WO2009110707A2

WO2009110707A2 - Double layer elbow production method and apparatus

Info

Publication number: WO2009110707A2
Application number: PCT/KR2009/000994
Authority: WO
Inventors: 최태룡
Original assignee: 신일중공업 주식회사
Priority date: 2008-03-03
Filing date: 2009-03-02
Publication date: 2009-09-11
Also published as: WO2009110707A3

Abstract

A double layer elbow production apparatus according to the invention is characterized by comprising: a main body having a receptacle defined therein; a pressing guide, which is disposed inside the receptacle of the main body and has a plurality of pressure pieces arranged along a circumference direction, the pressure pieces being formed in a way to make a synchronized sliding movement with neighbouring pressure pieces, respectively, so as to approach one another in a radiation direction; a plurality of springs, which is installed between the pressure pieces of the pressing guide to provide the elastic force in a direction in which the pressure pieces move away from one another; a split mould, which has a plurality of mould elements, each being disposed on a radially outer side of a respective one of the pressure pieces of the pressing guide, inner circumferential surfaces of the mould elements forming the peripheral geometry of an elbow tube bent on a curved path as the pressure pieces of the pressing guide move forwards in the radial direction to bring the mould elements into contact with one another; and a cylinder, which is installed inside the receptacle of the main body and has a cylinder rod for applying an external force to at least one of the pressure pieces of the pressing guide by making a forward/backward movement with respect to the pressing guide. Further, the double layer elbow production method according to the invention is characterized by comprising the steps of: inserting into an outer elbow tube an inner elbow tube made out of heat-treated, wear-resistant steel; and pressurizing the outer elbow tube being bent on a curved path by a plurality of mould elements arranged along a circumference direction so as to adhere the inner circumferential surface of the outer elbow tube onto the outer circumferential surface of the inner elbow tube.

Description

Double pipe elbow manufacturing device and double pipe elbow manufacturing method

The present invention relates to a method and apparatus for manufacturing a double tube elbow, and more particularly, to an inner elbow having a plurality of molds by inserting an inner elbow having abrasion resistance into a hollow outer elbow, and then bending the outer elbow into a plurality of molds. A method and apparatus for producing a double tube elbow quickly and efficiently by pressing against.

In the concrete pump car, a double pipe having abrasion resistance is used to transfer the concrete to be conveyed. Double tube is divided into straight tube and elbow tube. Straight pipes transport concrete in a straight line, and elbows are bent at a certain angle so as to redirect the concrete to be transported and used to connect between vertical pipes.

The present invention relates to a double tube elbow bent at an angle. The conventional double pipe elbow includes an outer elbow pipe bent at a predetermined angle, and an inner elbow pipe inserted into the inner circumferential surface of the outer elbow pipe and having an abrasion resistance that is heat-treated so that it is not easily worn by the pressed concrete. In addition, flanges are welded to both ends of the outer elbow pipe so as to connect and install another transfer pipe.

Conventional methods for producing double tube elbows having the above configuration are known as follows. The first manufacturing method is to produce a double tube elbow by manufacturing the outer elbow tube in a symmetrical form divided up and down by a press, and welding the outer elbow tubes to each other with the inner elbow tube disposed therebetween. In the second manufacturing method, instead of joining the upper and lower outer elbows by welding, flanges are formed on the joining surfaces of the divided outer elbows, holes are formed in the flanges, and the flanges are fastened to each other by bolts and nuts. To produce. In this way, in order to weld the outer elbows divided up and down or fasten with bolts and nuts, the welded or bolts are tightened while the divided outer elbows are pressed to closely contact each other.

This method requires a separate pressurization device. In particular, the method of manufacturing the double tube elbow by welding has a problem that wear resistance is lowered because the inner tube is heated to deform the tissue during welding. In addition, since the welding work is cumbersome, there is a problem that the productivity is low, and the production quality is determined according to the skill of the operator.

In the method of manufacturing a double pipe elbow by fastening with a bolt and a nut, it is important to work by tightening the bolt and the nut uniformly so that the divided outer elbow tube closely adheres to the inner elbow tube. However, when using the double pipe elbow manufactured in this way for a long time, the bolt is loosened. When the close contact between the outer elbow and the inner elbow is released there is a problem that is easily broken in the impact. In addition, it is difficult to fasten so that the outer elbow is in close contact with the inner elbow with a plurality of bolts and nuts at a uniform pressure, there is also a problem that takes a lot of assembly time.

