KR102149756B1 - Method for continuously Manufacturing a non-asbestos gasket - Google Patents

Abstract

The present invention relates to a continuous manufacturing method of a non-asbestos gasket, which manufactures a non-asbestos gasket having excellent heat resistance and pressure resistance performance by manufacturing a non-asbestos gasket sheet continuously cross-linked by not using an organic solvent but using a peroxidation cross-linking agent. The continuous manufacturing method of the non-asbestos gasket according to the present invention comprises: a raw material preparation step (S10); a kneader mixing step (S20); an open mill mixing step (S30); a sheet forming step (S40); a non-asbestos gasket sheet continuous manufacturing step (S50); a continuous cross-linking step (S60); and a non-asbestos gasket manufacturing step (S70).

Description

Method for continuously manufacturing a non-asbestos gasket}

The present invention relates to a method for continuously manufacturing a non-asbestos gasket, and more particularly, to a non-asbestos gasket sheet having excellent heat resistance and pressure resistance by manufacturing a non-asbestos gasket sheet that is continuously crosslinked using a peroxidation crosslinking agent without using an organic solvent. It relates to a continuous manufacturing method of a non-asbestos gasket.

In the conventional non-asbestos gasket composition, it is common to manufacture a gasket by kneading nitrile rubber swollen with an organic solvent, non-asbestos inorganic fiber, rubber additive, vulcanizing agent, and inorganic filler, and hot rolling it between a hot roll and a cooling roll.

Looking at a conventional patent for a non-asbestos gasket composition or manufacturing method, first, Japanese Laid-Open Patent No. 2008-0274053 describes a non-asbestos-based sheet gasket manufactured by agitating fibers, graphite, and rubber with water and stacking and integrating them according to a hot press. Published, and Japanese Laid-Open Patent No. 2005-0281463 relates to a joint sheet and manufacturing method using fibers other than asbestos. Fibers, rubber expanded with a solvent, rubber chemicals, activated clay, or acid clay are kneaded and then heated and rolled. It published about a method of manufacturing a joint sheet.

However, in the prior art, as a method for improving mechanical strength and heat resistance in manufacturing a non-asbestos gasket, it is common to use a rubber composition swollen in an organic solvent to mix an excessive amount of filler and fiber. However, the rubber composition swelled in the organic solvent causes a problem in that the mechanical strength and heat resistance are inferior. In addition, in the case of non-asbestos gaskets manufactured with organic solvents, manufacturing productivity and economics are very low, such as a manufacturing period of at least 2 to 3 days, leading to an increase in manufacturing cost and ultimately lowering price competitiveness. And other problems.

Japanese Patent Publication No. 2008-0274053 Japanese Patent Publication No. 2005-0281463

It is an object of the present invention to provide a continuous method for manufacturing a non-asbestos gasket that does not use an organic solvent, is harmless to the human body, and is more environmentally friendly.

In addition, an object of the present invention is to provide a method for continuously manufacturing a non-asbestos gasket having high tensile strength, elongation and modulus of elasticity.

In addition, it is an object of the present invention to provide a continuous manufacturing method of a non-asbestos gasket that continuously manufactures a non-asbestos sheet and improves production efficiency through a continuous crosslinking process.

The objects of the present invention are not limited to the above-mentioned objects, and other objects that are not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

