KR102412842B1 - Method for manufacturing teflon bellows with lhydro-forming process using teflon adhesion molding process - Google Patents

Abstract

The present invention relates to a step of discharging residual air in which a reinforcing pipe having a metal pipe formed on the outside of the Teflon pipe is corrugated by hydraulic pressure, and then the temperature is increased from room temperature to the elastic strain point of Teflon and pressurized for a preset time at a first pressure; , Adhering step of the metal tube and the Teflon tube pressing for a predetermined time at a second pressure higher than the first pressure while increasing the temperature from the elastic deformation point of the Teflon to the plastic deformation point of the Teflon, and the plasticity of the Teflon The step of plastically deforming the Teflon by pressing for a predetermined time at a third pressure higher than the second pressure from the strain point to the temperature just before the maximum heat resistance of the Teflon, and the third pressure from the temperature just before the maximum heat resistance to the maximum heat resistance temperature By providing a method for producing a hydraulically molded Teflon bellows using a Teflon adhesion molding process comprising the step of performing final thermoforming by pressing with a higher fourth pressure, and the step of cooling and solidifying the Teflon, peeling between the metal tube and the Teflon tube By suppressing the adhesion rate, there is an effect that can improve the durability of the bellows.

Description

Manufacturing method of hydraulically formed Teflon bellows using Teflon adhesion molding process TECHNICAL FIELD

The present invention relates to a method for manufacturing a hydraulically molded Teflon bellows using a Teflon adhesion molding process, and more specifically, to a hydraulic pressure molding Teflon bellows using a Teflon adhesion molding process that improves adhesion by suppressing peeling between a metal tube and a Teflon tube it's about how

In general, it protects piping and equipment by absorbing excessive stress applied to the piping line from problems such as expansion and contraction of piping, which can be said to be the blood vessels of modern industrial facilities, vibration problems of driving devices, movement and damage caused by wind pressure and earthquakes, etc. As a means for this, a bellows-type expansion tube capable of absorbing displacement in the longitudinal direction of the pipe is connected at regular intervals and constructed and used.

In particular, the use of acid-resistant bellows is increasing every year due to the expansion, new and larger size of acid-resistant facilities according to the increase in the required amount of stainless-steel.

In the conventional manufacturing method of the bellows expansion tube, the bellows with wrinkled parts was formed by inserting a Teflon tube into the mold device, fastening the mold device, and expanding the tube by pressing a high-pressure liquid (water) inside the tube.

However, the bellows manufactured by the conventional manufacturing method has a disadvantage in that the thickness of the main wall becomes thinner as the length of the tube becomes longer due to pressure and approaches the valleys and mountains forming the corrugation. Due to this, there was a disadvantage that the part of the wrinkle part was easily damaged by pressure and it was difficult to determine the expected replacement time.

Therefore, in order to increase the mechanical strength of the bellows and improve durability, a metal tube is provided to form a bellows integrally on the outside of the tube. As the tube shrinks, it may be separated from the inner circumferential surface of the metal tube, and eventually, the durability of the bellows cannot be increased.

One of the methods proposed in the prior art in order to solve this disadvantage is, "Method for manufacturing hydraulically-molded Teflon bellows" can be heard