The conventional double pipe elbow manufacturing method having such a problem has low reliability of the manufactured product and low productivity due to a complicated manufacturing process. In addition, the double pipe elbow manufactured by the conventional method has a problem that the appearance is bad and the volume of the product is bad because the weld line or bolt and nut is exposed to the outside of the outer elbow pipe.

The present invention is to solve the above problems, it is an object of the present invention to provide a method for producing a double pipe elbow without dividing the outer elbow pipe.

In addition, an object of the present invention is to provide a method for producing a double-tube elbow that can improve the reliability of the product by not welding by splitting the outer elbow pipe or bolted.

Apparatus for producing a double pipe elbow according to the present invention includes a main body with a receiving portion; A compression guide having a plurality of pressing pieces arranged in the circumferential direction, the pressing pieces are formed so as to be in close proximity to each other in the radial direction in synchronization with each other while sliding with the adjacent pressing pieces, the pressing guide disposed inside the receiving portion of the main body ; A plurality of springs provided between the pressing pieces of the crimping guide to provide elastic force in a direction away from each pressing piece; And a plurality of mold elements installed on radially outer surfaces of the pressing pieces of the pressing guide, wherein the pressing pieces of the pressing guide are radially advanced so that the inner circumferential surfaces of the mold elements are in a curved path when the mold elements are in contact with each other. Split molds to be the outer peripheral shape of the bent elbow; And a cylinder rod which moves forward and backward with respect to the crimping guide to apply an external force to at least one of the pressing pieces of the crimping guide, and is installed inside the receiving portion of the main body.

In addition, the manufacturing method of the double pipe elbow according to the present invention comprises the steps of: inserting the inner elbow tube made of heat-resistant wear-resistant steel inside the outer elbow pipe; And pressing the outer elbow tube bent in a curved path with a plurality of mold elements arranged in the circumferential direction so that the inner circumferential surface of the outer elbow tube is brought into close contact with the outer circumferential surface of the inner elbow tube.

According to the present invention, since the integral outer elbow is pressed and molded into the inner elbow, the inner elbow and the outer elbow can be brought into close contact with each other. Therefore, the defect rate is reduced, and it is possible to provide a double tube elbow having a clean and beautiful appearance. In addition, there is an effect that the production process of the double pipe elbow is simple and easy to improve the productivity.

In addition, according to the present invention, the inner elbow is not damaged by heat, thereby increasing durability and decreasing a defective rate. In addition, even if used for a long time, the close contact between the inner elbow and the outer elbow tube is not alleviated, so that it is prevented from being damaged by an external impact to increase durability. The increased durability allows the user to reduce the cost of replacing the double tube elbow.

1 is a perspective view of one embodiment of a compression manufacturing apparatus of a double pipe elbow according to the present invention.

2 is a cross-sectional view taken along the line A-A of FIG.

3 is a cross-sectional view taken along the line B-B in FIG.

4 is a cross-sectional view for explaining an operating state of the compression production apparatus of the double tube elbow shown in FIG.

5 (a) to 5 (f) are views for explaining a method for producing a double tube elbow using the compression production apparatus of the double tube elbow shown in FIG.

6 is a perspective view of the double tube elbow of the first embodiment produced by the manufacturing method of FIG.

FIG. 7 is a cross-sectional view of the double tube elbow of the second embodiment produced by the manufacturing method of FIG. 5.

300 Double pipe elbow manufacturing unit 310 main body

320 cylinder 321 cylinder rod

330 Crimping Guide 331 ~ 338 1st pressure piece ~ 8th pressure piece

340 Split Mold 341 ~ 348 Mold Element

350 Guide 351 Stopper

S spring b1, b2 first and second bolt

200,200 'Double Pipe Elbow 210 Inside Elbow Pipe

220

Outer elbow

230, 240 flange

250 Reinforcement Pipe W Weld

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

1 is a perspective view of one embodiment of the compression manufacturing apparatus of a double tube elbow according to the present invention, Figure 2 is a cross-sectional view taken along the line AA of Figure 1, Figure 3 is a cross-sectional view taken along the line BB of Figure 1, Figure 4 It is sectional drawing explaining the operation state of the crimp manufacturing apparatus of a double pipe elbow.