In order to achieve the above object, the continuous manufacturing method of a non-asbestos gasket according to the present invention is a solid nitrile-butadiene rubber (NBR), a liquid nitrile-butadiene rubber (Nitrile-butadiene rubber, NBR), hydrogenated nitrile butadiene rubber ( Raw material preparation step (S10) of preparing a rubber raw material by weighing hydrogenated acrylonitrile butadiene rubber, HNBR); The rubber raw material prepared in the raw material preparation step and the inorganic blending agent, peroxidation crosslinking agent, pigment, anti-aging agent, plasticizer, flow enhancer, silane coupling agent, crosslinking donor, ozone inhibitor are added to a kneader and mixed. Kneader mixing step (S20); An open mill mixing step (S30) of mixing the mixture mixed in the kneader mixing step in an open mill; A sheet forming step (S40) of forming the mixture mixed in the open mill mixing step into a sheet and cooling it at room temperature; A non-asbestos gasket sheet continuous manufacturing step (S50) of extruding the sheet manufactured in the sheet forming step by using a sheet extruder to continuously extrude a sheet having a predetermined thickness and width (S50); A continuous crosslinking step (S60) of crosslinking the extruded sheet manufactured in the continuous manufacturing step of the non-asbestos gasket sheet using Rotocure; Non-asbestos gasket manufacturing step (S70) of cutting the sheet crosslinked in the continuous crosslinking step according to the standard of the gasket; Includes.

The rubber raw material prepared in the raw material preparation step (S10) includes 40 to 60 parts by weight of the solid nitrile-butadiene rubber (NBR), and liquid nitrile-butadiene rubber (Nitrile-butadiene) based on 100 parts by weight of the rubber raw material. rubber, NBR) 20 to 40 parts by weight and 15 to 25 parts by weight of hydrogenated nitrile butadiene rubber (HNBR).

At this time, the solid nitrile butadiene rubber in the raw material preparation step (S10) has an acrylonitrile content of 22 to 41 wt%, and the liquid nitrile butadiene rubber has an acrylonitrile content of 28 wt%. , The hydrogenated nitrile butadiene rubber is characterized in that the content of acrylonitrile is 33 to 42% by weight.

The kneader mixing step (S20) includes a first kneader mixing step (S21) of mixing the raw materials prepared in the raw material preparation step (S10) for 10 minutes at 40-100°C, and the first kneader mixing step (S21) The inorganic blending agent, the peroxidation crosslinking agent, the pigment, the aging inhibitor, the plasticizer, the flow enhancer, the silane coupling agent, the crosslinking donor, and the ozone inhibitor are added to the raw materials mixed in It includes a second kneader mixing step (S22) mixing at 110 ℃.

At this time, the kneader mixing step (S20) is characterized in that a pressurized kneader is used, the pressing force is 7 to 8kg/cm ² and the rpm is 25 to 35.

The open mill mixing step (S30) is a primary open mill mixing using an open mill for uniform mixing of the peroxidation crosslinking agent in the mixture mixed in the kneader mixing step (S20) at a temperature of 20 to 60°C. It characterized in that it comprises a step (S31), and a second open mill mixing step (S32) remixed for uniform dispersion of the mixture that has gone through the first open mill mixing step (S31).

The mixture formed in the sheet forming step (S40) is characterized in that it is formed into a sheet shape having a width of 100 mm and a thickness of 5 mm.

The sheet extruder used in the continuous manufacturing step of the non-asbestos gasket sheet (S50) is characterized in that it is set to a temperature of 60°C, 70°C, and 80°C depending on the inlet, the middle part, and the discharge part.

The continuous crosslinking step (S60) is characterized in that continuous crosslinking is performed by continuously supplying the extruded sheet to the rotocure at a temperature of 185 to 195°C at a rate of 5M/min.

At this time, the non-asbestos gasket manufactured by the present invention is characterized by having a hardness of 70 HsD, a heat resistance temperature of 350°C or less, a tensile strength of 200 kg/cm ² or more, and an elongation of 20% or more.

The continuous manufacturing method of the non-asbestos gasket according to the present invention does not contain an organic solvent, contains a peroxidation crosslinking agent, is harmless to the human body, and does not include a aging step that is left for a long time for stabilization of toluene. Can be manufactured.

In addition, by more evenly mixing the raw materials of the non-asbestos gasket including the first and second kneader mixing steps and the first and second open mill mixing steps, it is possible to improve the uniformity and bondability of the mixture.

In addition, the mixture can be manufactured in one layer without stacking in multiple layers to produce a desired thickness at a time, and since the extrusion sheet is continuously supplied to RotoCure to continuously crosslink, the efficiency of the production process can be increased.

