JP4545612B2 - High heat resistant gasket and manufacturing method thereof - Google Patents

Description

  The present invention relates to a high heat resistant gasket, in particular, a metal jacket type high heat resistant gasket that can withstand use at a high temperature of 900 ° C. or higher, and a method for manufacturing the same.

  In order to save energy, the industry is trying to develop high-temperature air combustion technology and its exhaust heat recovery, energy equipment efficiency, and incineration equipment using waste plastic. In this case, the higher the operating temperature, the more efficiently the energy can be used, and the generation temperature of the dioxin generated at a low temperature is greatly reduced at a high temperature of 800 ° C. or higher. Higher temperatures are required, but the heat resistance of gaskets is a bottleneck in all facilities.

  Conventionally, as a high-temperature gasket or heat-resistant gasket, alumina silica fiber is made into a paper shape, and this is fixed to a metal thin plate such as stainless steel or low carbon rolled steel (SPC) with a nail by mechanical bonding or adhesive (for example, JP-A-11-315930), a metal jacket type gasket in which a board made of alumina fiber is wrapped with a metal jacket, or an expanded graphite sheet is laminated, and this is wrapped with a metal plate. A metal wrapping gasket (for example, Japanese Utility Model Laid-Open No. 5-38464) in which a mica sheet is laminated between the surfaces facing the sheet is known.

  However, since the alumina silica fiber paper is thin and easily damaged, the sealing performance is poor, and when the surface pressure is increased, there is a problem that the pressure is lost at high pressure and the seal is broken. In addition, when the adhesive is an organic adhesive, there is a problem that it cannot be used at a high temperature because an inorganic adhesive such as water glass melts at a high temperature.

  On the other hand, a board made only of alumina silica fiber or alumina fiber is durable at high temperature, but is very expensive. If this is used as a metal jacket type gasket as an internal material and a high surface pressure is applied, there are many fibers. Therefore, it is destroyed at a high temperature and the sealing performance is deteriorated. Moreover, since the metal jacket is formed of stainless steel such as SUS304, there is a problem that pitting corrosion occurs at a high temperature of 600 to 750 ° C. and lacks durability. In addition, the board made of only alumina silica fiber or alumina fiber is not only very expensive, but also has a problem that the handleability during the manufacturing process is poor and the blade is significantly damaged when it is cut into a predetermined shape.

  Therefore, at present, there is no high heat-resistant gasket having good sealing performance and excellent durability at temperatures exceeding 900 ° C.

JP 11-315930 A Japanese Utility Model Publication No. 5-38464

  It is an object of the present invention to obtain a high heat-resistant gasket that has good sealing properties, excellent durability, can be used at a temperature of 900 ° C. or more, is easy to handle in the manufacturing process, and is inexpensive.

  In the present invention, as means for solving the above-mentioned problems, fine inorganic fibers such as alumina silica fibers and alumina fibers and clay mineral fine fibers having a fire resistance of 1300 ° C. or higher, such as sepiolite (hydrous magnesium silicate), etc. By adding 5-30% inorganic short fibers, the amount of inorganic long fibers used is reduced to 60% or less to reduce costs, while at the same time preventing wear of the Thomson blade when punching the inorganic fiber board into a predetermined shape. 20-50% of inorganic fine powder is added, and the density of the inorganic fiber board is made uniform by utilizing the elasticity of the fine powder, and the load applied to the inorganic long fiber is dispersed to make the sealing property at high temperature uniform. Thus, the surface pressure can be increased while a heat-resistant and corrosion-resistant alloy is used as the jacket material.

That is, the present invention is 10 to 60% high heat resistant inorganic long fibers having a fiber length of 2 to 40 mm, 5 to 20% high heat resistant inorganic short fibers having a fiber length of less than 1 mm, and an average particle size of 0.1 %. An inorganic fiber sheet comprising 30 to 80 % of inorganic fine powder of 10 to 80 μm and comprising a composition in which the total of the high heat-resistant inorganic long fibers and the high heat-resistant inorganic short fibers is 20 to 70 %, The present invention provides a metal jacket type high heat resistant gasket formed by coating with a metal jacket made of an alloy.

