KR101205870B1 - Highpresser Gas Hose - Google Patents

Abstract

In the present invention, nitrile butadiene (NBR) rubber is introduced into an injector of a rubber high pressure hose manufacturing extruder and extruded into a tubular shape to form a tubular rubber inner layer 1 (extrusion outer diameter 11.9 mm) having a hose inner diameter of 9.5 mm, It is transferred to the front side, and is transferred to the wire reinforcement layer braiding device installed on the front side to form the wire reinforcement layer 2 (braiding outer diameter 13.1mm) by braiding 2-5 strands of steel wire having a diameter of 0.25-0.30 mm to the outside of the rubber inner layer 1. Then, the synthetic rubber selected from chloropolyethylene (CPE), chloroprene (CR), styrene butadiene (SBR), ethylene propylene (EPDM) and the like is transferred to a coating apparatus installed on the front side of the wire reinforcing layer 2. After coating (coating) and laminating the rubber outer layer (3), which is (cover outer diameter 15.5 mm), it is transferred to a rim installed on the rear side to form a urethane outer layer (4) (product outer diameter 16.5 mm), and then Manufactured by passing through the installed drawer It relates to a manufacturing method of a high pressure hose for city gas.

Description

Manufacturing method of high pressure hose for city gas {Highpresser Gas Hose}

The present invention braids a common WIRE wire to a tube of acrylonitrile / putadiene copolymer rubber (NBR) having good airtightness, and has a cover of acrylonitrile / putadiene copolymer rubber (NBR) or a CPE-based rubber material thereon. Next, the high pressure hose for city gas coated by adding various colors to a thermoplastic resin (polyurethane, polyamide, polyethylene, polystyrene, polyvinyl chloride, polypropylene, polyester, etc.) such as polyurethane or nylon It relates to a manufacturing method.

In general, the high pressure hose is a kind of pipe (hose) used as a passage used to withstand the high pressure (hydraulic pressure, water pressure, air pressure) of the fluid or gas flowing in the hose to move smoothly to a desired place. The reinforcing layer consists of a reinforcing layer and an outer layer using steel wires.

High pressure hoses are used for automobiles, construction machinery and hydraulic machinery, paint sprayers, city gas containing oil or gas under high pressure for a long time, and used for flow.

In general, the manufacturing method of the high-pressure resin hose is made of synthetic resin as a main raw material, reinforced with braiding on an extruded tube, coated with a thermosetting resin, and coated with urethane through a certain drying time. Looking at the manufacturing process as described above by the process as follows.

1st process

Raw materials received (raw materials): Nylon resin, polyester resin, polyester yarn, nylon yarn, wire thermosetting adhesive diluent, hardener

Second Step

Tube Extrusion Process

Third step

Braiding Process-WIRE, TEXTILE Braiding

Fourth step

Thermosetting resin bonding The thermosetting adhesive resin is applied to a braided tube with a curing agent and a diluent, followed by drying for a certain time (at least 1 hour at room temperature).

5th process

Polyurethane Bonding Process

Extrusion coating is performed on the thermosetting resin applied to the tube.

The high-pressure resin hose manufactured in the above process is widely used in hydraulic actuators using hydraulic cylinders, aircraft, automobiles, ships, and industrial automation equipment. However, after forming the tube in the manufacturing process, using a curable resin to close contact between the tube and the reinforcement layer or close contact with the tube and the reinforcement layer with excessive tension causes hardening of the tube or early destruction of the tube to cause many problems in use. It has caused.

As the rubber material for producing the rubber material high pressure hose, chloroprene rubber, acrylonitrile / putadiene copolymer rubber (NBR), acrylic rubber and nitrile group-containing high saturated rubber (e.g. cured NBR) are known.

The process of producing a general high pressure rubber hose is as follows.

The rubber extruder passes through a rubber extruder on a mandrel (for internal diameter maintenance) made of nylon synthetic resin (tubes), passes through a braiding machine on the front side, forms a reinforcing layer with a common steel wire on the tube, and then passes through a rubber extruder to cover rubber Apply to proceed to the next step. Next, polypropylene (pp) is applied and the rubber is molded by applying heat to the vulcanization kiln for about 3 hours with steam. By peeling off the PP again and taking out the mandrel inside the tube, the rubber high pressure hose product is completed. This process is a general process for producing a general rubber high pressure hose.