1 is a flowchart of a method for continuously manufacturing a non-asbestos gasket according to a preferred embodiment of the present invention.
2 is a flowchart of a kneader mixing step according to a preferred embodiment of the present invention.
3 is a flowchart of an open mill mixing step according to a preferred embodiment of the present invention.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms different from each other, and only these embodiments make the disclosure of the present invention complete, and common knowledge in the technical field to which the present invention pertains. It is provided to completely inform the scope of the invention to those who have it, and the invention is only defined by the scope of the claims.

With reference to the accompanying drawings below will be described in detail for the implementation of the present invention. Regardless of the drawings, the same reference numerals refer to the same elements, and "and/or" includes each and all combinations of one or more of the mentioned items.

Although the first, second, and the like are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are only used to distinguish one component from another component. Therefore, it goes without saying that the first component mentioned below may be the second component within the technical idea of the present invention.

The terms used in this specification are for describing exemplary embodiments, and are not intended to limit the present invention. In this specification, the singular form also includes the plural form unless specifically stated in the phrase. As used in the specification, “comprises” and/or “comprising” do not exclude the presence or addition of one or more other elements other than the mentioned elements.

Unless otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used as meanings that can be commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not interpreted ideally or excessively unless explicitly defined specifically.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a flowchart of a method for continuously manufacturing a non-asbestos gasket according to a preferred embodiment of the present invention. A method for continuously manufacturing a non-asbestos gasket according to a preferred embodiment of the present invention will be described in order with reference to FIG. 1.

First, in the raw material preparation step (S10), the solid nitrile-butadiene rubber (NBR), liquid nitrile-butadiene rubber (NBR), and hydrogenated nitrile butadiene rubber (Hydrogenated acrylonitrile butadiene rubber (HNBR)) are weighed. This is the stage of preparing raw materials.

The rubber raw material is characterized by using solid nitrile butadiene rubber and liquid nitrile butadiene rubber in combination to enable continuous extrusion production, and to include hydrogenated nitrile butadiene rubber with excellent compatibility.

Hydrogenated nitrile butadiene rubber has excellent heat resistance, high hardness, and high elasticity, and preferably, zinc methacrylate hydrogenated nitrile rubber (Zinc Methacrylated HNBR) is used to improve workability in an unvulcanized state and physical properties of the rubber after vulcanization.

The solid nitrile butadiene rubber preferably has an acrylonitrile content of 22 to 41% by weight, and a Mooney viscosity [ML(1+4, 100°C)] of 20 to 90. In addition, the liquid nitrile butadiene rubber has an acrylonitrile content of 28% by weight, the hydrogenated nitrile butadiene rubber has an acrylonitrile content of 33 to 42% by weight, and Mooney viscosity [ML(1+ 4, 100°C)] is preferably in the range of 75 to 85.

The rubber raw material is 40 to 60 parts by weight of the solid nitrile-butadiene rubber (NBR), 20 to 40 parts by weight of the liquid nitrile-butadiene rubber (NBR), and , Hydrogenated nitrile butadiene rubber (Hydrogenated acrylonitrile butadiene rubber, HNBR) is prepared including 15 to 25 parts by weight.

Preferably, 50 parts by weight of the solid nitrile butadiene rubber, 30 parts by weight of the liquid nitrile butadiene rubber, and 20 parts by weight of the hydrogenated nitrile butadiene rubber are preferably included.

At this time, the rubber raw material may contain 1 to 30 parts by weight of a modified phenol resin, which improves the flowability of the rubber raw material in the mixing or extrusion process, and improves the abrasion resistance, chemical resistance, oil resistance of the rubber raw material, It is to improve heat resistance.

The following is the kneader mixing step (S20). The kneader mixing step (S20) includes the rubber raw material prepared in the raw material preparation step (S10) and an inorganic compounding agent, a peroxidation crosslinking agent, a pigment, an anti-aging agent, a plasticizer, a flow enhancer, a silane coupling agent, a crosslinking donor, This is a step of putting an ozone inhibitor into a kneader and mixing it.