This prior document, as shown in FIGS. 1a to 1c, in a Teflon bellows manufacturing method in which a Teflon tube with flared ends is mounted on a pressing device and then compressed and molded into a bellows, the Teflon tube 120 Before the flaring operation, the flange 115 is inserted to be provided on the outside of the Teflon tube 120 and then the step of flaring both ends of the Teflon tube 120 is performed, and the flaring operation of the Teflon tube 120 is performed. After that, a Teflon tube 120 is provided in the mold device 105, and a spacer member is installed to install the spacer member 130 between each intermediate mold 107 positioned on the sidewall of the Teflon tube 120. step; A preliminary expansion step of injecting water into the inside of the Teflon tube 120 after the step to expand the sidewall of the Teflon tube 120 outward while pressurizing it to a low pressure; After the pre-expansion of the Teflon tube 120, the spacer 130 is removed, and water is injected into the Teflon tube 120 to pressurize the upper part of the mold device 105 at a high pressure ( 100) to include an expansion step of secondaryly expanding the Teflon tube 120, and before flaring of both ends to increase the mechanical properties of the Teflon tube 120, outside of the Teflon tube 120 It is made to further include a metal tube installation step of simultaneously forming the metal tube 135 in a state in which it is provided, and the metal tube 135 has the air embedded in the space between the Teflon tube 120 and the Teflon tube 120 to be discharged to the outside. A method is disclosed in which an air hole (137) is configured to be formed. Here, Figure 1a to Figure 1c is a cross-sectional process diagram showing the manufacturing process of the Teflon bellows according to the prior literature, and the reference numbers used in this figure refer to the drawings of the prior literature, so in the description of the present invention to be described later It should be noted that it is independent of the reference numbers in the drawings used.

However, as in the aforementioned prior literature, an air hole is formed in the metal tube to discharge the air contained in the space between the Teflon tube and the outside, and water is injected into the Teflon tube to pressurize the mold device at high pressure. Even though it includes an expansion step of secondarily expanding the Teflon tube by compressing the upper part of the tube with a pressurizing device, permanent deformation occurs even at the forming pressure at room temperature and, unlike the metal tube, which maintains the shape of the formed state, Teflon is permanently deformed at room temperature. Since there is a physical property to return to the original state without this occurring, the metal tube and Teflon cannot be in close contact and peeling occurs.

Therefore, there is a problem that the durability of the bellows is not sufficiently improved in spite of the improvements in the above-mentioned prior art.

Registered Patent No. 10-0963408 (Registration Date: June 04, 2010)

The present invention has been devised to solve the above-described problems, and by suppressing peeling between a metal tube and a Teflon tube to improve the adhesion rate, manufacturing a hydraulic pressure forming Teflon bellows using a Teflon adhesion molding process that can improve the durability of the bellows The purpose is to provide a method.

Although only the main object to be achieved in the present application has been described, it should be noted that, in addition to the above object, objects that can be predicted from the detailed description to be described later are also included within the scope of the object of the present invention.

In a preferred embodiment of the present invention in order to solve the above problems, in a Teflon bellows manufacturing method in which a Teflon tube with flared ends is mounted in a pressing device and then compressed and molded into a bellows, a metal tube is formed on the outside of the Teflon tube Preparing a reinforcing pipe having; flaring both ends of the reinforcing pipe after inserting a flange to the outside of the reinforcing pipe; and fastening at least two intermediate molds spaced apart by a spacer to the reinforcing pipe by a spacer member and then mounting the reinforcing pipe in a mold device, injecting water into the reinforcing pipe and pressurizing it at a low pressure to expand the sidewall of the reinforcing pipe in an outward direction to form a corrugation; Removal, the residual air discharge step of pressing for a predetermined time at a first pressure while increasing the temperature from room temperature to the elastic strain point of Teflon, and increasing the temperature from the elastic strain point of Teflon to the plastic strain point of Teflon while increasing the temperature A third pressure higher than the second pressure from the plastic deformation point of the Teflon to the temperature just before the maximum heat resistance of the Teflon, and the step of adhering the metal tube and the Teflon tube to pressurize for a predetermined time at a second pressure higher than the first pressure. The step of plastically deforming the Teflon by pressing for a predetermined time with, and final thermoforming by pressing with a fourth pressure higher than the third pressure from the temperature immediately before the maximum heat resistance to the maximum heat resistance temperature, and cooling the Teflon to provide a method for manufacturing a hydraulically-molded Teflon bellows using a Teflon adhesion molding process comprising a step of hardening.

