JPH0562674B2 - - Google Patents

Description

[Detailed description of the invention]

a. Purpose of the Invention (Field of Industrial Application) The gasket according to the present invention is a cylinder head gasket for maintaining airtightness and liquidtightness between the upper surface of the cylinder block and the lower surface of the cylinder head of an engine, or an exhaust pipe joint. It can be used as a gasket to keep the area airtight. (Prior Art) Gaskets used in parts exposed to high temperatures, such as cylinder head gaskets or exhaust pipe joint gaskets, have conventionally been made using asbestos. However, in recent years, it has become known that inhaling the fibers of asbestos can lead to an extremely high incidence of lung cancer, and the use of asbestos has been discouraged in various industrial fields. Research has been conducted on gasket materials that do not contain
Various gaskets have been proposed and are actually used. (Problems to be Solved by the Invention) However, the gaskets that have been proposed and are currently in use do not necessarily have sufficient sealing performance compared to gaskets using asbestos. An object of the present invention is to provide a gasket that does not use asbestos, but can exhibit the same sealing performance as a gasket that uses asbestos. b. Structure of the invention (means for solving the problem) The gasket of the present invention contains one or more fibrous substances other than asbestos, natural rubber, styrene-butadiene rubber, and acrylonitrile as a filler as a main component. butadiene rubber, acrylic rubber,
A composition obtained by mixing one or more of silicone rubber and fluororubber is provided on both sides of a plate-shaped metal core material. Fillers include one or more of talc, clay, barium sulfate, silica, mica, carbon, etc., and fibrous substances other than asbestos include:
Aromatic polyamide fiber, phenolic resin fiber, aromatic polyester fiber, aromatic polyimide fiber,
One or more of aromatic polybenzimidazole fibers, rock wool, alumina-silicate fibers, glass fibers, phosphate fibers, carbon fibers, sepiolite, etc. are used. Furthermore, in the gasket of the present invention, the density of the composition provided on both sides of the metal core material is 1.80 g/cm ³
That's all. In addition, as a method for providing the desired composition on both sides of the metal core material, it is preferable to directly laminate the composition on both sides of the metal core material by a roll method. Alternatively, it can be made by making a beater sheet using a paper machine and attaching this to both sides of a metal core material. (Function) The gasket of the present invention configured as described above has the following features:
As with conventional gaskets, it is used between the top surface of the cylinder block and the bottom surface of the cylinder head, or between the exhaust pipe joint, but because the density of the gasket material is 1.80 g/cm ³ or higher, The sealing properties of the gasket material are improved, and the airtightness of the part where the gasket is installed can be reliably maintained. (Example) Next, an example of the present invention will be described. Example 1 As a rubber material, Nitzpol LX513, which is acrylonitrile butadiene rubber manufactured by Nippon Zeon Co., Ltd.
100 parts of (product name) (all mixing ratios are parts by weight)
It is expressed as )added. As a fibrous substance, 200 parts of Ibiwool (trade name), a ceramic fiber manufactured by Ibikawa Electric Co., Ltd.
A mixture of 40 parts of Kevlar 29 (trade name) manufactured by DuPont was added. As a filler, 350 parts of Soft Crane Neocaria K (trade name) manufactured by Asada Seifun Co., Ltd. and 350 parts of Talc SW (trade name) manufactured by Nippon Talc Co., Ltd. were mixed and added. To the above materials, a mixture of 5 parts of sulfur manufactured by Hosoi Chemical Co., Ltd. as a vulcanizing agent and 5 parts of Noxeler TT (trade name) manufactured by Ouchi Shinko Chemical Co., Ltd. as a vulcanization accelerator was added. . All of these materials were put into a kneading machine and kneaded uniformly to produce a gasket compound containing no asbestos. This compound is uniformly imprinted on both sides of a metal core material (iron plate with hooks), which is made by folding a large number of hooks on the front and back sides of a galvanized steel plate with a thickness of 0.20 mm, using a calendar roll method, and then vulcanized to form the entire surface. The thickness of the compound is 1.2mm and the density of the compound is 1.92.