The kneader used in the kneader mixing step (S20) is a pressurized kneader, and the pressing force is 7-8kg/cm2, and the rpm is maintained at 25-35.

2 is a flowchart of a kneader mixing step according to a preferred embodiment of the present invention. The kneader mixing step (S20) is divided into two steps, and includes a first kneader mixing step (S21) and a second kneader mixing step (S22).

The first kneader mixing step (S21) is a step of adding the rubber raw material prepared by weighing in the raw material preparation step (S10) into the kneader, and mixing it for 10 minutes by setting the temperature at 40 to 100°C. The rubber raw material is first mixed through the first kneader mixing step (S21) to prepare a mixed rubber raw material.

In the second kneader mixing step (S22), the inorganic blending agent, the peroxidation crosslinking agent, the pigment, the anti-aging agent, the plasticizer, the flow enhancer, the silane coupling agent, in the kneader containing the mixed rubber raw material, In this step, the crosslinking donor and the ozone inhibitor are added and mixed. The secondary kneader mixing step (S22) is preferably mixed for 3 minutes at 100 ~ 110 ℃.

The inorganic blending agent includes natural silicate (clay) and natural silica, and is also referred to as an inorganic filler. The natural silicate (clay) contains 50 to 200 parts by weight based on 100 parts by weight of the rubber raw material, and the natural silica includes 20 to 50 parts by weight based on 100 parts by weight of the rubber raw material. The inorganic blending agent improves the performance of heat resistance, strength, shrinkage after vulcanization, good product resistance, and oil resistance.

The silane coupling agent is included for smooth coupling between the inorganic blending agent and the raw rubber material, and contains 2 to 5 parts by weight based on 100 parts by weight of the rubber raw material, and according to the present invention, vinyl triethoxy It is preferred to use a silane (vinyl triethoxy silane coupling agent).

Anti-aging agent is used to prevent oxidation of nitrile butadiene rubber, it is preferable to include a dihydroquinoline-based anti-aging agent, it is preferable to include 1 to 4 parts by weight based on 100 parts by weight of the rubber raw material .

The ozone inhibitor is preferably a phenylenediamine compound, and preferably contains 2 to 5 parts by weight based on 100 parts by weight of the rubber raw material. The ozone inhibitor is for protecting the rubber raw material without breaking the main chain of the polymer of the raw rubber material by reacting with ozone before the ozone reacts with the polymer of the raw rubber material.

The pigment contains 2 to 6 parts by weight based on 100 parts by weight of the rubber raw material, and it is preferable to include a blue pigment of copper-phthalocyanine-beta (Cu-phthalocyanine-β).

The peroxidation crosslinking agent contains 1 to 10 parts by weight based on 100 parts by weight of the rubber raw material, and tert-butyl hydroperoxide, tetramethylbutyl hydroperoxide, isopropylbenzene hydroperoxide ( It is preferable to select and include at least one of isopropylbenzen hydroperoxide), di, tert-butyl peroxide, and dicumyl peroxide.

The crosslinking donating agent is for improving the crosslinking density of the peroxidation crosslinking agent, and contains 1 to 50 parts by weight based on 100 parts by weight of the rubber raw material. The cross-linking donor is methacrylate-based materials such as ethylene glycol dimethacrylate (EDA), butylene glycol dimethacrylate (BDMA), trimethyllopropane methacrylate ( Trimethylolpropane Methacrylate) or Triallyl-based material Triallyl cyanurate, Triallyl isocyanurate, Triallyl phosphate, Triallyl trimellitate Includes one or more of them.

The plasticizer is preferably an ether-based plasticizer having excellent heat resistance, and contains 1 to 20 parts by weight based on 100 parts by weight of the rubber raw material.

The flow enhancer is for preventing the generation of micro air bubbles in the sheet during sheet extrusion manufacturing, and contains 1 to 10 parts by weight based on 100 parts by weight of the rubber raw material, and the flow enhancer is fatty acid It is preferable to include one or more of them.

