KR102342220B1 - Manufacturing method for rubber product - Google Patents

Abstract

The present method relates to a method for manufacturing a rubber product, and more particularly, relates to a method for manufacturing a rubber product in which process efficiency is improved by stacking and cooling a plurality of molded intermediate products by using a cooling tray without being stuck to each other. The present invention comprises a raw material arrangement step of disposing a raw material having a predetermined size and shape in a lower mold of a molding machine; a product molding step of heating, by the molding machine, the raw material in a state that an upper mold of the molding machine is in close contact with a lower mold thereof, and molding intermediate products according to shapes of the upper mold and the lower mold; and a cooling step of stacking the molded intermediate products on a cooling tray to be cooled, wherein the cooling tray includes a plurality of stacked stackers, and each stacker has a stacking part on an upper surface of which the intermediate product is stacked.

Description

A method of manufacturing rubber products using a cooling tray {MANUFACTURING METHOD FOR RUBBER PRODUCT}

The present method relates to a method for manufacturing a rubber product, and more particularly, to a method for manufacturing a rubber product in which process efficiency is improved by stacking and cooling a plurality of intermediate products formed using a cooling tray so that they do not stick to each other.

In general, rubber raw materials used in rubber molding are made through the manufacturing process sequence such as raw rubber - lowering - mixing - rolling - molding - vulcanization - finishing. The lowering is a process of breaking the raw rubber with a roller to remove the elasticity of the raw rubber and increase the plasticity, and homogenization of rubber particles/cutting of molecules occurs. This makes raw rubber easier to mold.

And mixing is a process of kneading sulfur/vulcanization accelerator/zincification/stearic acid/anti-aging agent/softener/filler (carbon black/silica fine powder, etc.)/coloring pigment as a vulcanizing agent. It is produced using a roller. do.

The rubber raw material made through the manufacturing process as described above is introduced into the raw material supply device in the state of a roll cut to an appropriate width, cut to an appropriate size by a rotating screw, and supplied to the transfer pipe, it is gradually heated to a set temperature and gelled. When it is moved by the transfer screw and put into the cylinder, the raw material in the gel state is pressurized by the piston of the hydraulic cylinder, and is supplied by extrusion to the inlet of the upper mold through the discharge hole.

During the above operation, the lower mold is in close contact with the upper mold by the operation of the injection body or the press, and the raw material introduced into the injection hole is melted inside the upper/lower mold heated to a set temperature to form a desired shape and shape inside the mold. is molded into After injection, the lower mold is returned by a known method, and the desired finished product molded from the mold is removed and produced.

Here, high-pressure steam is circulated inside or an electric heating coil using electrical resistance is built in so that high heat is generated simultaneously in multiple molds during product molding.

On the other hand, as a prior art for this, there is No. 20-0357208 for the Republic of Korea Registration Office, etc. In the conventional rubber injection molding machine nozzle and mold gate coupling structure, the rubber is partially exposed to the outside of the gate and undergoes a vulcanization process. After the vulcanization process is finished, the vulcanized product produced inside the mold is discharged through the discharging process. It is not discharged from the gate and is maintained at the top of the gate and the gate entrance is closed frequently, making it difficult to inject rubber into the mold in the future. In addition, after injection is completed, the maximum separation point of the upper mold from the lower mold is short, and the elevating method is simply a vertical movement method, so workability is reduced or cleaning of rubber that has not been discharged The disadvantage of being very inconvenient has been repeatedly pointed out.

In addition, in the process of cooling the intermediate product or the finished rubber product, it is melted through heating during the molding process and then cooled to form a shape. has a limit that it is not.

The present invention was devised to solve the above problems, and while cooling a large number of molded intermediate products at the same time, the stacked intermediate products do not stick to each other, thereby maximizing space efficiency for cooling, thereby increasing productivity, improving production speed, etc. Its main purpose is to improve efficiency.

The present invention for the purpose of solving the above problems is a raw material arrangement step in which a raw material having a predetermined size and shape is disposed in a lower mold of a molding machine, and in a state in which the upper mold of the molding machine is in close contact with the lower mold, the molding machine is A product molding step of heating the raw material to form an intermediate product according to the shapes of the upper mold and the lower mold, and a cooling step of cooling the molded intermediate product by placing it on a cooling tray, wherein the cooling tray includes a plurality of It includes a stacking table stacked with, and each stacking table is characterized in that it is provided with a stacking unit on the upper surface of which the intermediate product is placed.

