JP2005265032A - Seat structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems that the function capable of supplying a large volume of high pressure gas is demanded for a high pressure vessel; valve in a short time; the high pressure vessel valve having a flow coefficient Cv applicable for the system does not come in practice; and the automation of a flow control is greatly needed. <P>SOLUTION: The problems can be solved by comprising a seat structure having (1) a projection of a circular truncated cone shape (sommma shape) having a recess of a in height, and D in diameter with a recess of b in depth, and having a top end r surface is formed in a seal part of a seat disk forming the seal part at a drain cock 1 side. (2) In the seal part of the seat disk 5 placed in contact with a valve main body side 3, a contact diameter D and the diameter d of a gas flow inlet 2 of the valve main body 3 are always D>d. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a structure of a seat portion that is a component of a high-pressure vessel valve.

In recent years, gas piping systems using various high-pressure gases have become sophisticated and highly functional. A typical example is noticeable in semiconductor manufacturing systems. That is, in order to clean the entire piping system, the high-pressure vessel valve has been required to have a function of flowing a large amount of gas in a short time.

    This function is expressed by a “flow coefficient” Cv value of the high-pressure vessel valve and is a capability value with respect to the flow rate of the vessel valve. (Equation 1) shows the formula for calculating the Cv value.

The magnitude of Cv indicates the flow capacity of the high-pressure vessel valve that can be handled instantaneously. In other words, it can be said to represent the capacity of the high-pressure vessel valve.

  A high pressure vessel valve having a large Cv value has been requested not only from the semiconductor manufacturing industry but also from the general-purpose high-pressure gas demand industry.

    An external view of the currently used high-pressure vessel valve is shown in (FIG. 1), and an enlarged view of a seal portion considered to dominate the Cv value is shown in (FIG. 2).

    The tip of the kerep 1 is fitted into the gas inlet 2 of the valve body 3 at an angle θ. It is designed so that a relationship of D> d is established between the diameter D of the tip portion of the Kellep 1 and the diameter d of the gas inlet 2.

    Table 1 shows the results of an experiment in which the insertion angle θ of the tip portion (the shape of the truncated cone) of the Kelepp 1 was variously changed.

    As the insertion angle θ at the tip of the working high-pressure vessel valve Kelep 1 becomes smaller than the working angle 45 °, the Cv value becomes smaller and tends to be contrary to the purpose.

When θ is increased, the Cv value increases, and it has been found that a very good Cv value can be obtained at θ = 90 °.
Japanese Patent Application No. 2004-13912

The market demand for the ability of high pressure vessel valves to handle flow is becoming increasingly severe. The Cv value representing the flow capacity capability is about 2.5.

In order to meet market demands, it is necessary to develop a “seal part structure” that can secure a Cv value of 3.0 or more, and to put into practical use a high-pressure vessel valve that is commonly equipped with this “seal part structure”.

1) Solution from shape and structure The details of the structure 4a of the seal portion shown in the general view (FIG. 2) of the high-pressure vessel valve according to the present invention are shown in FIG.

The valve seat portion has a structure in which the Kerep side seal portion 5 is separated from the Kerep body 1. The Kelep side seal portion having the separation structure will be referred to as a seat desk 5 in the future. The Kelep body 1 and the seat desk portion 5 are joined by a cold caulking method, a shrink fitting, a cold fitting method, or the like.

The structural features of the present invention are shown below.
A) A frustoconical protrusion (an outer ring mountain shape) having a height “a” having a depth “b” and a diameter “D” and having a tip r surface is formed on the seal portion of the seat desk 5. In addition, the hollow bottom shape is not specified. There are optimal a, b, b / a and r values for Cv values.
B) The protrusion is formed at an angle ω. There is an optimal ω for the Cv value.
C) The seal portion of the seat desk 5 that contacts the valve body side 3 always has a contact diameter D and a diameter of the gas inlet 2 of the valve body 3 larger than D> d. There is an optimum D / d for the Cv value.
D) The surface finish of the contact portion between the seal portion of the seat desk 5 and the seal portion of the valve body 3 is finished with an accuracy according to the application.

2) Examination from the viewpoint of material a) The hardness of the seat desk 5 ≦ the hardness of the seal part on the valve body 3 side in principle.
B) For gases that are particularly corrosive, select materials that have no difference in pitting potential.
C) The following materials having low hardness and good corrosion resistance are suitable.
D) Nickel 200 or Nickel 201 is preferable as the material for the seat desk 5.