In another preferred embodiment of the present invention in order to solve the above problems, in the above-described embodiment, after the finish thermoforming step, the step of shutting off the heat source and slowly cooling to a preset temperature in the furnace for molding the Teflon bellows is further It provides a method for manufacturing a hydraulically molded Teflon bellows using a Teflon adhesion molding process comprising.

In another preferred embodiment of the present invention to solve the above problems, in the above embodiment, the step of discharging the residual air is 3.5 to 4.5 kg/cm 2 while raising the temperature within the temperature range of 15 ° C to 180 ° C It provides a method for manufacturing hydraulically-molded Teflon bellows using a Teflon adhesion molding process, characterized in that pressurizing for 35 to 45 minutes.

In another preferred embodiment of the present invention in order to solve the above-described problems, in the above-described embodiment, the step of adhering the metal tube and the Teflon tube is 4.5 to while increasing the temperature within the temperature range of 181 ° C to 230 ° C. It provides a method for producing a hydraulically molded Teflon bellows using a Teflon adhesion molding process, characterized in that 5.5 kg/cm 2 is pressed for 45 to 55 minutes.

In another preferred embodiment of the present invention in order to solve the above problems, in the above-described embodiment, the step of plastically deforming the Teflon is 5.5 to 6.5 kg while raising the temperature within the temperature range of 231 ° C to 250 ° C. Provides a method for manufacturing hydraulically-molded Teflon bellows using a Teflon adhesion molding process, characterized in that /cm2 is pressed for 45 to 55 minutes.

In another preferred embodiment of the present invention in order to solve the above problems, in the above embodiment, the finish thermoforming step is 6.5 ~ 7.5 kg / ㎠ while raising the temperature within the temperature range of 251 ℃ ~ 260 ℃ It provides a method for manufacturing hydraulically-molded Teflon bellows using a Teflon adhesion molding process, characterized in that pressurizing for 35 to 45 minutes.

In another preferred embodiment of the present invention in order to solve the above-described problems, in the above-described embodiment, the step of slow cooling is 100% from the temperature range of 251 ° C. to 260 ° C. of the finish thermoforming step by blocking the heat source It provides a method for producing a hydraulically molded Teflon bellows using a Teflon adhesion molding process, characterized in that it is slowly cooled while maintaining a pressure of 6.5 to 7.5 kg/cm 2 up to a temperature range of ℃.

According to the manufacturing method of the hydraulically molded Teflon bellows according to a preferred embodiment of the present invention, by suppressing peeling between the metal tube and the Teflon tube to improve the adhesion rate, there is an effect that can improve the durability of the bellows.

It should be noted that only for the main effects obtained by the present invention, in addition to the above-mentioned effects, the derivative effects that can be predicted from the detailed description to be given later are naturally included within the scope of the effects obtained by the present invention.

Before describing the present embodiment in more detail using the drawings, in the drawings and detailed description, identical elements, and elements having the same functions and/or identical technical or physical effects, are assigned the same reference numbers or identified by the same names, and , descriptions of elements shown or described in other embodiments and their functions may be interchangeable with each other or may be applied to each other in other embodiments. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted.
1a to 1c is a cross-sectional view showing the manufacturing process of the Teflon bellows according to the prior art.
Figures 2a and 2b is a cross-sectional view showing a specific process of the manufacturing method of the hydraulic forming Teflon bellows using a Teflon adhesion molding process according to a preferred embodiment of the present invention.
Figure 3 is a condition table showing the process conditions of each process step of the Teflon adhesion molding process among the manufacturing method of the hydraulic pressure forming Teflon bellows using the Teflon adhesion molding process according to a preferred embodiment of the present invention.

Since the present invention can be variously changed and implemented in various forms, specific embodiments are exemplified in the drawings to help the understanding of the present invention and will be described in detail and in detail. However, it will be apparent to one skilled in the art that the embodiments may be practiced without these specific details.

In addition, the following description and drawings are not intended to limit the present invention to specific embodiments, but it should be understood to include all changes, equivalents and substitutes included in the spirit and scope of the present invention, and specifically mentioned otherwise. Unless otherwise noted, features of different embodiments described below may be combined with each other.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement them. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein.

