operate, and have the disadvantage that the entire device is expensive.

The purpose of this invention is to eliminate the drawbacks of the conventional valve devices described above, and by using a relatively simple structure, it is possible to prevent contact between the valve body and the valve seat for valves for fluids carrying powder. It is an object of the present invention to provide a valve that can always maintain uniformity and maintain this uniformity permanently regardless of the degree of wear of the valve seat.

Another object of this invention is to provide a valve that eliminates the influence of gravity on valve operation and has no advantages or disadvantages in valve operation depending on the piping direction.

A further object of this invention is to enable regeneration by performing the minimum possible partial replacement when replacing a worn valve seat with a new one, making the replacement operation simple and easy. The object of the present invention is to provide a valve that can improve economic efficiency.

Still another object of this invention is to prevent powder entrained by passing fluid from entering between the ring-shaped groove that accommodates the valve seat and the valve seat, and to prevent the sliding of the valve seat by the powder. It is an object of the present invention to provide a valve whose surface can be prevented from being worn out.

In order to achieve the above objectives, this invention has a structure in which a plate-shaped valve body is installed in the middle of a pipe through which a mixture of powder and gas or a mixture of powder and liquid flows. In a closed type valve that opens and closes a flow path by moving it forward and backward in a direction perpendicular to the
A valve seat installed opposite the valve body is configured as a ring-shaped valve seat that is disposed in a ring-shaped groove and loosely fitted in the groove so as to be movable back and forth in the direction of the flow path. A plurality of elastic bodies are arranged between the ring-shaped groove and the valve seat to press the valve body evenly against the surface of the valve body, and the contact portion between the valve body and the valve seat is made of a hard body, A force is applied to the ring-shaped valve seat in the direction of pressing it against the surface of the valve body in cooperation with the elastic body, and the mixture flows out between the valve seat and the ring-shaped groove into the groove. The present invention is characterized in that it includes means for press-fitting a fluid into the ring-shaped groove to prevent the fluid from entering the ring-shaped groove.

Next, the structure and operation of the valve of the present invention will be explained in detail based on the drawings showing one embodiment. In Figures 1, 2 and 3, 8
is a valve body with a hole 5 for forming a flow path, and a rod 3
It is caused to advance and retreat in a direction perpendicular to the direction of the flow path 4. Reference numeral 9 denotes a cylindrical valve seat box, which is fitted into the valve seat part 7 on the upstream side of the valve body 8 from the outside of the casing 10, and has a ring-shaped groove 11 that opens inward.
is formed. Reference numeral 12 denotes a ring-shaped valve seat, which is fitted into the groove 11 and is capable of reciprocating movement in the flow path direction within the groove 11 . Reference numeral 13 denotes a spring as an elastic body, one end of which is supported by the bottom of the groove 11 and the other end of which is supported by the bottom of a spring chamber 14 bored in the valve seat 12. A plurality of them are arranged under (in the example shown, eight are arranged). A fixed valve seat 15 is provided at a position facing the valve seat 12 with the valve body 8 in between. The fixed valve seat 15 is also installed from the outside of the casing 10 in the same way as the valve seat box 9 is installed. 16 is an upstream communication pipe, and 17 is a downstream communication pipe. By attaching these communication pipes to each end face of the casing 10, the valve seat box 9 and the fixed valve seat 15 are reliably set in the fixed position. . In the illustrated example, the valve seat on the downstream side is a fixed valve seat 15, and a fixed type valve seat is used. There is absolutely no problem with using the seat. Moreover, it is of course possible to use a fixed type on the upstream side and a reciprocating type on the downstream side.

18 is a hard material bonded to both sides of the valve body 8; 19 is a hard material bonded to the end surface of the valve seat 12;
0 is a hard material bonded to the end face of the fixed valve seat 15, and the hard material 18 is a hard material 1 on each opposing valve seat.
9 to 20, an annular contact portion is realized, and the contact mode is uniform along the circumference. As the hard material mentioned above, it is preferable to use, for example, a super hard metal such as stellite or a hard pottery commonly called ceramic.

