JPS59140967A - Valve seat for single seat-type ball valve and manufacturing method thereof - Google Patents

Abstract

PURPOSE:To prevent the occurrence of cavitation in a valve in a simple structure by providing a half-cylindrical damping plate having a comblike slit, which faces to S-shaped main path in the valve to be integral therewith a ring-shaped valve seat. CONSTITUTION:A partition wall 4 is disposed in the interior of a valve enclosure 1 to be partitioned into two chambers on inlet 2 side and outlet 3 side, and a ring-shaped valve seat 5 is fixed to an opening 4a of the partition wall 4 through a pressure ring 6. A valve body 7 is disposed opposite to the valve seat 5, and a valve shaft 7a is pierced through a cover 8. In this arrangement, damping plates 10, 11 having a comblike slit 12 are erected at upper and lower end portions of the ring-shaped valve seat 5 extending over the substantially half-peripherys opposed to each other, and the respective damping plates 10, 11 are disposed in the valve enclosure 1 in such a manner as to face to an S-shaped main path. Thus, fluid energy in the valve is damped to prevent cavitation and improve efficiency of outflow.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a single-seat globe valve, and particularly to a valve seat that forms a control section together with a valve body, and a method for manufacturing the same. [Prior Art] Conventionally, this type of single-seat globe valve In globe valves, as a countermeasure against cavitation that occurs inside the valve, a wall made of a perforated cylinder that is integrated with the valve seat is placed around the valve body to prevent fluid from ejecting from the gap between the valve body and the valve seat. It is known that the outflow energy of the fluid is quenched by utilizing the diffusion effect of the facing porous wall surfaces. , and blocks the flow n, which reduces the outflow capacity of the valve, that is, the Cv value, and has the disadvantage that the valve needs to be larger in order to compensate for the lack of valve capacity.

[Summary of the invention]

The present invention has been made in view of these circumstances, and includes a ring-shaped valve seat with a semi-cylindrical damping plate having a comb-shaped slit that screens against the S-shaped main flow path inside the valve. The simple structure of integrally providing the valve can easily and reliably prevent cavitation occurring within the valve, increase the outflow capacity of the valve, and thereby reduce the size of the entire valve. The present invention provides a valve seat for a single-seat globe valve in which a valve seat having a damping plate is obtained by a simple molding process, and a method for lateral advancement thereof.

〔Example〕

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

FIG. 1 shows an embodiment of an instant type globe valve to which the present invention is applied.
Reference numeral 1 denotes a valve housing having a fluid intake 2 and an outlet 3 on the same axis, and a partition wall 4 parallel to the axis and partitioning the inlet 2 and outlet 3 sides into two parts is provided in the center of the valve housing. There is. The partition wall 4Vc is provided with an opening 4a in a direction perpendicular to the axis, and a ring-shaped valve seat 5 having a damping plate that characterizes the present invention, which will be described later, is inserted into the opening 4a via a retaining ring 6. The installation is fixed. Reference numeral 7 denotes a valve body that moves forward and backward from above the valve housing 1 in opposition to the valve seat 5, and its valve stem 7m protrudes to the outside through a lid body 8 fixed to the upper part of the valve housing 1. It is configured so that it can be opened and closed from

Note that 9 in the figure is a holding member that holds the valve body 1 and the valve shaft 7m within the valve housing 1, and supports the valve body 7 slidably through a sleeve 9a.

Now, according to the present invention, in the single-seat globe valve having the above-described configuration, it is possible to take into consideration that the fluid flows as the main flow in a smooth streamline having a substantially S-shape within the valve. The valve is characterized in that a damping plate 10.11 that blocks only the flow is provided using the ring-shaped valve seat 5. In addition, according to the present invention, the main cause of cavitation inside the valve is swirling flow, and to correct this swirling flow, slit-shaped ones are used rather than a large number of pores to improve the outflow efficiency per unit area of the screen plate. The damping plate 10.11 is characterized by having a plurality of comb-like slits 12, taking into consideration the fact that the Cv value can be improved.