The double pipe elbow manufacturing apparatus 300 of the present embodiment includes a main body 310, a cylinder 320, a crimping guide 330, and a split mold 340.

The main body 310 includes a receiving portion 311 penetrated in the width direction. The cylinder 320, the crimping guide 330, and the split mold 340 are installed in the receiving portion 311 of the main body 310.

The pressing guide 330 includes a plurality of pressing pieces 331 to 338 arranged in the circumferential direction. The pressing pieces 331 to 338 are formed to be in close proximity to each other in synchronization with the adjacent pressing pieces 331 to 338 while sliding.

More specifically, referring to FIG. 2, the first pressing piece 331 is installed on the upper surface of the main body 310 accommodating part 311. The fifth pressing piece 335 is installed to face the first pressing piece 331. Third and seventh

pressing pieces

333 and 337 are installed to slide along both inclined surfaces of the first and fifth

pressing pieces

331 and 335. The second pressing piece 332 is provided between the first and third

pressing pieces

331 and 333, and the fourth pressing piece 334 is provided between the third and fifth

pressing pieces

333 and 335. The sixth pressing piece 336 is provided between the fifth and seventh

pressing pieces

335 and 337, and the eighth pressing piece 338 is provided between the seventh and first

pressing pieces

337 and 331.

When the fifth pressing piece 335 is pushed upward by applying a force, the third and seventh

pressing pieces

333 and 337 provided on both sides of the fifth pressing piece 335 are inclined on both sides of the first and fifth

pressing pieces

331 and 335. Sliding inward direction along the approach to each other. At the same time, the second and fourth

pressing pieces

332 and 334 and the sixth and eighth

pressing pieces

336 and 338 move along the inclined surface in contact with each other.

As described above, it is preferable that the first to eighth pressing pieces 331 to 338 have an inclined surface so as to slide smoothly with each other when the first to eighth pressing pieces 331 to 338 are synchronous with each other.

Springs S are respectively installed between the pressing pieces 331 to 338 of the crimping guide 330. Springs (S) are installed to provide an elastic force in the direction in which each of the pressing pieces (331 ~ 338) away from each other. When the force is removed from the pressing pieces 331 ˜ 338 in the state moved to approach each other in the radial direction, the pressing pieces 331 ˜ 338 move in a direction away from each other by the elastic force of the spring S. Therefore, by the action of the spring (S) to the inside of the pressing pieces (331 ~ 338) to retract or spread outwards is made stable and uniform.

On the other hand, the pressing pieces 331 to 338 are assembled in such a way that the inclined surfaces in contact with each other in the form of uneven grooves so that the pressing pieces 331 to 338 slide inwardly or slide out without being separated from each other. It is desirable to be. In addition, in order to guide the fifth pressing piece 335 to be stably forward / backward, it is preferable that the inner surface of the receiving portion 311 and the outer surface of the fifth pressing piece 335 are also formed to engage with each other in an uneven groove shape.

In this embodiment, the case of having eight pressing pieces 331 to 338 of the crimping guide 330 has been described as an example. However, the present invention is not limited thereto, and fewer or more pressing pieces may be used if necessary. It is also possible to provide.

The division mold 340 includes eight division molds 341 to 348. Each mold element 341 to 348 is installed on the radially outer surface of each of the pressing pieces 331 to 338. When the pressing pieces 331 to 338 of the crimping guide 330 are advanced in the radial direction and the mold elements 341 to 348 are in contact with each other, the inner circumferential surfaces of the mold elements 341 to 348 are bent in a double pipe elbow. It forms the outer peripheral shape of 200. The mold elements 341 to 348 of the present embodiment form the outer circumferential surface shape of the double tube elbow 200 bisected in the longitudinal direction of the double tube elbow 200 bent at 90 °. In this embodiment, since the double pipe elbow 200 is a curved path having a circular cross section, when the inner peripheral surface is connected to the mold elements 341 to 348, the double pipe elbow 200 is formed as a curved path having a circular cross section.