However, it flows into the hose at high pressure and vaporizes to form fine bubbles in the hose, affecting the material inside the hose, and passing or affecting some substances forming a structure between the polymers of the polymer composition. Or gas leaks to the outside through the hose, or even the above phenomenon accumulates, causing the hose to break, causing safety accidents or impairing work efficiency. There have been many studies to solve this problem.

For example, Korean Laid-Open Patent Publication No. 1998-67404 discloses that after applying a thermoplastic adhesive to a tube body made by extrusion molding nylon or elastic polyester resin, braided polyester fibers are braided, dried, and then polyurethane. In the resin, a method of manufacturing a pressure resistant triple hose by coating a wear-resistant resin first and a flexible resin second is disclosed.

Published Patent Publication No. 1998-032081 discloses a gas barrier film having a maximum shrinkage of 3.5% or less and comprising at least a polyamide film and an inorganic deposited layer laminated thereon,

Publication No. 2002-0075309 discloses an outer layer formed from polyamide in a radial direction from the outside, a layer formed from copolyamide, a layer formed from EVOH, an inner layer formed from polyamide, formed from copolyamide. A description of a multilayer tube which includes and is in contact with each other at their respective contact areas,

Publication No. 2002-0050731 discloses 0 to 80 parts by weight of polyamide selected from PA6, PA66, PA6 / 66 and mixtures thereof, 0 to 100 parts by weight of polyamine-polyamide copolymer and PA11, PA12, PA612, PA1012 , Two or more composites comprising a layer made from a molding composition comprising 0 to 80 parts by weight of a polyamide selected from PA1212 and mixtures thereof and a layer made from a molding composition comprising an ethylene vinyl alcohol copolymer,

Korean Patent Laid-Open Publication No. 2001-0025242 discloses a PE comprising coextruding a raw film, simultaneously stretching the film, and heat treating the film at a temperature of 170 to 250 ° C. for a heat treatment time of 3 to 8 seconds. A method of making a multilayer film such as / binder / EVOH / binder / PET is described,

Korean Patent Application Publication No. 98-67404 discloses a wear resistance primarily in a polyurethane resin after braiding and drying a polyester fiber after applying a thermoplastic adhesive to a tube body made by extrusion molding a nylon or elastic polyester resin, and then braiding polyester fibers. A method of manufacturing a pressure resistant hose for coating a resin and coating a flexible resin with a secondary resin to manufacture a pressure resistant triple hose is described.

Published Patent Publication No. 10-98-69690 discloses a high-pressure resin hose manufactured by adhering high-strength yarn to a tube and adsorbing the braided tube using a bond instead of a resin required for adhesion to form a coating on the high-strength yarn. The manufacturing method of the present invention is described, and the other Republic of Korea Patent Publication No. 10-252137, extrusion apparatus and method and tubular products, the Publication No. 10-0175521 is a preform in the form of hoses or pipes from the extrudable plastic Extruded head for production is registered in Korea Utility Model Publication No. 1993-0003320, double-extrusion apparatus for combustion pipes, and registered in Korea Patent Publication No. 20-0226256. No. 20-0274857 is applied to the side of the fabric that is located inside the hose from the fabric by applying heat to the pressing surface High pressure hose is formed by forming a micro hole in the cross section of the fabric to the pressing surface

Korean Utility Model Publication No. 94-19529 discloses that a spring coil is wound around a hose to cover a cable but the weight is heavy and the tensile force is weak and spring coils and synthetic resin are broken by repetitive bending due to physical properties And,

Japanese Patent Application No. 88-136808 describes a high pressure hose made of vulcanized rubber in which a zinc composition is mixed with zinc methacrylate and an organic peroxide, and Korean Patent Publication No. 92-9944 has a reinforcing iron core coated with a urethane through a shaft. It is disclosed a method of mutually fusion welding at high temperatures as the urethane tape is extruded and molded while rotating in a spiral,

Korean Patent Application No. 10-2000-0067179 discloses a method of manufacturing a high pressure hose mainly made of synthetic resin. Patent Publication No. 10-2003-815 discloses a process in which a manufacturing apparatus and a general hydraulic hose manufacturing method are mixed. It can be seen.

