WO2019053760A1

WO2019053760A1 - Gasket including talc sheet

Info

Publication number: WO2019053760A1
Application number: PCT/JP2017/032739
Authority: WO
Inventors: 聡美高橋
Original assignee: 株式会社バルカー
Priority date: 2017-09-12
Filing date: 2017-09-12
Publication date: 2019-03-21
Also published as: CN111094812A; KR20200014923A; KR102354535B1; SG11201913095WA

Abstract

Provided is a gasket including a talc sheet containing: talc; an inorganic fiber; and a binder, wherein the ten-point average roughness (Rz) of both surfaces of the talc sheet is 20 μm or less as measured according to JIS B 0031(1994).

Description

Gasket including talc sheet

The present invention relates to a gasket including a talc sheet, which is used for fluid piping connection and the like.

Generally, three main types of gaskets are non-metallic gaskets, semi-metallic gaskets and metal jacket gaskets. Among the nonmetallic gaskets, sheet gaskets containing inorganic fillers and inorganic fibers having high heat resistance and woven gaskets obtained by rubberizing inorganic fibers are generally used under high temperature conditions of 450 ° C. or higher.

Patent Document 1 discloses a seal material containing an inorganic fiber, an inorganic filler and a binder as a seal material of a non-metallic gasket.

JP-A-59-86683

However, when using a gasket containing a seal material containing an inorganic fiber, an inorganic filler and a binder, the fluid in the piping leaks to the outside along the gasket surface, so-called surface leakage between the gasket and the flange It became clear that there was a room for improvement in sealability.

An object of the present invention is to provide a gasket having an improved sealability.

The present invention provides a gasket comprising a talc sheet shown below.
[1] A gasket comprising a talc sheet containing talc, inorganic fibers and a binder, wherein a ten-point average roughness (R _Z ) according to JIS B 0031 (1994) on both surfaces of the talc sheet is 20 μm or less gasket.

[2] The gasket according to [1], wherein the inorganic fiber is at least one fiber selected from the group consisting of alumina fiber, glass fiber, rock wool, basart fiber, bio-soluble fiber, silica fiber and ceramic fiber. .

[3] The gasket according to [1] or [2], wherein the inorganic fiber is an alumina fiber or a basalt fiber.

[4] The gasket according to any one of [1] to [3], wherein the heat loss ratio at 800 ° C. according to JIS K 7120 of the talc sheet is 15% by weight or less.

[5] The gasket according to any one of [1] to [4], wherein the particle diameter of the talc is 2 μm to 25 μm.

[6] The laminate includes two or more talc sheets, the laminate includes a metal plate, the material of the metal plate is a stainless steel material or a carbon steel material, and the shape of the metal plate is a flat metal, a wire mesh, The gasket according to any one of [1] to [5], which is at least one shape selected from the group consisting of a hook metal and an expanded metal.

[7] The gasket according to any one of [1] to [6], which is at least one gasket selected from the group consisting of a spiral wound gasket, a semimetal gasket, and a metal jacket gasket.

The gasket containing a talc sheet according to the present invention has an R _Z of 20 μm or less on both sides of the talc sheet. Therefore, a sufficient fit can be obtained between the gasket and the flange, and the contact surface leakage between the gasket and the flange can be improved.

Hereinafter, the gasket containing the talc sheet of the present invention will be described in more detail.
[Average aspect ratio of talc]
The average aspect ratio of talc used in the present invention is preferably 10 to 25. The average aspect ratio of talc referred to herein is the ratio of the average diameter to the average thickness of talc particles, and can be calculated from (average diameter / average thickness). If the average aspect ratio of talc is less than 10, there is a risk that talc sheet both sides of R _Z is greater than 20 [mu] m. The upper limit value of the average aspect ratio of talc is not particularly limited, but usually, the average aspect ratio of talc is 25 or less. The specific measuring method of the average aspect ratio of talc follows the description of the item of the Example mentioned later.

[Average particle size of talc]
The average particle diameter of talc used in the present invention is preferably 2 μm or more and 25 μm or less. If the average particle size of talc is less than 2 μm, formation of a talc sheet tends to be difficult. When the average particle diameter of the talc exceeds 25μm, there is a possibility that talc sheet both sides of R _Z is greater than 20 [mu] m. The measurement of the average particle diameter of talc is a value measured using a laser diffraction particle size distribution measuring device. The specific measuring method of average particle diameter follows the description of the term of the Example mentioned later.