2 and 3, the mold elements 341 to 348 of the split mold 340 may be easily coupled and separated from the first to eighth pressing pieces 331 to 338 of the crimping guide 330. Is installed. A radially outer peripheral surface of each mold element 341 to 348 is installed such that the first bolt b1 protrudes. Each pressing piece 331 ˜ 338 is provided with a groove 339 for receiving the first bolt b1. The second bolt b2 is screwed to each of the pressure pieces 331 to 338 while the first bolt b1 is fitted into the groove 339 of each of the pressure pieces 331 to 338. ), The mold elements 341 to 348 are coupled to the pressing pieces 331 to 338.

When the split mold 340 is damaged or the split mold 340 is replaced to manufacture another double pipe elbow, when the second bolt b2 is loosened, the split mold 340 is separated from the crimping guide 330, thereby easily replacing. Do.

On the other hand, the fifth pressing piece 335 is provided with a guide 350 for supporting the double pipe elbow 200. The guide 350 is provided with a stopper 351 for supporting the end of the double pipe elbow 200.

The cylinder 320 is installed inside the receiving portion 311 of the main body 310. The cylinder 320 includes a cylinder rod 321 that exerts an external force on the fifth pressing piece 335 of the crimping guide 330 by moving forward and backward with respect to the crimping guide 330. When the cylinder rod 321 moves forward with respect to the crimping guide 330, the first to eighth pressing pieces 331 to 338 retract inward. On the contrary, when the advanced cylinder rod 321 moves backward, the first to eighth pressing pieces 331 to 338 open outward.

Hereinafter, the manufacturing method of the double pipe elbow which concerns on this invention using the said double pipe elbow manufacturing apparatus apparatus 300 is demonstrated.

5 (a) to 5 (f) is a view for explaining a manufacturing method of the double pipe elbow using the compression production apparatus of the double pipe elbow according to the present invention, Figure 6 is a manufacturing method by the manufacturing method of FIG. A perspective view of a double tube elbow of one embodiment.

First, as shown in Fig. 5 (a), the inner elbow tube 220 made of weldable steel and the inner elbow tube made of heat-resistant wear-resistant steel and having an outer diameter smaller than the inner diameter of the outer elbow tube 220 ( Prepare 210). In addition, a pair of cylindrical flanges 230 and a reinforcement pipe 250 made of weldable steel are prepared, respectively.

Next, as shown in FIG. 5 (b), an insertion step of gradually pushing the inner elbow 210 bent at 90 ° to the hollow outer elbow 220 is bent at 90 °. As such, when the inner elbow 210 is pushed into the outer elbow 220, a minimum gap d exists between the inner diameter of the outer elbow 220 and the outer diameter of the inner elbow 210 for smooth insertion. do.

Next, the outer elbow tube 220 in which the inner elbow tube 210 is inserted as shown in FIG. 5 (d) is disposed in the double pipe elbow manufacturing apparatus 300 as shown in FIG. 5 (c). That is, the split mold 340 of the double-pipe elbow manufacturing apparatus 300 according to the present invention is inserted in order to squeeze a half halves with respect to the longitudinal direction of the double-pipe elbow 200. At this time, one side of the double pipe elbow 200 is located in the split mold 340, the other half is supported by the guide 350. The double pipe elbow 200 is supported by the stopper 351 formed at the end of the guide 350 so as not to be pushed.

Next, pressing the outer elbow tube 220 with a plurality of mold elements 341 to 348 arranged in the circumferential direction to press the inner circumferential surface of the outer elbow tube 220 against the outer circumferential surface of the inner elbow tube 210. To perform. As the cylinder rod 321 moves upward, the fifth pressing piece 335 of the crimping guide 330 is pressed upward. At this time, the third and seventh

pressing pieces

333 and 337 move inwards along the inclined surfaces of the first and fifth

pressing pieces

331 and 335, and at the same time, the second and fourth

pressing pieces

332 and 334 and the sixth and eighth pressing pieces.