While the conventional technology has improved durability from bending, damage, and flame, its color is limited, which is not suitable for the interior of the room, and also has a disadvantage that it is hard to erase when contaminants are put on the outer skin. Because of me, there are consumer complaints.

The present invention is to prevent gas safety accidents caused by gas leakage, which is the biggest shortcoming of the existing domestic city gas hose, and to prevent gas leakage accidents caused by bending, which is a structural problem of the hose.

In addition, there is a purpose to enable safe use of gas is protected from external impacts such as cuts and cuts than conventional hoses that are easily cut.

The present invention in view of the conventional problems as described above, in order to reduce the fatigue of the product and to maintain the flexibility of the product to maintain a high pressure for the city gas to be composed of a rubber inner layer, a wire reinforcing layer, a rubber outer layer, a urethane outer layer therein. It is a problem solving means of this invention to provide the manufacturing method of a hose.

The present invention is designed as a triple airtight tube (tube, cover, urethane cover), improves airtightness, is a product using a rubber is more stable than the prior art of the PVC material which is easily damaged by a small external impact, and also for cutting It is also flexible and strong because it is braided on the tube by general steel wire (0.3mm ~ 0.25mm), and it protects the inside of the hose from the flame or heat by using special flame-retardant rubber material. It can be protected from direct damage from the flame, and the color of the conventional rubber high pressure hose is very limited.

While the basic color of the rubber is black and the bright color (ivory color) is very difficult to manage because of the contamination on the outer surface of the hose, the urethane resin cover of the high-pressure resin of the present invention is easily contaminated and is often stained. In terms of interior design, it can be easily harmonized with the existing interior color such as molding color of home, furniture refrigerator or gas stove, etc. There is a merit that can be produced to satisfy the needs of consumers as much as possible.

1 is a detailed view of a high pressure hose for city gas of the present invention

The present invention, in order to achieve the above object, the present invention has a high primary sealing effect and safety of the rubber eye layer (1), the wire reinforcing layer (2) coated on the outside of the rubber eye layer (1) is external as a general steel wire braid Improved safety from impact (cutting, bending, rupture, etc.), and rubber outer layer, which is made of synthetic rubber selected from chloropolyethylene (CPE), chloroprene (CR), styrene-butadiene (SBR), and ethylene propylene (EPDM) (3) by coating (coating) on the outside of the wire reinforcing layer (2) to improve the safety of the secondary hermetic effect, the urethane outer layer (4) coated (coated) on the outside of the rubber outer layer (3) is a thermoplastic synthetic resin The safety of the tertiary hermetic effect of <urethane, elastomer, vinyl chloride, nylon, etc.> and the superior design of the interior design, and the manufacturing method of the high-pressure hose for city gas heat-resistant with flame-resistant rubber material .

Looking at the characteristics of the high-pressure hose for city gas manufactured in the manufacturing method of the high-pressure hose for city gas of the present invention,

1. Confidentiality

Conventional city gas hose is composed of a double hermetic structure (tubing, cover), but the present invention is designed as a triple hermetic (tube, cover, urethane cover), the structure of the other company's product is also composed of a double hermetic It is easy to see that the confidentiality is greatly improved.

2. Safety from external shock

The reason that it doesn't break under strong impact, crushing, or severe bending is the property of rubber.

The present invention can make a big difference from the product of the PVC material of other companies that are easily damaged even by a small external impact.

In addition, it can be a flexible yet strong product because it is braided by general steel wire (0.3mm ~ 0.25mm) on the tube even in the durability against cutting.

3. Heat resistance

The use of a special flame retardant rubber material protects the inside of the hose from flames and heat, as well as from the upper urethane coating, primarily protecting it from direct damage from heat and flame. In the case of other companies' products, it is very dangerous because it melts when exposed to heat or flame.

The present invention can be seen to be very safe in view of the nature of the rubber material that is primarily protected and not melted urethane.