In detail, the damping plate 10.11 having the comb-like slit 12 according to the present invention is erected over approximately half the circumference facing each other at the upper and lower end portions of the ring-shaped valve seat 5,
A respective damping plate 10.11 is arranged in the valve housing 1 so as to screen against the S-shaped main flow path within the valve. If such a configuration is used, the damping plates io, i
10 to attenuate the fluid energy flowing within the valve,
Cavitation can be easily and appropriately prevented, and the outflow efficiency can be improved compared to the conventional method, thereby making it possible to properly rectify the fluid and significantly improve the Cv value. Therefore, the method according to the present invention is effective in reducing the overall size of the valve.

Here, the molding process of the valve seat 5 having the above-mentioned damping ridges 10 and 11 at its upper and lower ends will be described in detail.First, as shown in FIG. A member consisting of a cylindrical wall 14 connected to the cylindrical wall 14 is prepared, and a plurality of slits 12 are formed in the centripetal direction at predetermined intervals over the entire circumference of the cylindrical wall 14. Next, in the same figure (
As shown in (b), it is divided into two parts along the axial direction, and then one of the parts is inverted and reconnected by welding or the like at the ring-shaped body 13 as shown in (c) of the same figure. and,
The thus recombined members are machined by machining the portion shown by the dashed line in FIG. is completed.

By using such a method, the entire molding process is easier than when machining the entire cylindrical member or attaching a semi-cylindrical damping plate with slits 12 to the ring-shaped valve seat. It has the advantage that it can be carried out reliably and is superior in terms of strength.

Note that the present invention is not limited to the structure of the embodiment described above;
It goes without saying that the shape, structure, etc. of each part can be modified and changed as appropriate. For example, in the embodiment described above, the ring-shaped valve seats 5 facing each other have damping plates 10 and 11 at their lower ends.
Although the present invention is not limited to this, it is easy to understand that the same effect can be obtained even if only one of the damping plates 10 and 11 is provided. Goodbye 1. Furthermore, it goes without saying that similar effects can be obtained even when the fluid inside the valve flows in the opposite direction to that shown in FIG.

〔Effect of the invention〕

As explained above, according to the present invention, a semi-cylindrical damping plate having a comb-like slit that screens against the S-shaped main flow path in the valve is integrally provided on a ring-shaped valve seat. As a result, despite the simple configuration, it is possible to prevent the occurrence of cavitation within the valve and increase the outflow capacity of the valve, thereby achieving various advantages such as miniaturization of the entire valve. It has a great effect.

Further, according to the present invention, when the semi-cylindrical damping plates are provided at the upper and lower ends of the ring-shaped valve seat so as to face each other, the ring-shaped body and the cylindrical wall formed with the slits formed on the entire circumference can be used. Since the valve seat is formed by dividing a member into two parts, inverting one part, and recombining them, it is possible to obtain a valve seat having a damping plate with excellent strength despite being a simple and inexpensive method. It has the effect of being able to.

[Brief explanation of the drawing]

Fig. 1 is a schematic sectional view showing an embodiment of a single-seat globe valve to which the present invention is applied, Figs. 2 (a), (b), (c) and 3 have damping plates at both upper and lower ends. It is a schematic perspective view and a side sectional view explaining the manufacturing method of a valve seat. 1... Valve housing, 4... Partition wall, 5... Ring-shaped valve seat, 1... Valve body, 10, 11... Damping plate, 12... slit. Patent applicant Yamatake Honeywell Co., Ltd. Agent Masaki Yamakawa (and one other person) Figure 1 Figure 3 Figure 2 Figure 2

Claims (3)

[Claims] (1) A damping plate having a comb-like slit that screens against the S-shaped main flow path inside the valve is provided over approximately half the circumference of the ring-shaped valve seat that is attached to the intermediate partition wall inside the valve. Valve seat for single-seat globe valve. (2) Damping having comb-shaped slits that screen against the S-shaped main flow path inside the valve over approximately half the circumference facing each other at the upper and lower ends of the ring-shaped valve seat attached to the intermediate partition wall inside the valve. A valve seat for a single-seat globe valve, characterized by the provision of a plate. (3) providing a cylindrical wall at one end of the ring-shaped valve seat, forming a plurality of slits all around the cylindrical wall, and then dividing the valve seat and the cylindrical wall into two along the axial direction; A method for manufacturing a valve seat for a single-seat globe valve, characterized by inverting one side and reconnecting at the valve seat part.