When a component is referred to as being “connected” to another component, it may be directly connected to the other component, but it should be understood that other components may exist in between.

On the other hand, when it is mentioned that a certain element is "directly connected" to another element, it should be understood that the other element does not exist in the middle.

Other words used to describe relationships between elements should be interpreted in a similar manner (eg, "between" versus "directly between," "adjacent" versus "directly adjacent," etc.).

The terms used herein are used only to describe specific embodiments, and are 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 "comprise" or "have" are intended to designate that a feature, number, process, operation, component, part, or a combination thereof described in the specification exists, but one or more other features It is to be understood that this does not preclude the existence or addition of numbers, processes, operations, components, parts, or combinations thereof.

In this regard, directional terms such as "upper", "lower", "below", "front", "behind", "back", "leading", "following", "above", etc. refer to the direction of the illustrated drawings. can be used with reference to As some of the embodiments may be disposed in many different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope defined by the claims, and the detailed description set forth below should not be construed in a limiting sense.

The terms "about", "substantially", etc. to the extent used throughout the specification are used in or close to the numerical value when manufacturing and material tolerances inherent in the stated meaning are presented, and are intended to enhance the understanding of the present invention. To help, precise or absolute figures are used to prevent unfair use by unconscionable infringers of the stated disclosure.

Unless defined otherwise, all terms used herein, including technical or 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 a commonly used dictionary 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

In addition, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and the inventor appropriately defines the concept of the term in order to best describe his invention. Based on the principle that it can be done, it should be interpreted as meaning and concept consistent with the technical idea of the present invention. In addition, if there is no other definition in the technical terms and scientific terms used, it has the meaning commonly understood by those of ordinary skill in the art to which this invention belongs, and the summary of the present invention in the following description and accompanying drawings Descriptions of known functions and configurations that may be unnecessarily obscure will be omitted.

Hereinafter, with reference to the accompanying Figures 2 and 3, a description will be given of a method of manufacturing a hydraulic pressure forming Teflon bellows using a Teflon adhesion forming process according to a preferred embodiment of the present invention.

Figures 2a and 2b are cross-sectional views showing a specific process of the manufacturing method of the hydraulic pressure forming Teflon bellows using a Teflon adhesion molding process according to a preferred embodiment of the present invention, Figure 3 is Teflon according to a preferred embodiment of the present invention It is a condition table showing the process conditions of each process step of the Teflon adhesion molding process among the manufacturing methods of the hydraulic forming Teflon bellows using the adhesion molding process.

First, as shown in Figure 2a, in the manufacturing method of the hydraulic forming Teflon bellows using the Teflon adhesion forming process, the metal tube 120 is provided on the outside of the Teflon tube 125 to prepare the reinforcing tubes 120 and 125.

Next, flanges 115 to the outside of the reinforcing pipes 120 and 125 at both ends of the reinforcing pipes 120 and 125 so that the flanges 115 are integrally mounted on both ends of the reinforcing pipes 120 and 125 after the bellows is formed. ) is inserted and bound, and then both ends of the reinforcing pipes 120 and 125 to which the flange 115 is bound are flared.

Next, with the reinforcing pipes 120 and 125 in the middle, the nuts and bolts are applied to the fastening part 230 in a state where both sides of the two semi-circular intermediate mold parts 200 are abutted to both sides of the intermediate mold part 200 of the other end. Tighten it tightly.

Thereafter, the intermediate mold part 200 is fastened by the number of wrinkles to be formed by repeating the above-described process while maintaining the gap by disposing the gap maintaining part 130 between the intermediate mold parts 200 .

Thereafter, the middle mold part 200 is fastened to the upper mold part 102 at the upper end of the reinforcing pipes 120 and 125 to which the middle mold part 200 is fastened, and the lower mold part 105 is fastened to the lower end of the reinforcing pipes 120 and 125. , the reinforcing pipes 120 and 125 are mounted on the mold device.