4. Design Excellence

High pressure hose cover for city gas is very limited in color. The basic color of the rubber is black and the bright color (ivory color) has a disadvantage in that it is very difficult to manage because of contamination on the outer surface of the hose.

The urethane outer layer of the present invention has the advantage of being able to compensate for these disadvantages that are easily contaminated and timely.

In terms of interior design, it is easy to harmonize with existing interior colors such as molding color of home, furniture refrigerator, gas stove, etc., and it is easy to produce various colors of products that ordinary consumers demand. It is expected to meet the needs of the best.

Looking at the manufacturing method of the high-pressure hose for city gas of the present invention, (urethane, elastomer, nylon resin material to improve the adhesion of the non-material)

In general rubber hose, the last process that maintains the inner diameter by using resin product called Mandrerel is to take out Mandrerel.

This creates a hose hole and becomes a product. After that, when the tensile force is applied to the hose increases, it can bring about better adhesion between the two materials.

In other words, if the tension is maintained at 20kgf / ㎠ or more on the rim, the product is stretched, so the outer diameter of the product is reduced by about 0.5mm ~ 1mm, at this time, the Urae charcoal coating in the increased (reduced outer diameter) state. After that, when the hose is passed through the caterpillar, the tensile force is lost, so the increased hose is returned to its original state. The reduced outer diameter returns to its original position, whereby the outer surface of the rubber and the inner surface of the urethane may be in close contact with each other to produce an adhesive effect.

As shown in Fig. 1, the structure of the present invention is laminated from the inside into the rubber inner layer (1), the wire reinforcing layer (2), the rubber outer layer (3), and the urethane outer layer (4). ,

The reinforcement layer uses steel strands 2-5 strands outside the diameter of 0.25-0.30 mm.

The rubber inner layer (1) and the rubber outer layer (3) should adhere well, and the peel strength should be 1.2 KN / m (3.1 kg / 25mm) or more. The rubber outer layer 3) and the urethane outer layer (4) should adhere well without play.

Hose inner diameter is 6.3mm, 9.5mm, 12.7mm and the tolerance is ± 0.7mm.

The present invention is suitable for gas resistance test and the tensile strength should be 14.7KN / m (7.5Kgf / 5mm) or more and the tensile strength drop rate should be 20% or less after 48 hours of air heating aging test at 70 ℃. After 24 hours of liquefied petroleum gas liquid at 40 ° C, liquefied petroleum gas liquid at 40 ° C and air at -25 ° C, respectively, the volume change rate is within -3 to 10%.

In the pressure resistance test conducted at a pressure of 3 MPa, there is no abnormality and the burst pressure is 4 MPa or more.

There is no leak in the airtight test conducted at a pressure of 0.2 MPa,

No cracks or swelling when bent at minimum bending radius after maintaining for 48 hours in 120 ± 2 ℃ air,

When a hose with a minimum length of 0.5 m is bent to form an acute angle of 45 degrees at 2/3 of the hose length after 24 hours at a temperature of -25 ℃ ± 3 ℃, there is no crack or breakage.

After 96 hours at the test temperature of 40 ± 2 ℃ and ozone concentration of 50 ± 5pphm, there is no crack or crack by bending at the minimum bending radius.

The gas permeation through the hose up to 30 hours after elapse of 24 hours with the propane gas of more than 98% purity contained in a 90 cm hose at a temperature of 35 ± 0.5 ° C, 3 ml or less per hour, 3 ml or less for 9.5 mm, 5 ml or less, 12.7 mm Is less than or equal to 7 ml,

Flame-retardant test with burner is performed so that the hose does not burn out for more than 5 seconds,

Using a cutting tester with a 500 mm blade length, place the hose at a distance of 100 mm from the fixed end of the blade, hold the 6 kg weight at the other end for 5 minutes, and ensure no leakage during the leak test.

The material of the urethane outer layer formed on the outside of the present invention is a kind of thermoplastic resin, polyamide resin, polyurethane resin, TPU (Thermoplastic polyuretane elastomer), polyvinyl chloride, polyvinylidene chloride, polyethylene, polystyrene, polyethylene terephthalate As synthetic resins such as polypropylene, its molding is easy and its color can come out in various colors, so it can be coated with various materials.