  In a preferred embodiment, a high chromium high nickel low carbon stainless steel containing 15 to 30% Cr, 10 to 80% Ni, and 0.4% or less C is used as the heat and corrosion resistant alloy forming the metal jacket. In another embodiment, a nickel-based heat-resistant alloy comprising Cr 15-30% and Ni 10-80% is employed as the heat-resistant and corrosion-resistant alloy. In other words, the reason why pitting corrosion occurs in the metal jacket is that water vapor and chlorine gas generated from the internal material exist in the metal jacket at high temperature and high pressure, and at the same time, this pitting corrosion is caused by the amount of Cr in the steel. It is hard to get up as the amount of carbon increases, it is harder to get up as the amount of carbon decreases, and it becomes harder to get up as the amount of nickel increases, and at the same time, it is affected by the amount of Mo added for the purpose of improving the properties of steel. Therefore, the high chromium, high nickel, low carbon stainless steel or nickel base heat-resistant alloy is adopted as the jacket material.

  In a preferred embodiment, the metal jacket type high heat resistant gasket is a metal jacket type gasket formed by coating an inorganic fiber sheet with a metal jacket, and the inorganic fiber sheet has a temperature of 1300 ° C. or higher, preferably 1400 ° C. or higher. High heat-resistant inorganic long fibers having a maximum use temperature of 10 to 60% and 1300 ° C or higher, preferably 5 to 20% high heat-resistant inorganic short fibers having a maximum use temperature of 1400 ° C or higher and 1300 ° C or higher, preferably Is composed of 30 to 80% inorganic fine powder having a melting point of 1400 ° C. or higher, and the total of the high heat resistant inorganic long fibers and the high heat resistant inorganic short fibers is 20 to 70%. is there.

  In a preferred embodiment, the inorganic fiber sheet is a sheet containing 5% or less of an inorganic binder having a melting point of 1300 ° C. or higher, preferably 1400 ° C. or higher, in addition to the above components.

  As the high heat resistant inorganic long fiber, any inorganic long fiber can be used as long as the maximum use temperature is 1300 ° C. or higher, and preferably 1400 ° C. or higher. Typical examples thereof include alumina silica fiber and alumina. A fiber, a boron fiber, a carbon fiber, etc. are mentioned, These can be used individually or in combination. Commercially available products include, for example, Finex (registered trademark) manufactured by Nichias Corporation, Ruby (registered trademark), Denka Arsene (trade name) manufactured by Denki Kagaku Kogyo Co., Ltd., Isowool (registered trademark) 1400, 1500, 1600, Nichibi Corporation's alumina fiber Nichibi Alf (registered trademark), and the like. In addition, it is suitable to use the said high heat resistant inorganic continuous fiber with a small fiber diameter, for example, a fiber diameter of 0.2-12 micrometers, Preferably, it is 0.2-7 micrometers. Further, the longer the fiber length of the inorganic long fiber, the better the handleability and sheet strength in the process of producing the inorganic fiber sheet, but it is sufficient that the average fiber length is 1 mm or more. In the range of 2 mm to 40 mm. In addition, the inorganic long fibers may be either amorphous or crystalline, but from the viewpoint of heat resistance, it is preferable to use a crystalline one having a high maximum use temperature.

  The high heat-resistant inorganic short fiber is added for the purpose of reducing the cost of the inorganic fiber board and at the same time preventing the wear of the Thomson blade when the inorganic fiber board is punched into a predetermined shape. Fine fibers of clay mineral (magnesium silicate ore) having the above fire resistance, for example, it is preferable to use inorganic short fibers such as sepiolite (hydrous magnesium silicate), short fibers of the same material as the inorganic long fibers, for example, Alumina-silica short fiber, alumina short fiber, boron fiber, carbon fiber and the like can be used alone or in combination. Commercially available products include Hayashi Kasei Co., Ltd.'s Milcon LS (trade name), SS, E, LS-2, SS-2, and MS-2, as well as Fineflex (registered trademark) manufactured by NICHIAS Corporation. , Ruber (registered trademark), Denka Arsene (trade name) manufactured by Denki Kagaku Kogyo Co., Ltd., Isowool (registered trademark) 1400, 1500, 1600, etc. of Isolite Industry. In general, inorganic fibers having an average fiber length of 30 μm or less are short fibers, but those having an average fiber length of less than 1 mm may be used as the short fibers.