Pieces

336 and 338 also move inward along the inclined surfaces that are in contact, respectively. As the crimping guide 330 is retracted inward, the first and eighth pieces 341 to 348 of the divided molds 340 respectively installed on the first to eighth pressing pieces 331 to 338 are also moved and the outer elbow 220 is moved. Evenly compress the bisected half of). First, as shown in FIG. 5 (d), a first compression step is performed to bring one half of the outer elbow tube 220 into close contact with the inner elbow tube 210, and then, as illustrated in FIG. 5 (e). As described above, a second compression step of pressing the other half of the outer elbow tube 220 to the inner elbow tube 210 is performed. When the outer compression tube 220 is continuously compressed, the distance elbow between the outer elbow pipe 220 and the inner elbow pipe 210 is compressed and the outer elbow pipe plastically deformed on the outer circumferential surface of the inner elbow pipe 210 ( The inner circumferential surface of 220 is in close contact with each other.

When the first pressing step or the second pressing step is completed, and the cylinder rod 321 is retracted by the elastic force of the spring (S), the distance between the pressing pieces (331 ~ 348) is also separated by the split mold 340 Spread outwards As described above, the double pipe is removed from the double pipe elbow manufacturing apparatus 300 in a state that is as wide as possible.

Next, as shown in FIG. 5 (f), the flange 230 is installed on both ends of the separated double pipe, and then the reinforcement pipe 250 which is a steel having a separate heat-treated abrasion resistance on the inner circumferential surface of each flange 220. ) And install it by force fitting. At this time, the flange 220 has a tapered portion 231 whose inner diameter increases with distance from the outer elbow tube 220. In addition, the reinforcement pipe 250 is formed so that its outer peripheral surface is in close contact with the inner peripheral surface of the flange 230, the tapered portion 251 corresponding to the tapered portion 231 of the flange 230 is formed on the outer surface.

In order to prevent the flanges 230 respectively installed at both ends of the double pipe from being separated, the flange 230 and the outer elbow tube 220 are fillet welded to each other (W).

In addition, the inner diameter of the reinforcement pipe 250 is preferably the same as the inner diameter of the inner elbow pipe 210 in order to prevent easy wear by the concrete being pushed.

In addition, the outer surface in the pipe direction of the reinforcement pipe 250 and the same outer surface of the flange 230 may be positioned at substantially the same plane. When configured in this way, the connection of the transfer pipe is easy, there is an advantage that can prevent the portion damaged by the concrete to be reinforced by the reinforcement pipe 250 is further protruded or short.

The double pipe elbow 200 ′ of the second embodiment manufactured by the present invention is manufactured by the double pipe elbow manufacturing apparatus 300 from the step of inserting the inner elbow pipe 210 as in the double pipe elbow 200 of the first embodiment. Since the steps of separating the compressed double pipe from the manufacturing apparatus 300 are the same, the following procedure will be described below.

In order to easily weld the flanges 240 to both ends of the separated double pipe, it is preferable that both ends of the inner elbow pipe 210 protrude more than both ends of the outer elbow pipe 220. In addition, the inner circumferential surface of each flange 240 to be welded has a large diameter portion 241 having a diameter substantially the same as the outer circumferential surface of the outer elbow tube 220, and a diameter substantially the same as the outer circumferential surface of the inner elbow tube 210. The small diameter portion 242 is formed. Fillet welding (W) is applied to the end of the flange 240 and the outer circumferential surface of the outer elbow tube 220 so that the flanges 240 respectively installed at both ends of the double pipe are not separated.

When welding the flange 240, it is preferable that the lateral outer surface of the inner elbow 210 and the same lateral outer surface of the flange 240 are located at substantially the same plane. When configured in this way, it is easy to connect the transfer pipe, it is possible to effectively prevent the inner elbow 210 is damaged by the pressurized concrete.

The double pipe elbows 200 and 200 'produced by the manufacturing method as described above are easy to manufacture and can be manufactured quickly, thereby improving productivity.

Although the present invention has been described as an embodiment for a 90 ° double tube elbow, the present invention is not limited thereto, and a double tube elbow of various angles may be manufactured. As described above, by selectively replacing the divided mold according to the angle of the double pipe elbow to produce the double pipe elbow of various angles, it is possible to manufacture a double pipe elbow of various shapes by a single pipe elbow manufacturing apparatus.

In addition, the method of manufacturing a double pipe elbow by dividing the double pipe elbow into two halves by the first compression step and the second compression step has been described as an example, but instead of dividing it into half, the double elbow can be crimped as a whole. You can also make. In this case, the double-pipe elbow manufacturing apparatus having a split mold capable of processing the entire outer circumferential shape of the double-tube elbow is not used without using the split mold configured to form the outer circumferential shape of the double-tube elbow divided into two parts as described above. The method can be carried out.