Thereafter, as shown in FIG. 2b, by injecting water into the inside of the reinforcing pipe and pressurizing it to a low pressure, the sidewalls of the reinforcing pipes 120 and 125 are wrinkled along the intermediate mold 200 in the outward expansion direction.

Then, the spacing member 200 is removed.

Up to this process, it is the same as the manufacturing method of conventional hydraulically formed Teflon bellows. That is, it is possible to apply the manufacturing method of various hydraulically formed Teflon bellows disclosed in the prior art up to the present stage.

In the process described above, the metal tube 120 and the metal tube 120 and A gap is generated between the Teflon tubes 125 to form an air layer.

In the present invention, through the following process, a Teflon adhesion molding process is performed in which a gap is not generated between the metal tube 120 and the Teflon tube 125 to be in close contact with each other, more specifically as follows.

Referring to FIG. 3 , the air remaining between the metal tube 120 and the Teflon tube 125 is discharged by increasing the temperature from room temperature to the elastic deformation point of Teflon while applying the first pressure for a predetermined time.

In a preferred embodiment of the present invention, the temperature is increased sequentially for 35 to 45 minutes, preferably for 40 minutes, from room temperature, for example, 15° C. to 180° C., where Teflon begins to elastically deform. While increasing the temperature in this way, air pressure is introduced into the reinforcing pipes 120 and 125 to apply the first pressure. At this time, in a preferred embodiment of the present invention, the first pressure is applied within a pressure range of 3.5 to 4.5 kg/cm 2 , preferably a pressure of 4 kg/cm 2 is applied.

As a result, the air remaining between the metal tube 120 and the Teflon tube 125 is discharged, and the metal tube 120 and the Teflon tube 125 start to come into close contact.

In addition, by increasing the temperature sequentially while applying pressure for a certain period of time under the above-described conditions, the non-uniform elongation of the Teflon tube 125 is suppressed and uniformly elongated so that the independent between the metal tube 120 and the Teflon tube 125 is There is also an effect of evenly adhering without air pockets being generated.

Thereafter, while applying a second pressure greater than the first pressure for a predetermined time, the temperature is increased from the elastic deformation point of the Teflon to the plastic deformation point of the Teflon, thereby bringing the metal tube 120 and the Teflon tube 120 into close contact.

In a preferred embodiment of the present invention, the elastic deformation initiation temperature of Teflon, for example, from 181 ° C, where Teflon begins to be elastically deformed to 230 ° C, where Teflon begins to be plastically deformed, is sequential for 45 to 55 minutes, preferably for 50 minutes. raise the temperature to As described above, while the temperature is increased, the air pressure introduced into the reinforcing pipes 120 and 125 is increased and maintained to a second pressure higher than the first pressure. At this time, in a preferred embodiment of the present invention, the second pressure is applied within a pressure range of 4.5 to 5.5 kg/cm 2 , preferably a pressure of 5 kg/cm 2 is applied.

As a result, the Teflon tube 125 is completely elastically deformed, so that the metal tube 120 and the Teflon tube 125 are completely in close contact. Elastic deformation refers to a deformation range to the extent that it is restored when the heat source is removed after being deformed. Here, it is a point in the process of raising the Teflon tube 125 to the maximum heat-resistant temperature and adhering it to the metal tube 120 at the highest elongation. .

Thereafter, the Teflon tube 125 is plastically deformed from the plastic deformation point of the Teflon to the temperature just before the maximum heat resistance of the Teflon by pressing at a third pressure higher than the second pressure for a preset time.

In a preferred embodiment of the present invention, the plastic deformation initiation temperature of Teflon, for example, the temperature just before the maximum heat resistance of Teflon at 231 ° C at which Teflon is plastically deformed, for example, 250 ° C. for 45 to 55 minutes, preferably 50 Increase the temperature sequentially over a period of minutes. As such, while increasing the temperature, the pressure of the air introduced into the reinforcing pipes 120 and 125 is increased to a third pressure greater than the second pressure and maintained. At this time, in a preferred embodiment of the present invention, the third pressure is applied within a pressure range of 5.5 to 6.5 kg/cm 2 , preferably a pressure of 6 kg/cm 2 is applied.

