JPS59155675A - Regulation valve for collecting steam - Google Patents

Abstract

PURPOSE:To obtain a regulation valve for collecting steam while requiring no maintenance by inserting an annular scraper contacting tangentially with a plug at the end of cylindrical guide member facing against the valve seat. CONSTITUTION:A plug 6 will move retreatably from above a valve body 1 while facing with a valve seat 4 and supported slidably by means of a tubular guide member 8. An annular scraper 15 contacting tangentially with the edge section of large diameter section 11 of plug 6 for scratching scale deposited on the large diameter section 11 by means of edge section 15a at the lower end is arranged at the lower end of guide member 8 and inserted into the guide member 8 by a cap member 16.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a steam recovery control valve suitable for use in a turbine boiler system or the like.

[Prior art]

Generally, the high-pressure steam used to rotate the X wheel of a turbine used for power generation, etc., still has high-temperature energy that remains after the jet energy is consumed, so it has traditionally been the case that this is used to preheat the steam. It has been carried out since. That is, the steam that has been converted into drains due to the heat exchange action is vaporized again and used to rotate the turbine blades. By the way, in the process of boiler systems in which effective use of thermal energy is essential, iron oxide is the main component in the control valve used for 1NJ control of the drain. A problem arises in that a scale-like substance, so-called "water scale", is deposited and adheres particularly to the stagnation parts of the valve internal parts, which obstructs the operation of the valve.

That is, conventional control valves for steam recovery of this type include those using gate valves and those using rotary valves.
Basically, a scraper is fixedly installed on the drive path of the inner valve, and this scraper scrapes off any deposits on the seating surface of the inner valve at once.

In order to extend the life of this scraper function, a spring is used to provide tension9, and the scraper itself is made of a leaf spring.

However, all of these ideas are still in the very early stages of installing a scraper only in the area where the largest amount of water scale is deposited, and the internal pressure of the valve acts on the precipitated scale to forcibly scrape off the firmly and thickly adhered water scale. However, because of the fact that they are used as equipment, they are subject to wear and tear and damage to the cranes, and they are forced to work hard to maintain them.

[Summary of the invention]

The present invention was made in view of these circumstances, and
a cylindrical plug having a large diameter portion and a small diameter portion separated by a band-shaped seat formed in the intermediate portion; a cylindrical guide member fixed to a valve body so as to guide the large diameter portion of the plug;
7j having a stepped inner hole into which the small diameter portion of the plug is fitted;
The small diameter portion of the plug is provided on the same axis as the L-shaped valve seat, and a plurality of elongated slits having the same width are provided in the small diameter portion of the plug and reach the point closest to the seating portion from the end of the plug. By reciprocating in the axial direction from the outside of the valve body to increase or decrease the opening area of the slit, the flow rate can be controlled. By inserting an annular scraper into the valve, despite the simple structure, you can simply select the type of valve and make improvements based on the characteristics of the flow lines of the fluid inside the valve, eliminating the troublesome maintenance required in the past. The present invention provides a control valve for recovering unnecessary steam.

〔Example〕

Hereinafter, the present invention will be illustrated in the drawings, and an embodiment will be explained in detail.In the drawings, first, the overall valve configuration will be briefly described. In this embodiment, an angle valve is shown in which the inlet 2 and the outlet 3 are formed in a direction perpendicular to each other. 4 is an annular valve seat 6 screwed into an opening 5 formed in a partition that partitions the inlet 2 and the outlet 3;
is a plug that moves forward and backward from above the valve body 1 in opposition to the valve seat 4, and is fitted into an open lower hole bored in the upper part of the valve body 1 so as to be located on the same axis as the valve seat 4. The valve shaft 6a is slidably supported by a cylindrical guide member 8 and can be externally operated by passing through an upper cover 9 fixed to the upper part of the valve body 1.

Now, according to the present invention, the above-mentioned valve seat 4, plug 6, and guide part 8 are constructed as follows. That is, the plug 6 is divided into an upper large-diameter part 11 and a lower blade small-diameter part 12 by a band-shaped seat part 10 formed in the central part in the axial direction, and this small-diameter part 12 includes A plurality of elongated slits 13 having the same width μ are formed in the circumferential direction from the lower end to the closest point of the seating portion 10. That is, both side edges of this slit 13 are formed parallel to each other. The valve seat 4 has a small-diameter portion 14a at its upper end inner wall on the plug 6 side, and a stepped inner hole 14 formed at its lower side with a predetermined gap 14b between it and the plug i. It is formed to have. The plug 6 is reciprocated from the outside of the valve body 1 in the @ line direction to increase or decrease the opening area of the slit 13 at the threshold with the valve seat 4, thereby controlling the upflow overflow amount. .