Rubber inner layer (1) of the present invention has a high gas tightness to use nitrile butadiene (NBR) rubber,

The material of the rubber outer layer 3 is to use any one of synthetic rubbers selected from chloropolyethylene (CPE), chloroprene (CR), styrene-butadiene (SBR), ethylene propylene (EPDM), and the like.

Hereinafter, the present invention will be described in detail with reference to examples.

Example

Nitrile butadiene (NBR) was added to the feeder of the high pressure hose manufacturing extruder and extruded into a tubular shape to form a tubular rubber inner layer (1) having a hose inner diameter of 6.3 mm.

It is transferred to the wire reinforcing layer braiding device installed on the front side to form a wire reinforcing layer (2) by braiding two to five strands of steel wire 0.25 ~ 0.30mm in diameter to the outside of the rubber eye layer (1),

It is transferred to a rubber extrusion device installed on the front surface and coated (cover coating) on the outside of the wire reinforcement layer 2 with chloropolyethylene (CPE), and the rubber outer layer 3 is laminated, followed by the production process of general rubber hydraulic hose. After vulcanization, demolition

The tube is transferred to a feeder installed at the rear of the resin extruder and maintained at a tensile force of 10 kgf / cm 2 or more. At this time, the manufactured tube is tensioned. In this case, the polyurethane resin is coated (coated) while the product outer diameter of the tube is stretched from 0.5 mm to 1 mm. To form a urethane outer layer (4), at this time, because the tensile force is lost when passing through the intake (catafiller) installed in the front, the stretched hose is restored to its original size and the outer diameter is returned to its original position and the rubber outer layer (3) and The urethane outer layer (4) was to be in close contact with the rubber outer layer (3) and the urethane outer layer (4) to be able to see the effect of the adhesion is lost to produce a high-pressure hose for city gas.

Experimental Example

Existing city gas hose products were randomly selected and compared with high-quality hoses of good quality in the general domestic city gas hoses of our products.

City Gas Hose Self-Test Report division Test Items Exam conditions City Gas Corporation Standards Test result

Inner rubber

1. Tensile strength MIn. 14.7 KN / m 16.8KN / m
2. Gas resistance
-20 ℃ X LPG X 24hrs 1.2 40 ℃ X LPG X 24hrs Volume change rate -3 ~ 10% 1.5 -25 ℃ X Air X 24hrs 0.8 3. air aging 70 ℃ X 48hrs Tensile Strength: MAX.20% 5.3% Floor Total Peel strength Min.3.1Kg / Inch 4.6Kg / Inch








hose



1.pressure resistance 3Mpa 30.6kgf / ㎠ No abnormality in the bracket and hose cross section No leak 2. Bursting MIn. 4Mpa
40.8kgf / ㎠ 115.8Kgf / ㎠ 3. Confidentiality 0.2Mpa 2kgf / ㎠ No leakage of air No leak 4. Minimum bending (high temperature) 120 ± 2 ℃ X 48hrs X Minimum Bending (70mm) No cracks and swelling No cracks and swelling 5. Minimum bending (low temperature) 0.5m X -25 ± 3 ℃ X 24hrs X 3/2 ± Point 45 Degree Bend No crack or damage No cracks or breakage 6. Ozone Resistance 40 ± 2 ℃ X 50pphm X 96hrs X Minimum Bend (70mm) No crack or damage No crack or damage 7. Gas permeability 0.9m X 35 ± 0.5 ℃ X 98% Propane X 24 ~ 30hrs Max.5ml / 1hrs 3.3ml / 1hrs 8. Flame retardant Burner Use No flame burning for more than 5 seconds 2 seconds 9. Cutting property 50mm X Distance100mm X 6kg X 5min No abnormality in the confidentiality test no problem Bracket 11. Leaving property 100 mm X min X 600 N (61.2 kgf) X 5 min No deviation of the bracket and no abnormality in the confidentiality test after the test No leak

City gas hose self-test report (development) 2010. 7. 23 division Test Items Exam conditions City Gas Corporation Standards Test result