A gasket of g/cm ³ was obtained. In order to measure the sealing performance of this gasket, one gasket with a hole for fluid passage formed in the center was used.
A seal performance test was conducted in which the pressure of water and engine oil existing inside the hole was increased by 1 kg/ ^cm2 by holding the flanges between the pair of flanges, and the results shown in Table 1 were obtained. It was done. That is, when the pressure for tightening the gasket between a pair of flanges was 50 kg/cm ² , leakage occurred when the pressure of the water inside the hole reached 8.0 kg/cm ² . Furthermore, when the pressure for tightening the gasket between a pair of flanges was 100 kg/cm ² , leakage occurred when the pressure of the water existing inside the hole reached 12.0 kg/cm ² . Furthermore, if the fluid existing inside the hole is engine oil, the tightening pressure is 50Kg/cm ² , the engine oil pressure is 15.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 25.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of gaskets using asbestos, which are listed as Comparative Examples 4 and 5 in Table 2, and is sufficient for practical use. In addition, the gaskets of Comparative Examples 4 and 5 are as follows:
All points other than the materials and density listed in Table 2 were made in the same manner as in the examples of the present invention, and the sealing properties were tested in the same manner. Example 2 As a rubber material, Nitzpol LX513, which is acrylonitrile butadiene rubber manufactured by Nippon Zeon Co., Ltd.
100 parts of (trade name), CMF (trade name), which is a ceramic fiber manufactured by Nippon Cement Co., Ltd., as a fibrous material.
and 200 copies of Kynol (product name) manufactured by Gunei Chemical Co., Ltd.
All Examples except that 40 parts of , 350 parts of Translink 37 (trade name) manufactured by Engelhard Co., Ltd. and 300 parts of Mistron Vapor Talc (trade name) manufactured by Nippon Mistron Kogyo Co., Ltd. were used as fillers. Using the same materials and method as 1, the density of the compound was 1.90g/
A gasket of cm ³ was obtained. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 8.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
In the case of Kg/ ^cm2 , leakage occurred when the water pressure reached 12.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 14.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 25.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 3 As a fibrous substance, 250 parts of Innofil (trade name), a ceramic fiber manufactured by Laxoburg, were used.
As a filler, 350 parts of Sototokle Neocaria K (trade name) manufactured by Asada Seifun Co., Ltd. and Mistron Vapor Talc (trade name) manufactured by Nihon Mistron Kogyo Co., Ltd.
All the same materials as in Example 1 except that 300 parts of
Depending on the method, the combined density is 1.88g/ ^cm3
I got a gust. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 8.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 11.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 14.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 25.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 4 100 parts of Perbunan 3810 (trade name), an acrylonitrile butadiene rubber manufactured by Bayer, was used as the rubber material, and 300 parts of Talc SW (trade name) manufactured by Nippon Talc Co., Ltd., used as a filler, were used. Using all the same materials and methods as in Example 1, a gust having a compound density of 1.85 g/cm ³ was obtained. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 7.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 10.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 14.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 5 As a rubber material, Perbunan 3810 (trade name), an acrylonitrile butaene rubber manufactured by Bayer, was used.
All the same materials as in Example 2 except that 100 parts of
Depending on the method, the density of the compound is 1.90g/cm ³
I got a gust. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 8.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
In the case of Kg/ ^cm2 , leakage occurred when the water pressure reached 12.0Kg/ ^cm2 , respectively. Furthermore, if the fluid existing inside the hole is engine oil, the tightening pressure is 50Kg/cm ² , the engine oil pressure is 15.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 6 All the materials and methods were the same as in Example 3, except that 100 parts of Perbunan 3810 (trade name), an acrylonitrile butadiene rubber manufactured by Bayer, was used as the rubber material, and the density of the compound was 1.83.