In addition, the cooling tray further includes a base including a plurality of rotational coupling portions disposed vertically and arranged at predetermined intervals along the vertical direction, and each of the mounting stands further includes a rotational portion coupled to the rotationally coupling portion at an end thereof, , The cooling step includes the steps of placing the intermediate product on a first placing unit, rotating a second placing unit stacked on top of the first placing unit to overlap the upper part of the intermediate product, and the It may include the step of placing the intermediate product on the piling portion of the second staging table.

In addition, the cooling tray is characterized in that it may further include a rotation fixing means including one end connected to the mounting table, the other end connected to the base, and a body portion having a variable length and a predetermined restoring force.

In addition, the cooling tray includes a hook protruding laterally, the base includes coupling holes arranged at predetermined intervals, the one end includes a hook member hooked on the hook, and the other end includes a hook member hooked on the coupling hole. It is made of a hook member, and the body portion is characterized in that it may be composed of an elastic member.

The present invention having the above steps and features prevents the stacked intermediate products from sticking to each other while cooling a plurality of molded intermediate products at the same time by cooling the intermediate products on the stacking table stacked in plurality, so space efficiency for cooling It has the effect of improving process efficiency, such as increasing productivity and improving production speed.

In addition, through the provision of the pivoting coupling part and the pivoting part, the stacking table is configured so that it can be unfolded and folded through rotation. was maximized.

In addition, through the configuration of the rotation fixing means having a variable length and a predetermined restoring force, the unfolded state and the folded state can be easily maintained, thereby improving the convenience of use.

1 is a block diagram showing each step of a method for manufacturing a rubber product according to the present invention.
2 to 4 are views showing the implementation of the batch of raw materials and product forming steps.
5 to 6 are views showing a specific embodiment of the cooling tray of the present invention.

Since the present invention can have various changes and can have various forms, implementation examples (態樣, aspects) (or embodiments) will be described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

The terminology used herein is only used to describe a specific embodiment (aspect, aspect, aspect) (or embodiment), and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as comprises or consists of are intended to designate that the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification exist, but one or more other features It is to be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

~1~, ~2~, etc. described in the present specification are only to be referred to to distinguish that they are different components, and are not limited to the order of manufacture, and their names in the detailed description and claims of the invention are may not match.

Hereinafter, a method for manufacturing a rubber product according to the present invention (hereinafter, this method) will be described in detail with reference to the accompanying drawings.

This method relates to a rubber product manufacturing method in which process efficiency is improved by stacking and cooling a plurality of intermediate products (2) molded using a cooling tray (3) so that they do not stick to each other, and as shown in FIG. (0) includes a batch step (S1), a product forming step (S2) and a cooling step (S3). And if necessary, it may further include a post-processing step (S4).

Described in detail for each step, first, the raw material (0) arrangement step (S1) is a step of placing the raw material (0) for product molding in the mold of the forming machine 1, more specifically, the lower part of the forming machine 1 This is a step in which the raw material 0 having a predetermined size and shape is disposed in the mold 11 .

2 to 4, the molding machine 1 in this method is a press-type molding machine 1, which includes a lower mold and an upper mold, and the upper mold is lowered and the raw material is in close contact with the lower mold. By heating (0), the shape of the raw material (0) is changed according to the shape of the molding part of the mold to produce the intermediate product (2).

Next, the product molding step S2 is a step in which the product is molded in the molding machine 1 , and more specifically, the molding machine 1 in a state in which the upper mold 12 of the molding machine 1 is in close contact with the lower mold 11 . ) is a step in which the raw material (0) is heated, and the intermediate product (2) is molded according to the shape of the upper mold (12) and the lower mold (11).