Inner rubber

1. Tensile strength MIn. 14.7 KN / m 16.8KN / m
2. Gas resistance
-20 ℃ X LPG X 24hrs 1.2 40 ℃ X LPG X 24hrs Volume change rate -3 ~ 10% 1.5 -25 ℃ X Air X 24hrs 0.8 3. air aging 70 ℃ X 48hrs Tensile Strength: MAX.20% 5.3% Floor Total Peel strength Min.3.1Kg / Inch 4.6Kg / Inch








hose



1.pressure resistance 3Mpa 30.6kgf / ㎠ No abnormality in the bracket and hose cross section No leak 2. Bursting MIn. 4Mpa
40.8kgf / ㎠ 135.5Kgf / ㎠ 3. Confidentiality 0.2Mpa 2kgf / ㎠ No leakage of air No leak 4. Minimum bending (high temperature) 120 ± 2 ℃ X 48hrs X Minimum Bend (70mm) No cracks and swelling No cracks and swelling 5. Minimum bending (low temperature) 0.5m X -25 ± 3 ℃ X 24hrs X 3/2 Point 45 Degree Bend No crack or damage No cracks or breakage 6. Ozone Resistance 40 ± 2 ℃ X 50pphm X 96hrs X Minimum Bend (70mm) No crack or damage No crack or damage 7. Gas permeability 0.9m X 35 ± 0.5 ℃ X 98% Propane X 24 ~ 30hrs Max.5ml / 1hrs 1.5ml / 1hrs 8. Flame retardant Burner Use No flame burning for more than 5 seconds 0 sec 9. Cutting property 50mm X Distance100mm X 6kg X 5min No abnormality in the confidentiality test no problem
Bracket 11. Leaving property 100 mm X min X 600 N (61.2 kgf) X 5 min No deviation of the bracket and no abnormality in the confidentiality test after the test No leak

As described above, it can be seen that the present invention exhibited significantly better results (rupture resistance, flame resistance, flame retardancy, airtightness) than the standard of city gas high pressure hose for city gas corporation.

Hereinafter, the present invention will be described with reference to the drawings.

As shown in FIG. 1, the structure of the present invention is a high pressure hose for city gas, which is laminated in the order of an inner rubber layer (1), a wire reinforcing layer (2), an outer rubber layer (3), and an outer urethane outer layer (4). have.

Rubber inner layer (1), wire reinforcing layer (2), rubber outer layer (3), urethane outer layer (4).

Claims (1)

A method of manufacturing a high pressure hose for city gas,
Nitrile butadiene (NBR) rubber is introduced into the feeder of the rubber high pressure hose manufacturing extruder and extruded into a tubular shape to form a tubular rubber inner layer (1)-(extrusion outer diameter 11.9mm) whose inner diameter is 9.5 mm, and then to the front side. Transport it,
Wire reinforcing layer installed on the front side is braided to the outside of the rubber inner layer (1) to form the wire reinforcing layer (2)-(braiding outer diameter 13.1mm) by braiding 2-5 strands of steel wire having a diameter of 0.25 to 0.30mm. And then
It is transferred to the feeder device of the extruder for manufacturing a rubber high pressure hose installed at the front side and selected from chloro polyethylene (CPE), chloroprene (CR), styrene butadiene (SBR) and ethylene propylene (EPDM) on the outside of the wire reinforcement layer (2). After coating (coating) with synthetic rubber, laminating the rubber outer layer (3)-(cover outer diameter 15.5mm), and then going through general processes such as filamentation, vulcanization, degassing, and extraction. After transferring to the coating process,
When transported to the rim installed on the rear to maintain a tensile force of 20kgf / ㎠ or more to tension the manufactured tube, at this time, the outer diameter of the urethane by coating (coating) the urethane resin in the state that the product outer diameter of the tube is stretched 0.5mm ~ 1mm ( 4)-(Coating outside diameter 16.5mm) is formed, and then the tension force applied to the hose is lost when passing through the intake machine (caterpillar) installed on the front side, so the stretched hose is restored to its original state and the stretched outer diameter returns to its original position. A method of manufacturing a high pressure hose for a city gas, characterized in that the rubber outer layer (3) and the urethane outer layer (4) to be in close contact with each other.

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