[Inorganic fiber]
The inorganic fibers used in the present invention play a role of enhancing the mechanical strength of the talc sheet. As such an inorganic fiber, for example, alumina fiber, glass fiber, rock wool, basalt fiber, biosoluble fiber, silica fiber and ceramic fiber are preferable. It is further preferable to use alumina fiber to improve heat resistance and basart fiber to improve mechanical strength.

[Average fiber diameter of inorganic fibers]
The average fiber diameter of the inorganic fibers used in the present invention is preferably in the range of 3 to 20 μm. When the average fiber diameter of the inorganic fibers is greater than 20 [mu] m, there is a risk that talc sheet both sides of R _Z is greater than 20 [mu] m. If the average fiber diameter of the inorganic fibers is less than 3 μm, the mechanical strength of the talc sheet tends to decrease. The specific measuring method of the average fiber diameter of inorganic fiber follows the description of the term of the Example mentioned later.

[binder]
The binder used in the present invention may be of any type as long as it can bond talc and inorganic fibers to enhance sealing performance and impart mechanical strength to the talc sheet. An organic binder, for example, can be used to suitably bond talc and inorganic fibers in the talc sheet. Examples of the organic binder include acrylonitrile butadiene rubber, natural rubber, isoprene rubber, chloroprene rubber, acrylonitrile rubber, styrene-butadiene rubber, butyl rubber, fluororubber, silicone rubber, ethylene-propylene rubber and the like. These binders may be used alone or in combination of two or more.

[10-point average roughness (R _Z )]
In the present invention, the ten-point average roughness (R _Z ) according to JIS B 0031 (1994) on both sides of the talc sheet is 20 μm or less. R _Z can be measured as follows. First, only the evaluation length (8 mm) is extracted from the roughness phase in the direction of the mean line. Then, the average value of the absolute values of the highest peaks from the highest peak to the fifth peak measured in the direction of the longitudinal magnification from the average line of this extraction portion and the absolute value of the heights of the lowest valley bottoms to the fifth valley bottom Find the sum of R _Z is the value expressed in micrometers (μm). The specific measuring method of R _Z follows the description of the item of the Example mentioned later.

Heat loss rate
It is preferable that the heat loss ratio at 800 ° C. of the talc sheet used in the present invention in accordance with JIS K 7120 (a method for measuring the thermal weight of plastic) is 15% or less. When the heat loss ratio at 800 ° C. of the talc sheet exceeds 15%, the sealability at high temperature tends to be lowered. The specific measurement method of the heat loss ratio follows the description of the section of the example described later.

The talc sheet used in the present invention may contain, in addition to the components as described above, various vulcanizing agents, vulcanization accelerators, vulcanization assistants, colorants and the like, as necessary.

[gasket]
A gasket according to the present invention includes the above-mentioned talc sheet. The gasket according to the present invention can be easily manufactured, for example, by cutting out the talc sheet into a desired shape. The gasket according to the present invention may include two or more talc sheets. It is also possible to include two or more talc sheets and a reinforcing material such as a thin metal plate, a wire mesh, a hook metal or the like for reinforcement. As a material of the said reinforcing material, stainless steel materials (SUS material) and carbon steel materials (SPCC materials) can be used.

The gasket including two or more talc sheets may be a laminate including two or more talc sheets having a structure in which the two or more talc sheets are sequentially laminated by pressure bonding. In addition, a laminate including two or more talc sheets may further include a reinforcing material, such as a structure in which a talc sheet, a reinforcing material, and a talc sheet are sequentially laminated.

The talc sheet can also be used as a filler material of a spiral gasket, a surface material of a semi-metal gasket, and a core material of a metal jacket gasket.

[Production method of talc sheet]
The talc sheet contained in the gasket which concerns on this invention can be manufactured using the dry method which is a manufacturing method of a common nonwoven fabric, a wet method, etc.

[Cylindrical gasket]
The gasket according to the present invention can be formed into a spiral gasket by using the above-mentioned talc sheet as a filler material. The spiral gasket is manufactured, for example, by using a single material or alloy such as stainless steel, carbon steel, inconel, hastelloy or the like as a hoop material, superposing the filler material and the hoop material, and winding in a spiral shape. can do.