Referring back to Figure 1, the continuous manufacturing method of the non-asbestos gasket according to the present invention includes an open mill mixing step (S30) after the kneader mixing step (S20).

The open mill mixing step (S30) will be described with reference to FIG. 3. 3 is a flowchart of an open mill mixing step according to a preferred embodiment of the present invention. The open mill mixing step (S30) is to remix the mixture mixed in the kneader mixing step (S20) using an open mill, and the first open mill mixing step (S31) and the second open mill mixing step (S32) ).

The first open mill mixing step (S31) is for uniform mixing of the peroxidation crosslinking agent in the mixture mixed in the kneader mixing step (S20), and a speed of 18 to 21 rpm is maintained at a temperature of 20 to 60°C. While doing, mix the mixture once more using an open mill for 15 to 20 minutes. The roll of the open mill used in the first open mill mixing step (S31) is used with a diameter of 500 mm, and the distance between the rolls is preferably 2 to 10 mm.

The second open mill mixing step (S32) is performed for uniform dispersion of the mixture that has passed through the first open mill mixing step (S31). The second open mill mixing step (S32) is performed at a distance between the rolls of 2 mm for 5 minutes and then at 10 mm for 5 minutes so that the mixture is uniformly dispersed.

The manufacturing method according to the present invention can more evenly mix and disperse the mixture, including the first and second kneader mixing steps and the first and second open mill mixing steps as described above.

The following includes a sheet forming step (S40). The sheet forming step (S40) is a step of forming the mixture uniformly mixed in the open mill mixing step (S30) into a sheet shape and cooling it at room temperature.

The sheet forming step (S40) is formed into a sheet shape in an open mill, and more specifically, it is manufactured in a sheet shape having a thickness of 5 mm and a width of 100 mm. The sheet forming step (S40) is cooled at room temperature, and rearrangement of the mixture formed into the sheet shape is performed during cooling.

The following is a non-asbestos gasket sheet continuous manufacturing step (S50). In the sheet forming step (S40), the mixture first formed into a sheet shape is injected into an extruder to extrude a sheet having a desired thickness by an operator. The extruder may adjust the extrusion speed and sheet thickness according to the sheet-shaped mixture to be introduced, and the extruded sheet may be manufactured by continuously injecting the mixture first formed into a sheet shape.

The extruded sheet preferably has a width of 1250 mm and a thickness of 3 mm, and the thickness of each part of the sheet extruder is adjusted to maintain tolerance.

The temperature of the extruder is set differently depending on the inlet, the middle part, and the discharge part, and they are set to 60℃, 70℃, and 80℃, respectively. In addition, the extruder is capable of extruding within a maximum of 500 kg, and if a mixture of 500 kg or more is added, the extruded sheet thickness may be deformed, so that an extruded sheet having a certain thickness cannot be obtained.

In the continuous crosslinking step (S60), the sheet extruded in the continuous manufacturing step (S50) of the non-asbestos gasket sheet is crosslinked using Rotocure. The extruded sheet is continuously supplied to the Rotocure and is continuously crosslinked at a rate of 5M/min at 185 to 195°C. Including the continuous crosslinking step (S60), the extruded sheet may be continuously crosslinked, and mass production is possible.

After the continuous crosslinking step (S60), in the non-asbestos gasket manufacturing step (S70), the crosslinked sheet is cut according to the standard of the gasket to manufacture a non-asbestos gasket.

The non-asbestos gasket manufactured as described above has a hardness of 70 HsD, a heat resistance temperature of 350°C or less, a tensile strength of 200 kg/cm ² or more, and an elongation of 20% or more.

In the method for continuously manufacturing a non-asbestos gasket according to the present invention described above, a gasket having a desired thickness can be manufactured at a time by manufacturing a gasket in a single layer without laminating the gasket in multiple layers, and a material such as toluene that is harmful to the human body is used. Because it does not include the aging step, which is left for a long time for stabilization of toluene, it can be prepared immediately, thereby reducing production time, thereby improving productivity.