Comprehensively explaining the process of molding a rubber product through FIGS. 2 to 4, as shown in FIG. 2, after the raw material 0 is placed in the lower mold according to the arrangement step S1 of the raw material 0, When the molding machine 1 is operated (illustrated by a green button in FIG. 2 ), the lower mold 11 moves and is placed under the upper mold 12 , and then the upper mold 12 descends as shown in FIG. 3 to lower the mold. The raw material (0) is heated in a state in close contact with (11), and then the lower mold (11) is moved horizontally as shown in FIG. 4 to expose the intermediate product (2).

Next, the cooling step (S3) is a step of cooling the molded intermediate product (2), a step of cooling the molded intermediate product (2) by placing it on the cooling tray (3).

The present invention is characterized in that the intermediate product (2) is cooled using a cooling tray (3) unique to the present invention in the cooling step (S3), as confirmed in FIGS. 5 to 6, the cooling tray (3) includes a plurality of stacked stacking tables 31 , and each stacking table 31 is characterized in that it is provided with a stacking unit 311 on the upper surface of which the intermediate product 2 is placed. Through this, the present invention maximizes the space efficiency for cooling by cooling a plurality of molded intermediate products 2 at the same time while preventing the stacked intermediate products 2 from sticking together, thereby increasing productivity and improving process efficiency such as production speed. can be improved

The characteristics of the cooling step (S3) will be described in more detail while describing a specific embodiment of the cooling tray (3). As shown in FIG. 5 , the cooling tray 3 further includes a vertically disposed base 32 , including the above-described mounting table 31 .

For each configuration, the mounting table 31 is a configuration in which rubber products are stacked, and it is preferable to have a structure in which a through hole is formed as much as possible so that the rubber products do not stick to each other during lamination and can be cooled well, as an embodiment. 5 to 6, including a horizontal member, a vertical member orthogonal thereto, and a rim may be configured in a shape similar to a grill. In addition, since it is preferable to provide only a minimum area in which the intermediate product 2 can be mounted, the horizontal member and the vertical member are preferably composed of a thin-diameter wire. This is to ensure that the through hole for cooling can be secured as large as possible.

The piling table 31 is stacked in plurality, and has a rotating structure for more efficient space utilization. As a specific embodiment for this, each pedestal 31 may further include a rotating part 312 at the end. The rotation unit 312 is coupled to the rotation coupling part 322 of the base 32 to be described later so that each mounting table 31 is rotationally coupled with respect to the vertically disposed base 32, thereby each mounting table 31 ) are horizontally arranged and stacked when cooling the rubber product, and rotated vertically and stacked when cooling is not performed. and can be superimposed at an acute angle)

Next, the base 32 is a configuration that provides a foundation on which a plurality of mounting tables 31 can be installed, and is vertically disposed, in a preferred embodiment, a pair of plates can be configured to face each other in parallel have. In the case of the base 32 having a pair of facing structures, the mounting table 31 is disposed between the two plates so that both ends can be rotatably coupled to each plate. In the above, it has been mentioned that the mounting table 31 and the base 32 are rotatably coupled. Obviously, the rotation coupling unit 322 is provided as many as the number of piling tables 31 and is provided at intervals according to the separation distance between the respective piling tables 31 .

In a specific embodiment, the rotating part 312 is composed of a shaft protrusion bent in the horizontal direction at the end of the mounting table 31, and the rotating coupling part 322 may be composed of a shaft protrusion through which the shaft protrusion is inserted. have. 6, it can be seen from the side view of the configuration of the shaft projection and the shaft seolgong. According to the above implementation, it is possible to realize the rotating structure of the mounting table 31 only by bending and punching simple materials.

On the other hand, the above-described rotation unit 312 and rotation coupling unit 322 can provide rotation of the mounting table 31, but cannot fix the rotated state, so that the rotation structure alone cannot maintain the overlapped state. . To this end, the cooling tray 3 of the present invention is characterized in that it may further include a rotation fixing means 33 that allows the position of the mounting table 31 to be maintained in a rotated state.

According to an embodiment of the present invention, as shown in FIGS. 5 to 6 , the cooling tray 3 further includes a rotation fixing means 33 , and the rotation fixing means 33 is on the mounting table 31 . It includes a connected one end 331, the other end 332 connected to the base 32, and a body portion 333 having a variable length and having a predetermined restoring force.