A gasket of g/cm ³ was obtained. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 7.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 10.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 13.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 7 As a rubber material, 100 parts of Nitzpol AR-51 (trade name), an acrylic rubber manufactured by Zeon Corporation, were used.
As a vulcanizing agent, Barnotsuk manufactured by Ouchi Shinko Kagaku Co., Ltd.
The density of the compound was 1.83 using the same materials and method as in Example 1 except that 4 parts of AB (trade name) was used.
A gasket of g/cm ³ was obtained. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 7.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 10.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 13.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 8 As a rubber material, 100 parts of Nitzpol AR-51 (trade name), an acrylic rubber manufactured by Zeon Corporation, were used.
350 parts of Mistron vapor talc (trade name) manufactured by Nihon Mistron Kogyo Co., Ltd. used as a filler,
As a vulcanizing agent, Barnotsuk manufactured by Ouchi Shinko Kagaku Co., Ltd.
The density of the compound was changed using the same materials and method as in Example 2 except that 4 parts of AB (trade name) was used.
A gasket of 1.85 g/cm ³ was obtained. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 7.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 10.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 13.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 9 As a rubber material, 100 parts of Nitzpol AR-51 (trade name), an acrylic rubber manufactured by Zeon Corporation, were used.
As a vulcanizing agent, Barnotsuk manufactured by Ouchi Shinko Kagaku Co., Ltd.
The density of the compound was made using the same materials and method as in Example 3 except that 4 parts of AB (trade name) was used.
A gasket of 1.91 g/cm ³ was obtained. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 8.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 11.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 14.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 25.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 10 As a rubber material, 100 parts of Nitzpol AR-51 (trade name), an acrylic rubber manufactured by Nippon Zeon Co., Ltd.
As a fibrous substance, 200 parts of Innofil (trade name), a ceramic fiber manufactured by Laxoburg,
40 parts of Kynol (trade name) manufactured by Gunei Chemical Co., Ltd. as a filler, 350 parts of Translink 37 (trade name) manufactured by Engelhard, and Mistron vapor talc (trade name) manufactured by Nihon Mistron Kogyo Co., Ltd. 300
The density of the compound was 1.82 g /
A gasket of cm ³ was obtained. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 7.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 10.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 13.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 11 As a rubber material, 100% of Noxtite A1095 (trade name), an acrylic rubber manufactured by Nippon Mectro Co., Ltd.
Same as Example 1, except that 3 parts of sulfur manufactured by Hosoi Chemical Co., Ltd. was used as a vulcanizing agent, and 5 parts of Noxeler H (trade name) manufactured by Ouchi Shinko Chemical Co., Ltd. was used as a vulcanization accelerator. Depending on the material and method, a gust with a compound density of 1.85 g/cm ³ was obtained. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 7.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 10.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 13.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 25.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 12 As a rubber material, Noxtite A1095 (trade name), an acrylic rubber manufactured by Nippon Mectron Co., Ltd., was used.
100 parts, 3 parts of sulfur manufactured by Hosoi Chemical Co., Ltd. as a vulcanizing agent.
A compound with a density of 1.85 g/cm ³ was prepared using the same materials and method as in Example 2, except that 5 parts of Noxela H (trade name) manufactured by Ouchi Shinko Kagaku Co., Ltd. was used as a vulcanization accelerator. I got a gust. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 8.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 11.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 14.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 13 As a rubber material, Noxtite A1095 (trade name), an acrylic rubber manufactured by Nippon Mectron Co., Ltd., was used.
100 parts, 3 parts of sulfur manufactured by Hosoi Chemical Co., Ltd. as a vulcanizing agent.
