WO2018026022A1

WO2018026022A1 - Method of molding metal bellows tube provided with liquid quantity adjustment mechanism, and molding device for same

Info

Publication number: WO2018026022A1
Application number: PCT/JP2017/028503
Authority: WO
Inventors: 佐々木　勇; 鈴木　啓司
Original assignee: 株式会社昭和螺旋管製作所
Priority date: 2016-08-05
Filing date: 2017-08-04
Publication date: 2018-02-08

Abstract

[Problem] In hydraulic forming of bellows, to prevent an increase in the size and complexity of a device using a simple construction, and to make it possible to reduce the quantity of water and reduce power consumption. [Solution] Two ends of a hollow starting material pipe (P) are hermetically sealed by means of a fixed die (12) and a movable die to form a space (S) in a hollow portion of the starting material pipe (P). A divided die (14) is disposed on the outer periphery of the starting material pipe (P) in order to mold the bellows, and a core (17) of a liquid quantity adjustment mechanism (15) is inserted into the space (S) in the starting material pipe (P) with freedom to move forward or backward, to form a space that is different after the core (17) has been inserted compared with the space before the core (17) has been inserted, and bellows molding liquid (W) is introduced via a liquid feed hole (17a) in the core (17) into the sealed space (S1) having the smaller volume after said insertion.

Description

Metal bellows tube forming method with liquid amount adjusting mechanism, and apparatus for forming the same

Technical field 1

In this invention, when a bellows is formed on the outer periphery of a base pipe by bulging, the space formed by the core metal and the base pipe is reduced in volume with a small volume by closely contacting the molding die on one side when the insertion of the core metal is completed. The present invention relates to a bellows molding method and a bellows molding apparatus that can be changed to a space portion and prevent an increase in size and complexity of the apparatus with a simple structure, and that can reduce the amount of water and power consumption.

Conventionally, as shown in FIG. 4, a metal bellows molding apparatus for bulge processing includes a mold body 1 having a pair of

split molds

2 and 2 as a set, and a half hole 2a of both split

molds

2 and 2. 2a, the outer circumference of the raw pipe P is clamped and restrained in the radial direction, and a plurality of divided

molds

2, 2,... (B) and (c), both ends of the raw pipe P are sealed with

end cap members

6 and 6, and the internal pressure of the raw pipe P is increased by a liquid inflow device (not shown). The U-shaped convex portions 2 b of the

split holes

2 a and 2 a are fitted and moved in the axial direction to form a corrugated bellows (bellows portion).
In addition, 3 ... is a support shaft hole opened at the four corners of the mold body 1, and a support shaft shaft 4 ... penetrating through the support shaft hole 3 ... and a clamp member 5 arranged at the upper part. This prevents the tube axis from collapsing in the axial direction.

In addition to the above-described split mold, there is a split mold by a combination of an inner mold and an outer mold, for example, Patent Document 1 as shown in FIG.
In the

split molds

2 and 2, the split mold is constituted by the

inner molds

6 and 6 and the

outer molds

7 and 7, and the

inner mold shafts

6 b and 6 b and the outer mold shaft holes through which the inner

mold shaft holes

6 a and 6 a are inserted. 7a and 7a are supported by the

outer mold shafts

7b and 7b, and the

inner molds

6 and 6 and the

outer molds

7 and 7 are combined to be slidable and rotatable. The inner mold 6 is rotated between the combined position where the

split surfaces

6b and 6b of the

inner molds

6 and 6 are aligned with the

split surfaces

7b and 7b of the outer molds 7 and the molding position where they are not aligned. It is of the method.
Thereby, the acting direction of the resultant force between the

inner dies

6, 6 and the

outer dies

7, 7 can prevent the separation of the

inner dies

6, 6 by the rigidity of the

outer dies

7, 7.

By the way, as a method of forming a metal bellows tube, (1) roll forming method, (2) hydraulic forming method (bulge forming method), (3) welding method, (4) electrodeposition method, etc. are known. However, in bulge forming, it is an essential requirement to prevent the mold body from tilting in the axial direction, and various technical means are adopted depending on the purpose of the product used based on that technology. The
Therefore, Patent Document 2 proposes to provide an inexpensive tubular structure by manufacturing a large-diameter bellows tube by hydraulic forming without causing buckling or the like.
In addition, as shown in FIG. 6, in Patent Document 3, when forming a bellows by hydraulic forming using a straight tubular element tube, the apparatus is made compact and the processing force required for forming is reduced, Bellows molding is provided that allows for a stable seal.