In the container valve structure of the present invention, there is a great novelty in the Kelep structure constituting the valve seat portion. This structure can be achieved by detailed examination of material, heat treatment and construction method.

    By using the seat portion structure of the present invention, the Cv value of the high-pressure vessel valve can be improved. As a result, when supplying high-pressure gas to various systems, a large volume of gas can be supplied in a short time, enabling efficient cleaning, and a significant improvement in productivity can be expected.

In addition, by finding this structure, it became possible to obtain airtightness with a smaller thrust, and therefore automatic opening / closing was possible by mounting an automatic opening / closing operation mechanism and actuator using pneumatic pressure. Remote automatic operation can dispel the sense of safety about the manual opening / closing operation of the operator who uses this container valve, and can avoid any damage.

The present invention was verified with a high-pressure vessel valve using a seat portion structure manufactured according to the present invention. The details will be described below.

The shape of the seat desk part is (FIG. 4), the diameter D of the contact circle D = 5 ± 0.05 mm, the depth b of the depression b = 0.4 + 0.1-0 mm, and the seal part r = 0.2 mm (0. 8S), the seal portion angle ω = 60 °, and the diameter d of the gas inflow hole of the valve body constituting the seal portion was set to 4 mm.

The seat desk 5 has a different structure from the main body of Kerep for the purpose of ensuring the confidentiality of the seal portion. Of course, it is needless to say that the present invention also includes an example in which the structure is integrated with Kellep.

The seat desk 5 has carbon = 0.02% for the purpose of ensuring corrosion resistance and sealing.
Nickel = 99.5% NICKEL201 was used. The HV hardness was adjusted to 80 to 100 by annealing, and the fitting was integrated with the Kelep body by quenching. The functional characteristics as a high-pressure vessel valve using the seat part structure of the present invention will be described below.

    Table 1 shows the Cv value of the high-pressure vessel valve using the seat structure of the present invention compared with the Cv value of the conventional vessel valve measured under the same conditions.

           The Cv values of the container valves 1 to 5 of the present invention all reach approximately 1.5 times that of the conventional container valve. This Cv value is an epoch-making value in the container valve industry.

The durability of the container valve was evaluated based on the concept of this design, and the results are shown in Table 2.

The durability of the container valve of the present invention far exceeds the conventional container valve measured under the same conditions. This proves that the design concept of the present invention is not only excellent in Cv value but also excellent in providing a container valve that is excellent in terms of durability. Note that the minimum operating pressure of the actuator was approximately equal to 0.38 to 0.43 MPa for the container valve of the present invention, compared to 0.4 MPa for the conventional container valve.

    In the future, not only the semiconductor manufacturing industry but also the high pressure vessel valve demand industry will continue to pursue high productivity, and it goes without saying that a system that is much more productive than conventional devices is incorporated.

    Under such a trend, automatic control technology for flow rate control using a container valve is being realized. The high-pressure vessel valve incorporating the seat portion structure of the present invention plays an essential and important role in the process and greatly contributes to the development of the industry.

It is explanatory drawing which shows the outline | summary of the implementation method of the working high pressure vessel valve.

It is explanatory drawing which shows the detail of the sheet | seat part structure of the working high pressure vessel valve.

It is explanatory drawing which shows the outline | summary of the implementation method of the high pressure vessel valve by this invention.

It is explanatory drawing which shows the detail of the sheet | seat part structure of the high pressure vessel valve by this invention.

Explanation of symbols

1. Kerep 2. Gas inlet 3. Valve body 4. Sealing part of the current high pressure vessel valve 4a. Sealing part of high-pressure vessel valve according to the present invention 5. Seat desk

Claims (6)

  A seat part structure for a high-pressure container valve, characterized in that a frustoconical projection having a minimum diameter larger than the gas inlet diameter of the container valve body is formed in the kelp part seat part. A seat part structure for a high-pressure vessel valve, wherein an arbitrary circular recess is formed on the plane of the projection of the truncated cone according to claim 1 to form an outer ring mountain shape.   A seat part structure for a high-pressure vessel valve, characterized in that a smooth R surface is formed at the tip of the outer ring-shaped projection part according to claim 2.   A seat part structure for a high-pressure vessel valve, wherein the seat part structure (seat desk) according to any one of claims 1 to 3 is inserted into a kerep. The seat part structure of a high-pressure container valve, wherein the hardness of the seat part structure according to claim 4 is smaller than the hardness of the container valve body.   6. The seat part structure of a high-pressure vessel valve according to claim 1, wherein a Cv value of 3 or more can be secured.

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