The density of the compound was 1.84 g/cm ³ using the same materials and method as in Example 3, except that 5 parts of Noxeler H (trade name) manufactured by Ouchi Shinko Kagaku Co., Ltd. was used as a vulcanization accelerator. I got a gasket. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 7.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 10.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 13.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Example 14 The same materials as in Example 12 were used, except that 200 parts of Innofil (trade name), a ceramic fiber manufactured by Laxoburg, and 40 parts of Kevlar 29 (trade name), manufactured by Dapon, were used as the fibrous substances. A gasket with a compound density of 1.82 g/cm ³ was obtained by this method. The sealing performance of this gasket was measured using the same test method as in Example 1, and the results are shown in Table 1. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 7.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/ ^cm2 , leakage occurred when the water pressure reached 10.0Kg/ ^cm2 , respectively. Furthermore, assuming that the fluid existing inside the hole is engine oil, when the tightening pressure is 50Kg/cm ² , the engine oil pressure is 13.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 24.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is comparable to the sealing performance of a gasket using asbestos, and is sufficient for practical use. Next, an experiment conducted on a comparative example will be explained in order to confirm the effects of the present invention. Comparison row 1 As shown in Table 2, the compound had exactly the same composition as Example 1, and only the density of the compound was 1.70 g/cm ³
When the sealing performance of the gasket was measured at a value lower than the range of the present invention, the results shown in Table 2 were obtained. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 2.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/cm ² , when the water pressure reaches 4.0Kg/cm ² ,
A leak occurred in each case. Furthermore, if the fluid existing inside the hole is engine oil, the tightening pressure is 50Kg/cm ² , the engine oil pressure is 5.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 10.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is considerably inferior to the sealing performance of the gasket according to the present invention, and is insufficient for practical use. Comparative Example 2 As shown in Table 2, the compound had exactly the same composition as Example 5, and only the density of the compound was 1.65 g/cm ³
When the sealing performance of the gasket was measured at a value lower than the range of the present invention, the results shown in Table 2 were obtained. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 2.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/cm ² , when the water pressure reaches 3.0Kg/cm ² ,
A leak occurred in each case. Furthermore, if the fluid existing inside the hole is engine oil, the tightening pressure is 50Kg/cm ² , the engine oil pressure is 4.0Kg/cm ² , and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 10.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is considerably inferior to the sealing performance of the gasket according to the present invention, and is insufficient for practical use. Comparative Example 3 As shown in Table 2, it had exactly the same composition as Example 7, and only the density of the compound was 1.74 g/cm ³
When the sealing performance of the gasket was measured at a value lower than the range of the present invention, the results shown in Table 2 were obtained. In other words, assuming that the fluid existing inside the pore is water,
When the tightening pressure of the flange is 50Kg/ ^cm2 , the pressure of water inside the hole is 2.0Kg/ ^cm2 , and the tightening pressure is 100Kg/cm2.
Kg/cm ² , when the water pressure reaches 4.0Kg/cm ² ,
A leak occurred in each case. Furthermore, if the fluid existing inside the hole is engine oil, the tightening pressure is 50Kg/cm ² , the engine oil pressure is 5.0Kg/cm ² and the tightening pressure is 100Kg/cm 2 .
Kg/cm ² , engine oil pressure is 10.0
When reaching Kg/ ^cm2 , leakage occurred respectively. This value is considerably inferior to the sealing performance of the gasket according to the present invention, and is insufficient for practical use. c. Effects of the Invention As stated above, the gasket of the present invention can obtain sufficient sealing performance without using asbestos, which has a strong possibility of causing harm to the human body.
Great industrial effect.

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Claims (1)

[Claims] 1 The filler, which is the main component, contains 1 other than asbestos.
A composition in which a seed or two or more fibrous substances are mixed with one or more of natural rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, acrylic rubber, silicone rubber, and fluororubber is mixed into a plate-shaped metal core. A gasket provided on both sides of a metal core material, where the density of the composition provided on both sides of the metal core material is
A gasket with a weight of 1.80 g/cm ³ or more.