For this reason, in Patent Document 3, an expansion / contraction core 10 composed of a piston 8 and a cylinder 9 is interposed in a raw tube P for bellows molding, and when the piston 8 operates, the hydraulic chamber 10a inside the expansion / contraction core 10 is located. The volume is reduced and the pressure acting on the inside is increased, the volume of the hydraulic chamber 10a formed between the element P and the volume is reduced, and the pressure acting on the inside of the element P is increased and the liquid is increased. The inside of the pressure chamber S is adjusted to be constant.

Japanese Patent Laid-Open No. 10-80729 JP-A-10-277660 JP 09-239453 A

However, although what is shown in Patent Document 2 is a technique of hydroforming a bellows tube, it is not formed by adjusting a space formed between a base tube and a cored bar.
In addition, what is shown in Patent Document 3 is a hydraulic pressure formed between a base tube and a device for compacting the apparatus, reducing a processing force necessary for molding, and enabling a stable seal. Although it has been proposed to reduce the volume of the chamber, the expansion and contraction core consisting of the piston and cylinder is interposed in the raw tube, and the structure itself has become complicated, so it has not been a compact device. .

The applicant of the present application has conducted extensive research in view of such circumstances, and has completed the present invention in order to achieve a technique for preventing an increase in the size of the apparatus with a simple structure.

An object of the present invention is to form a bellows by closely contacting a molding die on one side when the insertion of the cored bar is completed, and changing the space part formed by the cored bar and the raw tube into a space part with a small volume. The simple structure prevents the device from becoming large and complicated, and also enables the reduction of water volume and power consumption.

According to the present invention, as a method for forming a metal bellows tube having a liquid amount adjusting mechanism, both ends of a hollow shell are sealed with a fixed mold and a movable mold as described in claim 1, The hollow part is a space part, and a bellows forming mechanism in which a split mold for forming a bellows is formed on the outer periphery of the base tube, a cored bar supporting mold for supporting the cored bar, and the cored bar supporting mold can be moved back and forth. And a liquid level adjusting mechanism including a cored bar pressing part that moves the cored bar, and a liquid level adjusting mechanism that includes the cored bar pressing part. While arranging a quantity adjusting mechanism, the cored bar is inserted into the space part of the base tube so as to freely advance and retract, and the space part of the base pipe is a different space part before and after the insertion of the cored bar, For sealed small volume space after insertion is complete The bellows forming liquid is introduced through the liquid feeding hole of the cored bar, and is formed.
According to a second aspect of the present invention, the bellows forming mechanism is characterized in that the liquid amount adjusting mechanism is attached in a replaceable manner.
According to a third aspect of the present invention, the core metal of the bellows forming mechanism is characterized in that the outer diameter can be appropriately changed to a different outer diameter.

Further, as a metal bellows tube forming apparatus provided with a liquid amount adjusting mechanism, both ends of a hollow base tube are sealed with a fixed mold and a movable mold as described in claim 4, and the hollow of the base tube is formed. A bellows forming mechanism in which a split mold for forming a bellows is formed on the outer periphery of the base tube, a core metal support mold for supporting the core metal, and a metal core support mold that can be moved forward and backward. And a liquid level adjusting mechanism composed of a cored bar pressing part that moves the cored bar and a cored bar pressing part. The liquid level adjustment is performed on a movable mold on one side of the bellows molding mechanism. In addition to the arrangement of the mechanism, the cored bar is inserted into the space of the base tube so as to be movable back and forth, and the space of the base tube is a different space before and after the insertion of the cored bar. Against the sealed small volume space at the back, the core Liquid feed holes introduction of bellows molding fluid through, characterized in that the made of.
According to a fourth aspect of the present invention, the space portion after the completion of the insertion of the cored bar is composed of an inner diameter surface of the base tube, an outer diameter surface of the cored bar, the fixed molds, and an inner wall surface of the movable mold. The space portion is formed and sealed, and has a small volume.
According to a fifth aspect of the present invention, the liquid amount adjusting mechanism is attached to the bellows forming mechanism in a replaceable manner.
According to a sixth aspect of the present invention, the liquid amount adjusting mechanism or the core bar of the liquid amount adjusting mechanism is exchanged manually.

According to the present invention, when the insertion of the raw tube is completed, the space between the core metal and the raw tube can be changed to a space with a small volume by being in close contact with the molding die on one side. While preventing an increase in size and d complexity, it is possible to reduce the amount of water and power consumption.
In addition, since the liquid amount adjusting mechanism is replaceable with the bellows forming mechanism, the simple structure can prevent the apparatus from becoming large and complicated, and can reduce the amount of water and power consumption. .
Therefore, as eco-energy, the amount of water at the time of bellows molding can be reduced, the molding time can be reduced, the power consumption can be reduced, and the total cost can be reduced.