[Semi-metal gasket]
The gasket according to the present invention can be made into a semi-metal gasket by using the above-mentioned talc sheet as a surface material. Semi-metal gaskets are manufactured, for example, by forming a layer of talc sheet as a surface material on both surfaces of stainless steel, carbon steel, single metal such as inconel, hastelloy, etc. Can.

[Metal jacket gasket]
The gasket according to the present invention can be made a metal jacket gasket by using the above-mentioned talc sheet as a core material. The metal jacket gasket can be manufactured, for example, by coating a thin film of a metal containing a single metal or alloy such as stainless steel, carbon steel, inconel, hastelloy or the like on the outside of a talc sheet as a core material.

Hereinafter, the gasket according to the present invention will be more specifically described with reference to examples, but the present invention is not limited by these examples.

Example 1
Containing 80 parts by weight of talc (Nippon Talc Co., Ltd .: MS-P (average particle diameter 15 μm, average aspect ratio 15)), 10 parts by weight of alumina fiber (average fiber diameter 5 to 10 μm) and 10 parts by weight of acrylonitrile butadiene rubber One talc sheet was produced by a wet method. And three sampled specimens from the talc sheets were evaluated for R _Z. In addition, three gaskets were produced from the talc sheet, and the sealability was evaluated. The heat loss ratio at 800 ° C. according to JIS K 7120 of the talc sheet was 12.5%.

Example 2
The inorganic fibers were prepared and evaluated under the same conditions as in Example 1 except that 7 parts by weight of alumina fibers (average fiber diameter 5 to 10 μm) and 3 parts by weight of basalt fibers (average fiber diameter 5 to 10 μm) were used. The heat loss ratio at 800 ° C. according to JIS K 7120 of the talc sheet was 13.0%.

Comparative Example 1
40 parts by weight of vermiculite (Vermitec Co., Ltd .: No. 0 (average particle size 0.7 mm)), talc (Nippon Talc Co., Ltd .: MS-P (average particle size 15 μm, average aspect ratio 15)) 40 One vermulite / talc sheet containing 10 parts by weight of rock wool (average fiber diameter: 5 to 10 μm) and 10 parts by weight of acrylonitrile butadiene rubber was prepared by a wet method. The vermiculite / talc and 3 taken specimens from the sheet, was evaluated for R _Z. In addition, three gaskets were produced from the vermiculite / talc sheet and evaluated for sealability. The heat loss ratio at 800 ° C. according to JIS K 7120 of the vermiculite / talc sheet was 13.5%.

[1] Conditions for Measuring Average Particle Size of Talc and Vermiculite The average particle size was measured using a laser diffraction particle size distribution measuring device (product name “SALD-2000J” manufactured by Shimadzu Corporation). As an average particle diameter, in the particle size distribution measured by the said apparatus, the value (median diameter) of the particle diameter when a cumulative number will be 50% was adopted.

[2] Measurement condition of average aspect ratio of talc The average aspect ratio is measured by observing at a magnification of 1000 using a scanning electron microscope (product name "S-3400N" manufactured by Hitachi High-Technologies Corporation). did. Specifically, the sample was fixed to a sample stage of a scanning electron microscope and photographed with a scanning electron microscope. Twenty particles were randomly selected from the photographed image, and the diameter and thickness of talc particles were measured, and then arithmetic averaging was performed. Thereby, the average diameter and the average thickness of the talc particles were calculated, and the ratio of the average diameter and the average thickness of the talc particles (average diameter of talc particles / average thickness) was determined, and it was defined as the average aspect ratio.

[3] Measurement Conditions of Average Fiber Diameter of Inorganic Fiber The average fiber diameter is observed by using a scanning electron microscope (product name “S-3400N” manufactured by Hitachi High-Technologies Corporation) at a magnification of 1000 times. It was measured. Specifically, the sample was fixed to a sample stage of a scanning electron microscope and photographed with a scanning electron microscope. Twenty particles were randomly selected from the photographed image, the fiber diameter was measured, and then arithmetic averaging was performed to obtain an average fiber diameter.