In the above, the restoring force of the body portion 333 means the degree to which the stacking table 31 is horizontally stacked and rotated to maintain the stacked state, and the force and the body to which the stacking table 31 is rotated. When the restoring force of the part 333 is balanced, the state is maintained.

As a specific embodiment of the rotation fixing means 33, as shown in FIGS. 5 to 6, the cooling tray 3 includes a hook protruding laterally, and the base 32 is arranged at a predetermined interval. Including a coupling hole, one end 331 is made of a hook member 313 caught on the hook, the other end 332 is made of a hook member 313 hooked on the coupling hole, the body portion 333 ) may be composed of an elastic member.

In addition, the pedestal 31 may further include a ring member 313 protruding from the opposite end where the rotating part 312 is provided. The ring member 313 may be coupled to the end of the pedestal 31, that is, by a method such as welding to the rim, may be configured as a cylindrical member, and may be configured to have a shape in which an internal through hole is opened in the lateral direction. can

The ring member 313 disturbs the arrangement of the intermediate product 2 by contacting the intermediate product 2 that is being cooled or by touching the mounting table 31 without direct contact with the mounting table 31. can be rotated, and the use of such a ring member 313 can be rotated by holding the ring member 313 by hand or by inserting a bar-shaped driving member into the ring member 313 .

According to this method using the cooling tray 3 described above, the cooling step (S3) is a step of placing the intermediate product (2) on the mounting portion 311 of the first mounting table (31A), the first mounting table (31A) ) by rotating the second mounting table 31B stacked on the upper part of the intermediate product 2, and placing the intermediate product 2 on the mounting portion 311 of the second mounting table 31B. It may include a step of stacking.

Next, the post-processing step (S4) that can be optionally performed includes a process of removing the remainder and foreign substances of the intermediate product (2), and further includes various processing processes for additionally making the intermediate product (2) into a finished product can do.

Specific implementation of this post-processing step (S4) may follow known techniques and general common sense of those skilled in the art, and as can be seen in FIG. 1, the post-processing step (S4) is performed before the cooling step (S3). or may be performed after the cooling step ( S3 ), which may be selected by the operator according to the type of processing operation.

On the other hand, in the process of performing this method, the cooling tray 3 may be composed of a shaft protrusion provided with a rotating part 312 bent in the horizontal direction at the end of the mounting table 31, and the rotation fixing means 33 It has been recalled that it also has a bent portion.

In the description of the present invention, in the process of performing the bending, the restoring force of the shape acts to further disclose a unique press machine for preventing the occurrence of a springback phenomenon in which the degree of bending is reduced.

7 is a view for explaining a press machine according to a further embodiment of the present invention.

As shown in FIG. 7 , the press machine P of the present invention includes a work table P1 , a pressure member P2 and a plurality of support members P3 in order to reduce the springback phenomenon.

First, the work table P1 is shown to be formed in a semicircular shape to mount the raw material on the upper side as shown in FIG. 7 , but may be changed to a different shape according to design specifications.

Next, the pressure member P2 is installed to be spaced apart from the upper portion of the work table P1, and performs a pressing operation by applying pressure to the raw material mounted on the work table P1 through vertical movement. In this case, the pressure member P2 may apply pressure to the raw material mounted on the work table P1 using hydraulic pressure. In a state in which pressure is applied to the raw material through the pressure member P2, the support member P3 supports the outer side of the raw material to fix the raw material. That is, the support member P3 supports the side of the raw material in a state in which pressure is applied to the raw material in order to reduce the springback phenomenon of returning to the original shape after the raw material is deformed through the pressure member P2 .

Specifically, the support member (P3) may include a tip (P31), a support (P32), and a coupling portion (P33) having the same shape as the outer side of the raw material, as shown in FIG. A cooling tank (P31-1) containing a cooling material is included on the outside, and an aqueous solution tank (P32-1) and a heating device (P32-2) containing an aqueous solution are included on the outside of the support (P32), the cooling tank (P31-1) and a pipe (P32-3) connecting the aqueous solution tank (P32-1) is included.