[Example]

50 parts by weight of solid nitrile butadiene rubber, 30 parts by weight of liquid nitrile butadiene rubber, and 20 parts by weight of hydrogenated nitrile butadiene rubber were weighed to prepare a rubber raw material, put in a kneader, and mixed at 80° C. for 10 minutes. 200 parts by weight of clay, 50 parts by weight of natural silica, 40 parts by weight of a crosslinking donor, 6 parts by weight of a peroxidation crosslinking agent, 2 parts by weight of a silane agent, 2 parts by weight of a kneader in which rubber raw materials are mixed. An anti-aging agent, 2 parts by weight of an ozone inhibitor, 2 parts by weight of a flow enhancer, 2 parts by weight of a pigment, and 10 parts by weight of a plasticizer were added and mixed at 100° C. for 3 minutes to obtain a mixture.

The mixture was mixed again using an open mill having a roll diameter of 500 mm, at which time the interval between the rolls was set to 10 mm, and the mixture was mixed for 20 minutes at a temperature of 60° C. at a speed of 21 rpm.

After that, the open mill was mixed for 5 minutes by setting the gap between the rolls to 2 mm, and mixing for 5 minutes by setting the gap between the rolls to 10 mm so that the mixture was uniformly mixed and dispersed.

The uniformly dispersed mixture was molded into a sheet shape, molded to have a thickness of 5 mm and a width of 100 mm, and then cooled at room temperature.

The mixture molded into the sheet was put into an extruder to obtain a compressed sheet, and the discharged compressed sheet obtained a compressed sheet having a width of 1250 mm and a thickness of 3 mm.

The compression sheet was put into a rotocure and crosslinked at 185°C at a rate of 5M/min. The crosslinked sheet was cut according to the standard of the gasket to obtain a non-asbestos gasket.

[Experimental Example]

The physical properties of the non-asbestos gasket prepared according to the example were measured and shown in [Table 1].

Minimum torque (M _L ) 25 lb-in Torque (M _H ) 86 lb-in Scorch time (T ₁₀ ) 1:34 sec Appropriate crosslinking time (T ₉₀ ) 6:11 sec Mooney viscosity (ML ₁₊₄ ,100℃) 54 Hardness (HsA) 100 Hardness (HsD) 70 The tensile strength 210kg / cm ² Elongation 22%

The non-asbestos gasket prepared according to the example had excellent physical properties such as a hardness of 70HsD (100HsA), a tensile strength of 200kg/cm ² or more, and an elongation of 20% or more.

Although the embodiments of the present invention have been described with reference to the above and the accompanying drawings, those of ordinary skill in the art to which the present invention pertains can implement the present invention in other specific forms without changing the technical spirit or essential features. You can understand that there is. Therefore, it is to be understood that the embodiments described above are illustrative and non-limiting in all respects.

S10: Raw material preparation step
S20: Kneader mixing step
S21: 1st kneader mixing step
S22: 2nd kneader mixing step
S30: Open mill mixing step
S31: 1st open mill mixing step
S32: 2nd open mill mixing step
S40: sheet forming step
S50: Non-asbestos gasket sheet continuous extrusion step
S60: continuous crosslinking step
S70: Non-asbestos gasket manufacturing step

Claims (10)