  The inorganic fine powder prevents the inorganic long fiber from being broken or broken by filling the gap between the high heat resistant inorganic long fiber and the high heat resistant inorganic short fiber and dispersing the load applied to the inorganic long fiber. Added for the purpose, having a melting point equal to or higher than the maximum use temperature of inorganic long fibers and inorganic short fibers, and having an average particle size approximately equal to or smaller than the diameter of the inorganic long fibers, specifically Any melting point can be used as long as it has a melting point of 1300 ° C. or higher, preferably 1400 ° C. or higher and an average particle size of 0.1 to 10 μm, preferably 0.2 to 6 μm. Specifically, the inorganic fine powder includes, for example, rock fine powder such as clay and talc, oxide fine powder such as alumina, titanium oxide, silica, mullite, cordierite, ferrite and magnesium oxide; silicon nitride, nitriding Fine nitride powders such as aluminum and boron nitride; fine carbide powders such as silicon carbide, titanium carbide and tungsten carbide can be used. Among the commercial products, Hayashi Kasei Co., Ltd. micelleton (trade name), micron white (trade name) 5000S, 5000P, 5000SD, 5000A, 5000B, Showa Mining Co., Ltd. Mircon MS (trade name), Kyocera Corporation Fine talc such as silicon nitride SN281 (trade name), Mircon (trade name) LS, SS, manufactured by Hayashi Kasei Co., Ltd., silicon nitride KSN-10SU, KSN-10SP, KSN-10M, manufactured by Shin-Etsu Chemical Co., Ltd. TX, KSN-10L, Showa Denko Co., Ltd. Boron Nitride powder Sho BN (registered trademark) UHP, Ruby En (registered trademark) LBN, Sumitomo Chemical Co., Ltd. high purity alumina AKP-20, AKP-30, AKP- 50, activated alumina KHA-46, KHA-24, KHO-46, KHO-24, K D-46, KHD-24, NKHD-46, NKHD-24, etc., silicon nitride powder HM-5 manufactured by Chichibu Onoda Co., Ltd., HM-5MF, boron nitride powder GP manufactured by Denki Kagaku Kogyo Co., Ltd., Examples thereof include SP-1 and SP-2, Boron carbide (trade name: Denkaboron powder) manufactured by Denki Kagaku Kogyo Co., Ltd., silicon nitride manufactured by the same company, aluminum nitride powder manufactured by Tokuyama Corporation.

As the heat-resistant and corrosion-resistant alloy, stainless steel containing Cr 15-30%, Ni 10-80%, C 0.4% or less, or nickel-based heat-resistant alloy containing Cr 15-30% and Ni 10-80%, these heat resistant corrosion resistant alloys are preferable. In this case, a sheet having a thickness of 0.1 to 1.0 mm may be used. Specifically, the stainless steel is C0.4% or less, preferably 0.1% or less, and may contain one or more of Ti, Nb, Mo, Cu and Si. Steel is preferred, and commercially available products include SUS310, SUS309S, SUS321, SUS347, and Incoloy (registered trademark) 800.
In addition, the nickel-base heat-resistant alloy is preferably a nickel alloy containing Ni 40 to 80% and Cr 15 to 30%. Commercially available nickel-base heat-resistant alloys such as Inconel (registered trademark) 600, 601, 625, and 718 Is mentioned.

  The high heat-resistant gasket according to the present invention can be manufactured as follows. In the present invention, when an inorganic fiber sheet made of an inorganic material is manufactured, the high heat-resistant inorganic short fibers 10 to 60% and the high heat-resistant inorganic short fibers 10 are used in order to increase the strength in the manufacturing process and improve the handleability. In addition to -20% and inorganic fine powder 15-60%, organic fiber 2-10% and binder 5% or less are blended and dispersed in water. Is dried and further cut into a predetermined shape to prepare a raw sheet for internal material.

  On the other hand, a metal sheet for a jacket made of a heat-resistant and corrosion-resistant alloy (high chromium high nickel low carbon stainless steel or nickel base heat resistant alloy) is determined by a die, a Thomson die, a circular cutter, a laser, an electron beam, a jet water flow, or other means. This is cut into a shape and pressed with a die or a simple die to form a U-shaped or U-shaped jacket body member and an I-shaped jacket lid member. Next, after the raw sheet is disposed in the recess of the jacket body member, a jacket lid member is placed, and the inner edge and the outer edge of the jacket body member are crimped to obtain a metal jacket type raw gasket. This raw gasket can be used as it is.

  In addition, as said organic fiber, polyparaphenylene benzoxador (PBO) fiber, aramid fiber, nylon fiber, acrylic fiber and other artificial fibers, pulp, manila hemp and other natural fibers can be used.