Reference numeral 21 denotes an air introduction port, which is connected to the groove 11 and is introduced through an air passage 22 provided in the communication pipe 16. That is, pressurized air from an externally provided pressurized air source (not shown) is introduced in the direction of the arrow through piping a, fills the groove 11, and moves the valve seat 12 in cooperation with the spring 13 to close the valve. A force is applied to the valve seat 12 in the direction of pressing it toward the upstream surface of the body 8. The number of air inlets 21 installed may be one,
Moreover, a plurality of pieces may be used. In this way, valve seat 1
2 toward the valve body 8 is the total force of the spring 13 and the pressure air filling the groove 11, and both of them are applied to the valve seat 1.
2 is pressed uniformly along the contact surface, and so-called uneven contact is prevented from occurring. In addition, there are naturally slight gaps between the inner and outer sliding surfaces of the groove 11 and the valve seat 12, and when pressurized air is blown out of the sliding surfaces from these gaps, the powder in the mixture being handled is This prevents particles such as ash from entering the gap, which contributes to cleaning the sliding surfaces and preventing wear. That is, the pressurized air from the pressurized air source provided in the device of the present invention is transferred to the groove 11.
By introducing the valve into the valve seat, it contributes to achieving uniform coverage of the valve seat and also contributes to maintaining the function of the reciprocating movement of the valve seat.

Furthermore, as shown in FIG. 1, by introducing the pressure air into the seal packing part of the rod 3 through pipe b, the sealing effect of this part can be improved, or by introducing the pressure air into the seal packing part of the rod 3 through pipe c. By introducing it below the casing 10, it can be used for purposes such as assisting the dust removal operation in which the ash accumulated at the bottom of the casing 10 is discharged in the direction of the arrow p, thereby producing a secondary effect.

The valve according to this invention is constructed as described above, and its effects have been described in fragments in the above explanatory text, but to further summarize these, the valve has a relatively simple construction. Therefore, uniform contact between the valve body and the valve seat can be maintained at all times, and this uniformity can be maintained permanently regardless of the degree of wear of the valve seat. In addition, by eliminating the influence of gravity on valve operation, there is no advantage or disadvantage in valve operation depending on the piping direction, and when the valve seat is worn out, it can be replaced with a new one by only partial replacement within the minimum possible range. It enables regeneration, makes the replacement operation simple and easy, and improves economic efficiency. It also prevents powder entrained by the passing fluid from entering between the ring-shaped groove that accommodates the valve seat and the valve seat, and prevents the sliding surface of the valve seat from being worn out by the powder. It has excellent effects such as preventing

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the proposed device, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is an enlarged sectional view of the part in Fig. 1, and Fig. 4 is a sectional view of the conventional device. FIG. 2 is a cross-sectional view of the device. 1, 8... Valve body, 2, 10... Casing, 3
... Rod, 4 ... Channel, 5 ... Hole, 6 ... Soft packing, 7 ... Valve seat, 9 ... Valve seat box, 11 ...
... Groove, 12 ... Valve seat, 13 ... Spring, 14 ... Spring chamber, 15 ... Fixed valve seat, 16, 17 ... Communication pipe, 18, 19, 20 ... Hard material, 21 ... Air Inlet, 22...Air passage, a, b, c...Piping.

Claims (1)

[Scope of utility model registration request] A seal that is installed in the middle of a pipe through which a mixture of powder and gas or a mixture of powder and liquid flows, and opens and closes the flow path by moving a plate-shaped valve body back and forth in a direction perpendicular to the flow path. In this type of valve, the valve seat installed opposite to the valve body is configured as a ring-shaped valve seat that is disposed within a ring-shaped groove and loosely fitted in the groove to enable reciprocating movement in the direction of the flow path. A plurality of elastic bodies are arranged between the ring-shaped groove and the valve seat to evenly press the seat against the surface of the valve body, and the contact portions between the valve body and the valve seat are hard. The ring-shaped valve seat, in cooperation with the elastic body, applies a force that acts in the direction of pressing against the surface of the valve body, and flows out between the valve seat and the ring-shaped groove to cause the mixing. A valve comprising means for pressurizing fluid into the ring-shaped groove to prevent a body from entering the groove.