Claims

A main body having a receiving portion formed therein;

A compression guide having a plurality of pressing pieces arranged in the circumferential direction, the pressing pieces are formed so as to be in close proximity to each other in the radial direction in synchronization with each other while sliding with the adjacent pressing pieces, the pressing guide disposed inside the receiving portion of the main body ;

A plurality of springs provided between the pressing pieces of the crimping guide to provide elastic force in a direction away from each pressing piece;

And a plurality of mold elements installed on radially outer surfaces of the pressing pieces of the pressing guide, wherein the pressing pieces of the pressing guide are radially advanced so that the inner circumferential surfaces of the mold elements are in a curved path when the mold elements are in contact with each other. A split mold that becomes an outer circumferential shape of the bent double pipe elbow; And

Double cylinder elbow manufacturing apparatus comprising a; a cylinder rod having a cylinder rod for applying an external force to at least one of the pressing pieces of the crimping guide to move forward and backward with respect to the crimping guide; .
The method of claim 1,

The radially inner circumferential surfaces of the mold elements of the divided mold are connected to each other to form an outer circumferential shape of the double tube elbow bisected in the longitudinal direction.
The method according to claim 1 or 2,

The radially inner circumferential surface of the mold elements of the divided mold is connected to each other is formed in a double pipe elbow manufacturing apparatus characterized in that formed in a curved path having a circular cross section.
The method of claim 3,

On the radially outer peripheral surface of each of the mold elements is installed so that the first bolt protrudes,

Each of the pressing pieces is formed with a groove for receiving the first bolt,

And a second bolt screwed to each of the pressing pieces respectively presses the first bolt received in the groove so that each mold element is coupled to each of the pressing pieces.
The method of claim 4, wherein

The pressing pieces of the crimping guide is eight,

Double mold elbow manufacturing apparatus, characterized in that the eight mold elements of the divided mold.
The method of claim 3,

Double pipe elbow manufacturing apparatus, characterized in that the guide for supporting the double pipe elbow is installed on at least one of the pressure pieces.
The method of claim 6,

Double guide elbow production apparatus, characterized in that the stopper is installed on the guide supporting the end of the double pipe elbow.
Inserting an inner elbow formed of a heat-resistant wear resistant steel into the inner elbow; And

Pressurizing the outer elbow pipe bent in a curved path with a plurality of mold elements arranged in the circumferential direction by pressing the inner circumferential surface of the outer elbow pipe to be in close contact with the outer circumferential surface of the inner elbow pipe; manufacturing of a double pipe elbow Way.
The method of claim 8,

The pressing step may include a first pressing step of bringing the longitudinal half of the outer elbow into close contact with the inner elbow, and a second pressing step of bringing the other half of the outer elbow into close contact with the inner elbow. Method for producing a double tube elbow, characterized in that.
The method according to claim 8 or 9,

The pressing step, the manufacturing method of the double pipe elbow, characterized in that performed in a state in which the outer elbow is disposed on the support portion installed on at least one of the mold elements.
The method of claim 8 or 9,

And welding flanges to both ends of the outer elbow pipe, respectively.
The method of claim 11,

A method of manufacturing a double pipe elbow, wherein an outer surface in the pipe direction at both ends of the inner elbow tube and an outer surface in the same direction of the flange are substantially in the same plane.
The method of claim 11,

The flange is a manufacturing method of a double pipe elbow, characterized in that it comprises a tapered portion whose inner diameter increases as the distance away from the outer elbow pipe.
The method of claim 13,

A reinforcement pipe inserted into the flange and having an outer circumferential surface thereof in close contact with the inner circumferential surface of the flange and having a tapered portion corresponding to the tapered portion of the flange;

The reinforcement pipe is a method of producing a double-pipe elbow, characterized in that the heat-resistant wear-resistant steel.
The method of claim 14,

The inner diameter of the reinforcing pipe is a method of producing a double pipe elbow, characterized in that substantially the same as the inner diameter of the inner elbow pipe.
The method of claim 15,

A method for producing a double pipe elbow, characterized in that the pipe outer side surface of the reinforcing pipe and the same direction outer surface of the flange are substantially in the same plane.