When the heat source is blocked and cooled in the elastic deformation range of Teflon, that is, less than 230 ° C., the Teflon tube 125 is partially restored and there is a risk that an air layer may be formed between the Teflon tube 125 and the metal tube 120 again. In the present invention, plastic deformation The Teflon tube 125 is plastically deformed by pressing for a predetermined time at a third pressure higher than the second pressure from the point to the temperature just before the maximum heat resistance of the Teflon. As a result, since the Teflon tube 125 is plastically deformed and not restored to its previous state, the adhesion between the metal tube 120 and the Teflon tube 125 is maintained.

Thereafter, the final thermoforming is performed by pressing at a fourth pressure higher than the third pressure from the temperature just before the maximum heat resistance of Teflon for a predetermined time to the maximum heat resistance temperature.

In a preferred embodiment of the present invention, the temperature just before the maximum heat resistance of Teflon, for example, from 181° C., where Teflon begins to elastically deform, to 260° C., the maximum heat resistance temperature of Teflon, for 35 to 45 minutes, preferably for 40 minutes, sequentially raise the temperature. As described above, while increasing the temperature, the pressure of the air introduced into the reinforcing pipes 120 and 125 is increased and maintained to a fourth pressure higher than the third pressure. At this time, in a preferred embodiment of the present invention, the fourth pressure is applied within a pressure range of 6.5 to 7.5 kg/cm 2 , preferably a pressure of 7 kg/cm 2 is applied.

In this step, the temperature is raised to 260 ° C, which is the maximum heat resistance temperature of Teflon, and the pressure is also raised to the maximum process pressure of 7 kg/cm 2 and maintained for 40 minutes, for example, until the part with weak adhesion in the previous step. tightly adhere.

Above, the change in pressure in the above-described process may lead to non-uniform growth of Teflon, so it is preferable to keep the pressure at a preset static pressure by paying attention to the increase in pressure according to temperature.

After finishing the above-mentioned finishing thermoforming step, the heat source is shut off and the predetermined temperature in the furnace for forming the Teflon bellows is slowly cooled while maintaining the fourth pressure up to a temperature range of, for example, 100°C.

That is, since the maximum heat resistance temperature is raised, rapid cooling may cause cracks or non-uniformity of the metal tube 120 and the Teflon tube 125. Slow cooling by natural cooling in the furnace with the heat source shut off desirable.

As described above, in the present invention, by gradually increasing the temperature and pressure in accordance with the physical properties according to the temperature and pressure of Teflon, and gradually bringing the metal tube 120 and the Teflon tube 125 into close contact, a uniform and complete form of adhesion characteristics can be obtained. There is an effect that can suppress the play due to restoration by the plastic processing of the Teflon tube (125).

The invention is not limited except by the appended claims and their equivalents. With respect to the various functions performed by the aforementioned components or structures, the terminology used to describe these components, unless otherwise indicated, refers to It is intended to correspond to any component or structure that performs (ie, is functionally equivalent to) the specific function of the described component, although not structurally identical to the disclosed structure.

Further, the following claims are incorporated into the detailed description, with each claim standing on its own as a separate exemplary embodiment. While each claim may stand on its own as a separate exemplary embodiment (although a dependent claim may refer to a specific combination with one or more other claims in a claim), other exemplary embodiments may also exist in mutually dependent or independent claims. It should be noted that a combination of subject and dependent claims may be included. Such combinations are suggested herein unless it is stated that a particular combination is not intended. Furthermore, it is intended to cover the features of a claim to any other independent claim as well, even if this claim is not directly dependent on the independent claim.