  As the binder, either an organic binder or an inorganic binder may be used, and the organic binder includes a natural binder and a synthetic binder typified by starch paste. As the inorganic binder, a heat-resistant inorganic adhesive mainly composed of alumina or silica can be used, and commercially available products include hydraulic alumina BK-112 and BK-103 manufactured by Sumitomo Chemical Co., Ltd., TA Chemical Co., Ltd. Company-made Betac # 1300, # 1550B, Showa Mining Co., Ltd., Milcon SP, LS, Asahi Chemical Industry Co., Ltd., Sumiceram S, and the like.

  In an embodiment in which the raw gasket is used as it is, the raw gasket is heated to a high temperature in a trial operation or an initial stage of operation after being attached to equipment or a machine, and an organic fiber or an organic binder used as an internal material of the gasket in the process. Pyrolysis results in an inorganic fiber sheet having a composition that does not contain organic matter, but it is necessary to perform bolting in anticipation of weight loss due to the organic matter.

Therefore, according to the present invention, it is a metal jacket type gasket formed by coating an inorganic fiber sheet made of an inorganic material with a metal jacket, and the inorganic fiber sheet has a high heat-resistant inorganic fiber having a maximum use temperature of 1250 ° C. or more. 10 to 60%, high heat-resistant inorganic short fibers 10 to 20% whose maximum use temperature is 1250 ° C. or higher, inorganic fine powder 15 to 60% having a melting point higher than the maximum use temperature of the high heat-resistant inorganic fibers, organic is formed with a mixture consisting of 2-10% fiber and 5% binder, high heat gasket is obtained in which the metal jacket is characterized by comprising the heat-resistant corrosion-resistant alloy.

  Normally, after the raw gasket is manufactured, the thickness of the gasket is adjusted by thermally decomposing the organic matter by heat treatment at a temperature in the range of 400 to 550 ° C. where the organic fibers and the organic binder disappear, and then performing a finishing press. Product.

  Moreover, when manufacturing the gasket which has a bolt hole, the said raw gasket is punched with a Thomson type | mold etc., a bolt hole is drilled, and the said heat processing and finishing press should just be performed after that. If necessary, the grommet may be fitted into the bolt hole after heat treating the raw gasket. In addition, when a certain pressure is applied to the gasket and the gasket is left in that state for a predetermined time, for example, 10 hours or more, the sealing performance can be improved.

  According to the present invention, (i) the inorganic fine powder is added to the inorganic fiber as the material of the inorganic fiber sheet, and the amount of the alumina silica fiber is 60% or less. (B) Since it is a metal jacket type gasket that can prevent the wear of Thomson blade, it can be manufactured easily even if there is a lot of powder. (C) When manufacturing internal materials, organic fibers and binder are added. Since the strength is increased by mixing, handling in the manufacturing process is easy. (D) After the gasket is completed, the organic matter of the organic fiber and binder disappears, and the elasticity of the fine powder is obtained by adding inorganic fine powder. Can be maintained at a high temperature, eliminating uneven density of the sheet, homogenizing the sheet, and increasing the surface pressure of the gasket. (E) Metal jacket Since a high chromium high nickel low carbon stainless steel plate or heat resistant nickel base alloy plate excellent in corrosion resistance is adopted as a material, no pitting corrosion occurs even at 700 to 750 ° C., and it can be used even at a high temperature of 900 ° C. or higher. (F) Since the gasket can be used at a high temperature of 900 ° C. or higher, the equipment can be operated at a high temperature, energy can be used efficiently, and at the same time, the generation of dioxins and the like can be prevented and environmental pollution can be suppressed. ) Even when discarded after using the gasket, since the gasket is composed only of a metal and an inorganic material, it is possible to obtain an excellent effect such that the gasket can be disassembled and separated and collected.

  As shown in FIG. 1, a metal jacket type high heat resistant gasket 1 according to the present invention is encased in a metal jacket composed of a U-shaped metal jacket body member 2 and an I-shaped metal jacket lid member 3, and the inside thereof. The high heat resistant gasket 1 has a bolt hole 4 formed through the metal jacket lid member 3, the inorganic fiber sheet 5 and the metal jacket main body member 2.