Further, at the lower end of the guide member 8, an edge portion 15 is provided which circumscribes the @edge portion of the large diameter portion 11 of the plug 6 and is located at the lower end thereof.
An annular scraper 15 for scraping away precipitated scale attached to the large-diameter portion 11 is provided, and is attached to the guide member 8 by being fitted with a cap member 16.

Now, in the control valve having the above-mentioned configuration, the major portion where precipitated scale such as water scale is deposited inside the control valve is separated into at least two locations. That is, one of them is a wall portion, that is, the inner hole 14 of the valve seat 4, where the pressure immediately downstream of the fluid contraction portion rapidly recovers. The other one is the outer wall of the large-diameter portion 11 of the plug 6 that appears between the valve seat 4 and the guide member 8, that is, the belly portion of the plug 6 that receives direct impact from the fluid.

According to the present invention having the above-described configuration, the contact surface of the valve seat 4 with the plug 6 is the small diameter portion 14a of the inner hole 14 of the valve seat 4, and the sliding contact surface of the plug 6 with the valve seat 4 is the small diameter portion 14a of the inner hole 14 of the valve seat 4. teeth,
Except for the slit 13 in the skirt portion, it is limited to the hanging portion in the ζ-axis direction, and all of them are in contact where the narrow portions intersect in a cross. That is, several points of intersection are scattered around the inner hole 14 of the valve seat 4 with a minimum area. The contact area hardly changes even when the plug 6 moves, and the contact point does not move.

Therefore, there is no room for water scale to adhere to this point, and even if it does, the adhesion area is small and the adhesion force is relatively small, so it can be easily scraped off by the small diameter portion 14a of the valve seat 4 by driving the plug 6. It is something that

Next, the guide member 8 is hung down in the axial direction along the outer wall of the large diameter portion 11 of the plug 6, and a scraper 15 provided at the end of the guide member 8, which is water scale with relatively strong adhesion that is deposited by fluid collision, is removed. However, it is effectively scraped off at the entrance and exit port where the plug 6 is drawn in and pulled out by the reciprocating action of the plug 6, and water scale is not trapped in the gap between the plug 6 and the guide member 8.

It should be noted that the present invention is not limited to the structure of the embodiment described above, and the shape and structure of each part can be modified and changed as appropriate, and it goes without saying that the valve structure is not limited to the angle valve in the embodiment.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to prevent enlargement of deposited scale by dividing the scale deposition part into two parts depending on the cause and using optimal means for each part, which is also advantageous in terms of valve manufacturing. Further, there is an excellent effect that the valve can always operate appropriately. In addition, according to the present invention, improvements can be made based on the selection of the type of valve and the characteristics of the flow lines of the fluid inside the valve.
There is an advantage that a valve that does not require troublesome maintenance or the like can be easily obtained.

[Brief explanation of the drawing]

The figure shows an embodiment of the steam recovery control valve according to the present invention,
The first part is a vertical sectional view showing the overall general structure, the second part is an enlarged view of the main part, and the third part is an enlarged view of part A in FIG. 2. ...Inflow port, 3...Outlet port, 4...Valve seat, 6...Plug, 8...Guide member, 10...Seating portion, 11... large diameter part,
12...Small diameter part, 13...Slit, 14...
...Stepped inner hole, 15...Annular scraper. Patent applicant Yamatake Honeywell Co., Ltd. Tokyo Shibaura Electric Co., Ltd. Agent Masaki Yamakawa (1 person)

Claims (1)

[Claims] A cylindrical plug with a large diameter portion and a small diameter portion separated by a band-shaped M seat portion formed in the middle portion, and a cylindrical guide member fixed to the valve body so as to guide the large diameter portion of the plug, An annular valve seat having a stepped inner hole into which the small diameter portion of the plug is fitted is provided on the same axis. A plurality of fg4+ long slits of the same width are provided, and this plug is reciprocated in the axial direction from the outside of the valve body to increase or decrease the opening area of the slit, thereby achieving flow-through and elongation. A control valve for steam recovery, characterized in that an annular scraper circumscribing the plug is fitted into an end of the guide member facing the valve seat side.