While various exemplary embodiments have been disclosed, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention, which may achieve some of the advantages of the concepts disclosed herein. It will be apparent to those skilled in the art that other components performing the same function may be appropriately substituted. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. It should be noted that features described with reference to a particular figure may be combined with features of other figures even in features not explicitly mentioned. Such modifications to the general concept of the invention are intended to be covered by the appended claims and their legal equivalents.

100: pressurization device
102: upper mold part
105: lower mold part
110: pressure nozzle
115: flange
120: metal tube
122: wrinkle part
125: Teflon tube
130: gap maintaining part
200: middle mold part

Claims (7)

In the method for manufacturing a Teflon bellows, in which a Teflon tube with flared ends is mounted in a pressure device and then compressed and molded into a bellows,
Preparing a reinforcing pipe having a metal pipe on the outside of the Teflon pipe;
flaring both ends of the reinforcing pipe after inserting a flange to the outside of the reinforcing pipe;
Fastening at least two intermediate molds spaced apart by a spacer to the reinforcing pipe and then mounting the reinforcing pipe to a mold device;
forming a corrugation by injecting water into the inside of the reinforcing pipe and pressurizing it at a low pressure to expand the sidewall of the reinforcing pipe in an outward direction;
A step of discharging residual air by removing the spacer and pressing for a predetermined time at a first pressure while increasing the temperature from room temperature to the elastic strain point of Teflon;
Adhering the metal tube and the Teflon tube by pressing for a predetermined time at a second pressure higher than the first pressure while increasing the temperature from the elastic strain point of the Teflon to the plastic strain point of the Teflon;
plastically deforming the Teflon by pressing for a predetermined time at a third pressure higher than the second pressure from the plastic deformation point of the Teflon to the temperature just before the maximum heat resistance of the Teflon;
performing finish thermoforming by pressing at a fourth pressure higher than the third pressure from the temperature just before the maximum heat resistance to the maximum heat resistance temperature;
Cooling the Teflon to harden
A method of manufacturing hydraulically-formed Teflon bellows using a Teflon contact molding process comprising a.
The method of claim 1,
After the finishing thermoforming step, the method for producing a hydraulically formed Teflon bellows using a Teflon adhesion molding process further comprising the step of shutting off the heat source and slowly cooling to a predetermined temperature in a furnace for molding the Teflon bellows.
The method of claim 1,
In the step of discharging the residual air,
A method of manufacturing hydraulically-molded Teflon bellows using a Teflon adhesion molding process, characterized in that 3.5-4.5 kg/cm 2 is pressed for 35-45 minutes while raising the temperature within a temperature range of 15° C. to 180° C.,
The method of claim 1,
The adhesion step of the metal tube and the Teflon tube,
A method of manufacturing hydraulically-molded Teflon bellows using a Teflon adhesion molding process, characterized in that 4.5-5.5 kg/cm 2 is pressurized for 45-55 minutes while raising the temperature within the temperature range of 181 ° C to 230 ° C,
The method of claim 1,
The step of plastically deforming the Teflon,
A method of manufacturing hydraulically-molded Teflon bellows using a Teflon adhesion molding process, characterized in that 5.5-6.5 kg/cm 2 is pressed for 45-55 minutes while raising the temperature within a temperature range of 231° C. to 250° C.,
The method of claim 1,
The final thermoforming step is,
A method of manufacturing hydraulically-formed Teflon bellows using a Teflon adhesion molding process, characterized in that while increasing the temperature within the temperature range of 251 ° C to 260 ° C, pressurizing 6.5 to 7.5 kg/cm 2 for 35 to 45 minutes,
3. The method of claim 2,
The slow cooling step is
Teflon adhesion molding process, characterized in that the heat source is cut off and the temperature range of 251 ° C to 260 ° C in the final thermoforming step is cooled to a temperature range of 100 ° C, while maintaining a pressure of 6.5 to 7.5 kg / cm 2 A method of manufacturing a hydraulically molded Teflon bellows using

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