First, the tip P31 may be replaced according to the shape of the outer side of the raw material. In addition, the lower surface of the aqueous solution tank (P32-1) is installed at a higher position than the lower surface of the cooling tank (P31-1). In addition, the upper surfaces of the aqueous solution tank (P32-1) and the cooling tank (P31-1) are provided with injection units that can be opened and closed to replenish the cooling material and the aqueous solution, respectively. In addition, one side of the pipe (P32-3) is attached to the lower surface of the aqueous solution tank (P32-1), and the other side is installed on the lower surface of the cooling tank (P31-1) to cool the water generated in the aqueous solution tank (P32-1). It is installed in an inclined form to flow into the tank (P31-1). At this time, the pipe P32-3 may further include a filter P32-4 to introduce only the water generated in the aqueous solution tank P32-1 into the cooling tank P31-1. And the heating device (P32-2) is attached to the side surface of the aqueous solution tank (P32-1) to maintain the temperature of the aqueous solution tank (P32-1) at 50 °C or more and 100 °C or less.

Next, the cooling material is composed of 20 parts by weight of malic acid, 30 parts by weight of sodium bicarbonate and 1.5 parts by weight of sodium alginate in order to react with water to cool the tip P31 and the raw material. Malic acid is an organic acid that undergoes an endothermic reaction with water. The cooling material according to the present invention may contain 20 parts by weight of malic acid. When malic acid is less than 20 parts by weight, the endothermic reactivity with water is reduced, and malic acid exceeds 20 parts by weight. In this case, there is a disadvantage that may corrode the surface of the tip (P31). And sodium bicarbonate is an inorganic salt that causes an endothermic reaction with water, and 30 parts by weight of sodium bicarbonate may be included in the cooling material according to the present invention. There is a problem that the reactivity is lowered. Sodium alginate is an organic acid that increases endothermic reactivity with water, and 1.5 parts by weight of sodium alginate may be included in the cooling material according to the present invention. There is a problem.

Next, the aqueous solution may be composed of 2 parts by weight of aminosilanized aluminum hydroxide, 10 parts by weight of bisphenol A-type epoxy resin, and 3 parts by weight of poly(oxypropylene)diamine.

Here, aminosilanized aluminum hydroxide is not volatilized by heat, and when aminosilanized aluminum hydroxide is included in less than 2 parts by weight, there is a problem that the aqueous solution according to the present invention cannot express flame retardancy and self-cooling properties, and aminosilane When aluminum hydroxide is included in excess of 2 parts by weight, mechanical properties of the aqueous solution may be reduced, and there is a problem in that the manufacturing cost is excessively increased. In addition, aminosilanized aluminum hydroxide has a characteristic of releasing water when the temperature is 50°C or more and 100°C or less. Therefore, it is preferable that the aqueous solution of the present invention contains 2 parts by weight of aminosilanized aluminum hydroxide.

Next, the bisphenol A type epoxy resin is widely used as a coating agent or lining agent because it exhibits abrasion resistance, oil resistance, waterproofness, etc., and the aqueous solution according to the present invention contains 10 parts by weight of a bisphenol A type epoxy resin to improve abrasion resistance. At this time, when the weight part of the bisphenol A epoxy resin is less than 10 parts by weight, there is a problem that sufficient wear resistance cannot be imparted to the coating layer formed of the coating composition according to the present invention, and when the weight part exceeds 10 parts by weight, the present invention Accordingly, there is a problem that the viscosity of the coating composition is excessively high, which is not suitable for coating. Therefore, it is preferable that the aqueous solution according to the present invention contains 10 parts by weight of the bisphenol A-type epoxy resin. In addition, although the aqueous solution in the present invention is shown to contain a bisphenol A type epoxy resin, a bisphenol type epoxy resin or novolac epoxy resin such as a bisphenol F type epoxy resin and a bisphenol AF type may be used.

Next, poly(oxypropylene)diamine is used to cure the aqueous solution at low temperature. At this time, when the aqueous solution according to the present invention contains less than 3 parts by weight of poly(oxypropylene)diamine, there is a problem that the curing of the aqueous solution does not proceed smoothly, and when the aqueous solution exceeds 3 parts by weight of poly(oxypropylene)diamine, It is difficult to control the curing of the aqueous solution, and there is a problem of deterioration of properties due to the unreacted curing agent. Therefore, it is preferable that the aqueous solution according to the present invention contains 3 parts by weight of poly(oxypropylene)diamine.