  The metal jacket type high heat resistant gasket 1 is manufactured as follows. First, Isowool (registered trademark) 1400 of Isolite Industry Co., Ltd. is used as an inorganic long fiber having a maximum use temperature of 1300 ° C. or more, and Mircon SL manufactured by Hayashi Kasei Co., Ltd. as an inorganic short fiber having a maximum use temperature of 1300 ° C. or more. (Fiber length: 50μ, fiber diameter: 0.2μ), talc is used as inorganic fine powder, and these are blended together with organic fibers (pulp) and binder (starch glue) in the weight percentage shown in Table 1, A papermaking liquid is obtained by dispersing in water.

  The papermaking liquid is made with a papermaking machine to form a sheet having a thickness of 2 mm, and this sheet is punched into a predetermined shape with a Thomson mold to obtain a raw sheet of raw inorganic fibers.

  Separately from this, 0.25 mm thick SUS310 (Cr 25%, Ni 20.5%, C 0.08% or less, Mn 2.0% or less) is die-cut to obtain a U-shaped metal jacket main body member 2 and a section I. After forming the letter-shaped metal jacket lid member 3 and placing the inorganic fiber sheet 5 in the U-shaped metal jacket main body member 2, the I-shaped metal jacket lid member 3 is placed thereon, A metal jacket type raw gasket is obtained by caulking and integrating the inner edge 2a and outer edge 2b of the letter-shaped metal jacket body member 2. Next, as shown in FIG. 1 (b), after the bolt hole 4 was drilled in the raw gasket, this was heat-treated at 500 ° C. to decompose and remove the organic matter to produce the inorganic fiber sheet 5, and then finish. The gasket thickness is adjusted to 2.3-2.5 mm by pressing to obtain a metal jacket type gasket 1.

  Note that it is not always necessary to make a bolt hole in the raw gasket, and the grommet 6 may be attached to the bolt hole formed in the gasket 1 (see FIG. 1C).

The figure which shows the manufacture process of the metal jacket type gasket which concerns on this invention

Explanation of symbols

1: Metal jacket type gasket 2: Metal jacket body member 3: Metal jacket lid member 4: Bolt hole 5: Inorganic fiber sheet

Claims (6)

10 to 60% highly heat resistant inorganic long fibers having a fiber length of 2 to 40 mm, 5 to 20% highly heat resistant inorganic short fibers having a fiber length of less than 1 mm, and inorganic fine fibers having an average particle diameter of 0.1 to 10 μm include powders 3 0-8 0%, the inorganic fiber sheet sum of the high heat-resistant inorganic long fibers and high heat resistant inorganic short fibers made of the composition is 20 to 70%, a metal jacket made of heat corrosion resistant alloy Metal jacket type high heat resistant gasket. The high heat resistant gasket according to claim 1, wherein the heat resistant inorganic short fiber is sepiolite.   2. The high heat resistant gasket according to claim 1, wherein the heat resistant and corrosion resistant alloy is a high chromium high nickel low carbon stainless steel containing 15 to 30% Cr, 10 to 80% Ni, and C 0.4% or less.   The high heat-resistant gasket according to claim 1, wherein the heat-resistant and corrosion-resistant alloy is a nickel-based heat-resistant alloy containing 15 to 30% Cr and 10 to 80% Ni. 10 to 50% high heat resistant inorganic long fibers having a fiber length of 2 to 40 mm, 10 to 20% high heat resistant inorganic short fibers having a fiber length of less than 1 mm, and inorganic fine fibers having an average particle diameter of 0.1 to 10 μm Blend 30% to 60% powder, 2% to 10% organic fiber, and 5% or less of binder, create a sheet, cut the sheet into a predetermined shape, and place it in a U-shaped cross-section metal jacket member. In addition, a metal jacket member having an I-shaped cross section is disposed thereon, integrated by caulking, heat-treated at a predetermined temperature to decompose and dissipate the organic matter and the binder, and then finish press. Manufacturing method of gasket. 10 to 50% high heat resistant inorganic long fibers having a fiber length of 2 to 40 mm, 10 to 20% high heat resistant inorganic short fibers having a fiber length of less than 1 mm, and inorganic fine fibers having an average particle diameter of 0.1 to 10 μm Blend 30% to 60% powder, 2% to 10% organic fiber, and 5% or less of binder, create a sheet, cut the sheet into a predetermined shape, and place it in a U-shaped cross-section metal jacket member. A method for producing a high heat-resistant gasket, characterized in that an I-shaped cross-sectional metal jacket member is disposed thereon, integrated by caulking, and then finish-pressed.

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