In the continuous manufacturing method of the non-asbestos gasket,
Raw material preparation step of preparing rubber raw materials by weighing solid nitrile-butadiene rubber (NBR), liquid nitrile-butadiene rubber (NBR), and hydrogenated acrylonitrile butadiene rubber (HNBR) ( S10);
The rubber raw material prepared in the raw material preparation step and the inorganic blending agent, peroxidation crosslinking agent, pigment, anti-aging agent, plasticizer, flow enhancer, silane coupling agent, crosslinking donor, ozone inhibitor are added to a kneader and mixed. Kneader mixing step (S20);
An open mill mixing step (S30) of mixing the mixture mixed in the kneader mixing step in an open mill;
A sheet forming step (S40) of forming the mixture mixed in the open mill mixing step into a sheet and cooling it at room temperature;
A non-asbestos gasket sheet continuous manufacturing step (S50) of extruding the sheet manufactured in the sheet forming step by using a sheet extruder to continuously extrude a sheet having a predetermined thickness and width (S50);
A continuous crosslinking step (S60) of crosslinking the extruded sheet manufactured in the continuous manufacturing step of the non-asbestos gasket sheet using Rotocure;
Non-asbestos gasket manufacturing step (S70) of cutting the sheet crosslinked in the continuous crosslinking step according to the standard of the gasket;
Continuous manufacturing method of a non-asbestos gasket comprising a. The method of claim 1,
The rubber raw material prepared in the raw material preparation step (S10) includes 40 to 60 parts by weight of the solid nitrile-butadiene rubber (NBR), and liquid nitrile-butadiene rubber (Nitrile-butadiene) based on 100 parts by weight of the rubber raw material. rubber, NBR) 20 to 40 parts by weight and hydrogenated nitrile butadiene rubber (Hydrogenated acrylonitrile butadiene rubber, HNBR) 15 to 25 parts by weight, characterized in that the continuous manufacturing method of a non-asbestos gasket. The method of claim 1,
Of the raw material preparation step (S10)
The solid nitrile butadiene rubber has an acrylonitrile content of 22 to 41 wt%, a liquid nitrile butadiene rubber has an acrylonitrile content of 28 wt%, and the hydrogenated nitrile butadiene rubber is acrylonitrile ( Acrylonitrile) continuous production method of a non-asbestos gasket, characterized in that the content is 33 to 42% by weight. The method of claim 1,
The kneader mixing step (S20)
A first kneader mixing step (S21) of mixing the raw materials prepared in the raw material preparation step (S10) for 10 minutes at 40 to 100°C, and
The inorganic blending agent, the peroxidation crosslinking agent, the pigment, the aging inhibitor, the plasticizer, the flow enhancer, the silane coupling agent, the crosslinking donor in the raw materials mixed in the first kneader mixing step (S21) , Continuous manufacturing method of a non-asbestos gasket, characterized in that it comprises a second kneader mixing step (S22) of mixing the ozone inhibitor at 100 ~ 110 ℃. The method of claim 1,
The kneader mixing step (S20)
A method for continuously manufacturing a non-asbestos gasket, characterized in that a pressurized kneader is used, the pressing force is 7 to 8 kg/cm ² and the rpm is 25 to 35. The method of claim 1,
The open mill mixing step (S30) is
A first open mill mixing step (S31) of mixing at a temperature of 20 to 60°C using an open mill for uniform mixing of the peroxidation crosslinking agent among the mixtures mixed in the kneader mixing step (S20), and
A method for continuously manufacturing a non-asbestos gasket, characterized in that it comprises a second open mill mixing step (S32) that is remixed for uniform dispersion of the mixture that has gone through the first open mill mixing step (S31). The method of claim 1,
The mixture formed in the sheet forming step (S40) is a continuous method of manufacturing a non-asbestos gasket, characterized in that it is formed into a sheet shape having a width of 100 mm and a thickness of 5 mm. The method of claim 1,
The sheet extruder used in the continuous manufacturing step (S50) of the non-asbestos gasket sheet is set to a temperature of 60°C, 70°C, and 80°C depending on the inlet, the middle part, and the discharge part. Way. The method of claim 1,
The continuous crosslinking step (S60) is a continuous method of manufacturing a non-asbestos gasket, characterized in that the extruded sheet is continuously supplied to the rotocure at a temperature of 185 to 195°C at a rate of 5M/min to continuously crosslink . The method of claim 1,
The non-asbestos gasket has a hardness of 70 HsD, a heat resistance temperature of 350°C or less, a tensile strength of 200kg/cm ² or more, and an elongation of 20% or more.

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