That is, the aqueous solution according to the present invention preferably contains 2 parts by weight of aminosilanized aluminum hydroxide, 10 parts by weight of bisphenol A epoxy resin, and 3 parts by weight of poly(oxypropylene)diamine. That is, the cooling material according to the present invention is composed of 20 parts by weight of malic acid, 30 parts by weight of sodium hydrogen carbonate, and 1.5 parts by weight of sodium alginate, and the cooling material increases the temperature of the tip P31 through an endothermic reaction with water generated through an aqueous solution. It is possible to reduce the springback phenomenon of the raw material by lowering it.

Other manufacturing processes not mentioned above are outside the scope to be disclosed in the present invention, and it is assumed to follow well-known techniques, common knowledge of those skilled in the art, and the like.

In addition, the present invention described above with reference to the accompanying drawings is capable of various modifications and changes by those skilled in the art, and such modifications and changes not limited through the claims should be construed as being included in the scope of the present invention. .

1: molding machine
11: lower mold 12: upper mold
2: Intermediate product
3: Cooling tray
31: stockpiling 311: stockpiling
312: rotating part 313: ring member
32: base 322: rotational coupling part
33: rotation fixing means 331: one end
332: the other end 333: body portion

Claims (4)

A raw material arrangement step in which a raw material having a predetermined size and shape is disposed in the lower mold of the molding machine;
a product molding step in which the molding machine heats the raw material in a state in which the upper mold of the molding machine is in close contact with the lower mold, and an intermediate product is molded according to the shapes of the upper mold and the lower mold; and
A cooling step of cooling the molded intermediate product by placing it on a cooling tray;
including,
The cooling tray includes a plurality of stacked stacking tables,
Each pedestal is provided with a piling portion on the upper surface of which the intermediate product is placed,
The cooling tray further includes a base disposed vertically and including a plurality of pivoting coupling portions disposed at predetermined intervals along the vertical direction,
Each of the pedestals further includes a rotating part coupled to the rotating coupling part at an end thereof,
The cooling step is a step of placing the intermediate product on a first mounting portion of the mounting table, rotating the second mounting table stacked on the upper part of the first mounting table to overlap and arrange on top of the intermediate product, and the first 2 Including the step of piling the intermediate product on the staging part of the staging table,
The cooling tray further includes a rotation fixing means including one end connected to the mounting table, the other end connected to the base, and a body portion having a variable length and a predetermined restoring force,
The cooling tray includes a hook protruding to the side,
The base includes coupling holes disposed at predetermined intervals,
The one end is made of a hook member caught on the hook, the other end is made of a hook member hooked on the coupling hole, and the body part is made of an elastic member,
The rotating part is composed of a shaft protrusion bent in the horizontal direction at the end of the mounting table,
Further comprising the step of bending the end of the mounting table in the horizontal direction using a press machine to perform bending to form the shaft projection,
The press machine includes a work bench having a groove on which the raw material is seated, a pressure member installed on the upper part of the work bench and applying pressure to the raw material through vertical movement, and after pressure is applied to the raw material, the outer side of the raw material is supported by supporting the raw material It includes a plurality of support members for fixing,
The support member includes a tip having the same shape as the outer side of the raw material and a support for supporting the tip, and the outside of the tip includes a cooling tank containing a cooling material reacting to water, the outside of the support includes an aqueous solution tank containing an aqueous solution generating water, a heating device for increasing the temperature, and a pipe connecting the cooling tank and the aqueous solution tank to send water to the cooling tank,
The aqueous solution is composed of 2 parts by weight of aminosilanized aluminum hydroxide, 10 parts by weight of bisphenol A-type epoxy resin, and 3 parts by weight of poly(oxypropylene)diamine, and the aqueous solution has an internal temperature of 50° C. or more and 100° C. of the aqueous solution tank of the tip. If less than, generate water,
The cooling material is composed of 20 parts by weight of malic acid, 30 parts by weight of sodium hydrogen carbonate and 1.5 parts by weight of sodium alginate, and reacts with the generated water to cool the tip and the raw material to reduce the springback phenomenon of the raw material. manufacturing method. delete delete delete

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