It is a vertical section explanatory view showing a schematic structure of a bellows forming device concerning this invention. FIG. 2 is a cross-sectional view taken along line AA in FIG. FIG. 2 is a longitudinal explanatory view showing the completion of core metal insertion in FIG. It is explanatory drawing which shows the initial state of a liquid quantity adjustment mechanism and a bellows shaping | molding mechanism. It is explanatory drawing which shows the 2nd step of a liquid quantity adjustment mechanism and a bellows shaping | molding mechanism. It is explanatory drawing which shows the 3rd step of a liquid quantity adjustment mechanism and a bellows shaping | molding mechanism. It is explanatory drawing which shows the last step of a liquid quantity adjustment mechanism and a bellows shaping | molding mechanism. Explanatory drawing which shows the bellows shaping | molding by the conventional bulge process. Explanatory drawing which shows the other conventional Example. It is explanatory drawing which shows the other Example of the conventional bellows shaping | molding.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing a bellows forming mechanism 11 and a liquid amount adjusting mechanism 15 constituting the bellows forming apparatus.
The bellows forming mechanism 11 is arranged on the outer periphery of the hollow tube P having a predetermined thickness, the fixed mold 12 and the movable mold 13 which are molding dies for sandwiching both sides of the raw tube P, and the pipe P. And a plurality of divided molds 14. Although the bellows molding is performed by the split molds 14..., The split mold 14 is half-cut in a curved shape on both sides of the lower part, and the bellows molding is performed by the split holes. As is also shown, it is well known in the art and will not be described in detail.
Specifically, the hollow shell P has a predetermined outer diameter, a predetermined inner diameter, a predetermined thickness t, a predetermined length, and a fixed mold that is a molding die. Since both ends are disposed on the mold 12 and the movable mold 13, the hollow portion is a space portion S.
The bellows molding liquid W is conducted to the space S. However, when the bellows molding liquid W is further introduced into the space S, the liquid pressure is increased and the bellows molding liquid W is disposed on the outer periphery of the raw tube P. The bellows is bulged and formed by the divided molds 14. Reference numeral 12 a denotes an air hole provided in the fixed mold 12.

The movable mold 13 is provided with an opening 13a into which a small-diameter support mold body 16c of a core metal support mold 16 to be described later is inserted. The bellows forming mechanism 11 is integrated with the cored bar supporting die 16 by the small diameter supporting die main body 16c inserted into the opening hole 13a. In addition, the divided molds 14 are arranged in a row in the tube axis direction as in the prior art, and are moved in the tube axis direction by a driving device (not shown) and fitted into the U-shaped convex part of the half hole. To form a corrugated bellows.

On the other hand, the liquid amount adjusting mechanism 15 includes a cored bar support die 16, a cored bar 17 that is inserted into the cored bar supporting mold 16 so as to be able to advance and retract, and a core that moves the cored bar 17 toward and away from the bellows forming mechanism 11. It is comprised by the gold | metal pushing part 18. FIG. The core metal support die 16 is disposed on the movable die 13 side of the bellows forming mechanism 11, and includes a support die main body 16a, a step portion 16b, and a small-diameter support die main body 16c via the step portion 16b. The small-diameter support mold main body 16c is inserted into the opening hole 13a of the movable mold 13, and the support mold main body 16c is fixed to the movable mold 13 through the step portion 16b. The cored bar support die 16 has a cored bar insertion hole 16d.

The cored bar 12 has a hollow liquid feed path 17a having a predetermined length and having a predetermined thickness t. The cored bar 12 is inserted into the cored bar support mold 16 so as to be able to advance and retreat, and is bellows via the liquid feed path 17a. The molding liquid W is poured into the bellows molding hole 17b.
The joint surface between the cored bar support die 16 and the cored bar 12 is slid through an O-ring 18 or an oilless bush (not shown), and can be slidable and liquid leakage prevented. The O-ring 18 and the oilless bush are appropriately used between the support die main body 16c and the opening hole 13a of the movable die 13, and are made watertight between each other. It can be suitably used as necessary.
In addition, the watertightness between the fixed mold 12 and the movable mold 13 and the raw pipe P is the same, and conventionally known technical means can be appropriately used as necessary.
Further, the tip end side of the support die body 16c of the cored bar support die 16 is formed with a protruding portion or the like protruding toward the raw tube P side so as to ensure the fitting property with the raw tube P and ensure the water tightness. Well-known technical means can be appropriately used as necessary.
20 is a movable nozzle, and 21 is a fixed nozzle.

