JP3013188B2 - Diaphragm valve and method of manufacturing diaphragm - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a high-performance diaphragm valve used in a semiconductor gas process or the like, and its performance is improved by using a cobalt or nickel-based superalloy for the diaphragm. It provides an improvement.

[Summary of the Invention]

According to the present invention, in a diaphragm applied to a diaphragm valve, baking can be performed at a high temperature of 150 ° C. or higher by using a material K of the diaphragm or a nickel-based superalloy, and a gas pressure of 150 kg / cm ² or higher. The purpose of the present invention is to obtain a high-performance diaphragm valve that can be used even in a corrosive gas.

[Conventional technology]

Conventionally, as a diaphragm valve used for a gas in a semiconductor process or the like, as shown in a sectional view of FIG. 1, a material of a diaphragm 3 is a precipitation hardening type stainless steel, a nickel alloy such as Inconel, or the like.

[Problems to be solved by the invention]

However, these samples have insufficient strength such as hardness and tensile strength, and cannot be used when used for high pressures of 150 kg / cm ² or more. There was a drawback that it could not be used for corrosive gas because of its poor properties.

Therefore, the present invention solves such a conventional drawback, and
An object of the present invention is to obtain a high-performance metal diaphragm valve that has a long life even when used at a high pressure of g / cm ² or more and can be used for corrosive gas.

[Means for solving the problem]

In order to solve the above problems, the present invention has a composition range of 30 to 50% for cobalt, 10 to 20% for nickel, 5 to 20% for chromium, 3 to 5% for tungsten, and 3 to 15% for molybdenum.
%, Composed of a cobalt-based superalloy that becomes the remaining iron, or whose composition range is 25-45% cobalt, 12-25% nickel
An object of the present invention is to provide a diaphragm valve using a diaphragm made of molybdenum 8 to 15%, niobium 0.1 to 3%, and a nickel-based superalloy to be nickel.

(Operation)

When the above super alloy is used, the hardness and tensile strength are high,
Even when used under a high pressure of 150 kg / cm ² or more, it has a long life and can be used for corrosive gases, so that a high-performance diaphragm valve can be obtained.

〔Example〕

An embodiment of the present invention will be described below with reference to the cross-sectional view of FIG.

In FIG. 1, a cylindrical metal, ceramics, or polymer valve seat sheet block 1 is inserted into a stainless steel valve case 2.

The outer peripheral end 1a of this seat block has a convex cross section on both the upper and lower surfaces. The upper convex portion contacts the diaphragm 3 and the lower convex portion contacts the valve case 2 and is pressed by the press-contact screw 4 so as to be in contact with the outside. Sealing is taking place. The inner peripheral end 1b of the seat block also has a convex cross section on both the upper and lower surfaces. The lower convex portion is pressed by the valve case 2 to perform sealing with the outside, and the upper convex portion is integrated with the diaphragm 3. The stem 5 is pressed by the downward movement, and the supply and cutoff of the gas is controlled by the vertical movement of the stem 5. The surface of the diaphragm 3 is constantly subjected to gas pressure, and the diaphragm 3 is repeatedly deformed to supply and shut off the gas. In addition, since baking is performed at a high temperature of 150 ° C. or more, it is required that the strength of the diaphragm does not decrease and that the amount of released gas is small. In the case of corrosive gas, the diaphragm is not corroded,
It is necessary that reliability is not impaired. Also, due to the contact wear between the diaphragm and the sheet block, the wear resistance of the surface of the diaphragm and the generation of particles are prevented,
Smoothness is also required. The composition range of this diaphragm is 30-50% cobalt, 10-20% nickel, 5-20% chromium,
Tungsten 3-5%, molybdenum 3-15%, cobalt-based superalloy of remaining iron or cobalt 25-45%, chromium 12
~ 25%, molybdenum 8 ~ 15%, niobium 0.1 ~ 3%, nickel-base superalloy of nickel remaining is vacuum-melted to high cleanliness, cold-working rate 70 ~ 90%, 0.1 ~ 0.3mm thickness When a strip is punched out into a disk shape by press punching, surface polished, and vacuum heat treated at 400 ° C to 700 ° C, a higher pressure than conventional precipitation hardening stainless steel or nickel alloys such as Inconel can be used. It has a long life and can be used for corrosive gases. A performance comparison between the above-described metal diaphragm according to the present invention and a conventional one was conducted. As a result, as shown in the characteristic diagram of FIG. 2, when a cobalt-based superalloy or a nickel-based superalloy is used, the life is greatly improved even under a high pressure as compared with a conventional product. In some cases, a marked improvement is observed.

Further, as shown in the comparative diagram of FIG. 3, the durability against corrosive gas is greatly improved as compared with the conventional product, and particularly in the case of a nickel-base superalloy, it is effective against all corrosive gases. .

〔The invention's effect〕

The invention as described above, the diaphragm diaphragm cobalt-based valve, or, by using a super nickel based alloy, a high temperature baking or 0.99 ° C. is also possible, also be used for 150 kg / cm ² higher than the pressure In addition, it enables the completion of high-performance valves that can be used for corrosive gases,
As a result, the performance of an ultra-high purity gas supply system used in a semiconductor process or the like is significantly improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a metal diaphragm valve using a diaphragm according to the present invention, FIG. 2 is a characteristic diagram comparing the operating gas pressure and the number of times of opening and closing, and FIG. It is a comparative figure showing the degree of corrosion when immersed in 100% of various gases.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ identification code FI F16K 7/12 F16K 7/12 A (58) Investigated field (Int.Cl. ⁷ , DB name) C22C 19/07 F C22C 19 / 03 F F16K 7/12 A C22F 1/00 A C22F 1/10 J C22C 30/00

Claims (6)

(57) [Claims] The composition range of the diaphragm is cobalt 30-50.
%, Nickel: 10 to 20%, chromium: 5 to 20%, tungsten: 3 to 5%, molybdenum: 3 to 15%, and a diaphragm made of a cobalt-based superalloy to be the remaining iron. 2. The composition range of the diaphragm is 25 to 45 cobalt.
%, Nickel 12-25%, molybdenum 8-15%, niobium 0.
A diaphragm valve using a diaphragm made of a nickel-based superalloy consisting of 1 to 3% and nickel of 12 to 54.9%. 3. The composition range is from 30 to 50% cobalt and 10% nickel.
A diaphragm comprising a cobalt-based superalloy of about 20%, 5-20% of chromium, 3-5% of tungsten, 3-15% of molybdenum, and the remaining iron. 4. The composition range is from 25 to 45% cobalt and 12 to chromium.
A diaphragm comprising a nickel-based superalloy comprising 25%, 8-15% molybdenum, 0.1-3% niobium, and 12-54.9% nickel. 5. A composition range of 30 to 50% of cobalt and 10% of nickel.
~ 20%, chromium 5 ~ 20%, tungsten 3 ~ 5%, molybdenum 3 ~ 15%, cobalt-based superalloy which will be the remaining iron is vacuum-melted, and the strip is subjected to a cold working rate of 70 ~ 90%, A method for manufacturing a diaphragm, comprising the steps of punching out a disk by pressing, polishing the surface, and performing vacuum heat treatment. 6. A composition range of 25 to 45% cobalt and 12 to chromium.
25%, molybdenum 8 ~ 15%, niobium 0.1 ~ 3%, nickel 12 ~ 54.9% nickel base super alloy consisting of vacuum melting,
A method for manufacturing a diaphragm, comprising steps of forming a strip having a cold working rate of 70 to 90%, punching it into a disk shape by press punching, polishing the surface, and performing vacuum heat treatment.