[4] Measurement Conditions of Heat Loss Rate Arbitrary sections of the talc sheet and the vermiculite / talc sheet were cut off to prepare a test piece, the mass of the test piece was measured, and the mass before heating was taken. The test piece is placed in an aluminum plate, and using a TG / DTA simultaneous measurement device (trade name: DTG-60, manufactured by Shimadzu Corporation) as a thermal analyzer, the temperature rising rate is 10 ° C./min under an air atmosphere. After heating from room temperature to 800 ° C. at an air flow rate of 150 ml / min, it was naturally cooled to room temperature. The mass was measured again to obtain the mass after heating. The heat loss ratio was calculated by the following equation (1) using the obtained mass before heating and the mass after heating.
(1) Heat loss ratio (%) = (mass before heating−mass after heating) / mass before heating × 100
[5] Verification Experiment Conditions sheets both sides of _{R Z} of evaluation of the sheet surfaces of _{R Z} uses Tokyo Seimitsu Co. Surfcom 480A, was measured in a manner conforming to JIS B 0031 (1994). Measurements specimen 3 taken from the same talc sheet, and the same bar for Myu queue write three harvested specimens from sheets, the measurement of the sheet surfaces of R _Z were performed once each.

Evaluation length: 8.0 mm,
Evaluation speed: 0.3 mm / s,
Cutoff value: 0.8 mm.

(Evaluation standard of R _Z )
A: R _Z on both sides of the sheet is both 20 μm or less,
B: R _{Z on} both sides of the sheet is a value larger than 20 μm.

Verification test results of evaluation of R _{Z on} both sides of the sheet are shown in Table 1 below.

As shown in Table 1, the R _Z of all the sheet surfaces of the six test pieces collected from the talc sheet prepared in Examples 1 and 2 was 20 μm or less. Against it, R _Z of the seat surfaces of the three test pieces taken from the vermiculite / Talc sheet prepared in Comparative Example 1 were those exceeding all 20 [mu] m.

[6] Verification Experiment Condition of Sealability Evaluation Test gaskets 1 to 6 were attached to the flange portion installed in the compressed gas pipe, and a load was applied by a compression tester such that the surface pressure was 10 MPa. Helium gas with a temperature of 35 ° C. and a pressure of 0.2 MPa was supplied to the compressed gas piping, and helium leaking from the gasket was measured by a soap film flow meter.

(Evaluation standard of leakage)
A: The leakage amount of helium is less than 5.0 × 10 ^-2 (Pa · m ³ / s),
B: The leakage amount of helium is 5.0 × 10 ⁻² (Pa · m ³ / s) or more.

The results of the verification experiment are shown in Table 2 below.

As shown in Table 2, in the gaskets including the talc sheet produced in Examples 1 and 2, the leakage amount of helium is less than 5.0 × 10 ^-2 (Pa · m ³ / s) in all the produced 6 gaskets. there were. On the other hand, in the gasket containing vermiculite and talc sheet produced in Comparative Example 1, the leakage amount of helium in all three produced gaskets is 5.0 × 10 ⁻² (Pa · m ³ / s) or more Met. From these results, the both sides of R _Z is used gaskets comprising 20μm or less talc sheet, it has been shown that it is possible to improve the contact surface leakage between the gasket and the flange.

Claims

A gasket comprising a talc sheet containing talc, inorganic fibers and a binder, wherein
A gasket having a ten-point average roughness (R z ) according to JIS B 0031 (1994) on both sides of the talc sheet of 20 μm or less.
The gasket according to claim 1, wherein the inorganic fiber is at least one fiber selected from the group consisting of alumina fiber, glass fiber, rock wool, bascal fiber, biosoluble fiber, silica fiber and ceramic fiber.
The gasket according to claim 1, wherein the inorganic fiber is an alumina fiber or a basalt fiber.
The gasket according to any one of claims 1 to 3, wherein a heat loss ratio at 800 ° C according to JIS K 7120 of the talc sheet is 15% by weight or less.
The gasket according to any one of claims 1 to 4, wherein the particle size of the talc is 2 μm or more and 25 μm or less.
Including a laminate including two or more of the talc sheets,
The laminate includes a metal plate,
The material of the metal plate is stainless steel or cold rolled steel,
The gasket according to any one of claims 1 to 5, wherein the shape of the metal plate is at least one shape selected from the group consisting of flat metal, wire mesh, hook metal and expanded metal.
The gasket according to any one of claims 1 to 6, which is at least one gasket selected from the group consisting of a spiral gasket, a semimetal gasket, and a metal jacket gasket.