The bellows forming mechanism 11 and the liquid amount adjusting mechanism 15 can be controlled by the control unit 100. That is, the bellows molding control unit 200 controls the operations of the fixed mold 12, the movable mold 13, the raw pipe P, the divided mold 14.
The liquid amount adjusting unit 300 controls the operations of the cored bar support die 16, the cored bar 17, and the cored bar pushing part 18.
Along with these operations, the control nozzle 100 controls the fixed nozzle 21 and the movable nozzle 21 which are control valves, and finally the core 17 reaches the fixed mold 12 as shown in FIG. The space portion formed by the raw tube P is a narrow space portion which is the raw tube P after the core bar 17 enters from the “normal volume space portion S” which is the space portion S formed by the raw tube P. It is variable to S1, that is, the “small volume space portion S1”.

Next, the bellows molding operation will be described with reference to the schematic diagrams of FIGS.
(1) FIG. 4: Disassembled state of bellows forming mechanism and liquid amount adjusting mechanism The bellows forming mechanism 11 is formed by assembling a fixed mold 12 and a movable mold 13 to a raw tube P to form a space S, The liquid amount adjusting mechanism 15 is disposed opposite to the other.
(2) FIG. 5: Set state of the bellows forming mechanism and the liquid amount adjusting mechanism When the liquid amount adjusting mechanism 15 is assembled to the bellows forming mechanism 11.
The small-diameter support die main body 16c of the core metal support die 16 is inserted into the opening 13a of the movable die 13, and the support die main body 16c is fixed to the movable die 13 via the step portion 16b.
(3) FIG. 6: State of entry of the core bar into the space portion of the base tube The core bar 17 enters the space portion S of the base tube P from the state of FIG. The space S is gradually narrowed by the cored bar 17.
(4) FIG. 7: State when the core is completely inserted The core 12 is further advanced to complete the insertion, and when the insertion is completed, the tip of the core 12 is in close contact with the fixed mold 14 side. At this time, the space portion S is the volume of the space portion S1 having a small volume sealed by the cored bar 17 and the raw tube P.
That is, when the insertion is completed, the space portion has a relationship of S to S> S1, and the volume of the space portion has a relationship of S = V to S1 = V1, and varies to a relationship of different space portions (volumes). .

FIG. 3 shows a state where the mandrel insertion is completed in FIG. 1 (corresponding to FIG. 6).
Thus, when the insertion of the metal core 12 is completed, the tip of the metal core 12 is in close contact with the fixed mold 14 side, and the space S is set when the liquid amount adjusting mechanism 15 is assembled to the bellows forming mechanism 11 ( The space portion S1 having a small volume is changed from the space portion S having a normal volume as shown in FIG.
In this case, when the insertion is completed, the initial space portion S sealed and formed by the raw tube P is a space portion obtained by subtracting the volume due to the insertion of the cored bar 12, that is, a space portion having a small volume. Therefore, the volume when the insertion is completed is V1. Then, the bellows forming liquid W is introduced into the space part S1 having a small volume at the time of completion of the insertion in the core metal 12 through the liquid feeding path 12a of the raw pipe P by a command from the control unit 100. Thereafter, the liquid pressure for the bellows forming liquid W is increased in the space S1, and bellows forming is performed on the outer periphery of the raw tube P along with the axial compression of the split mold 14 disposed on the outer periphery of the raw tube P. It will be.

For this reason, the bellows molding pressure is the same as the conventional one, and even if the molding pressure is constant, the bellows molding pressing force (bellows molding power) can be reduced. That is, since the space portion P of the raw tube P can be easily changed by a simple structure in which the core metal is inserted, the apparatus can be prevented from becoming large and complicated, and the amount of water introduced into the space portion can be prevented. And the power consumption of the apparatus can be reduced.

The space portion S1 is secured by the small-diameter support type main body 16c, and the formation of the space portion S1 is secured by the step portion. Moreover, it may be obtained by a ring-shaped ring or the like, and in any case, it is only necessary to secure a small volume bellows forming space S1 formed when insertion is completed.

And by ensuring the space part S1 with a small volume at the time of completion of insertion in the core metal 12, the bellows forming liquid is introduced into the space part for bellows forming with this small volume, and bellows forming is performed. For this reason, the bellows molding pressure is the same as the conventional one, and even if it is constant, the bellows molding pressing force can be reduced. In other words, since it has a simple structure that only inserts a mandrel, it can prevent the equipment from becoming large and complicated, and it can also reduce the amount of water and power consumption. can do.

Next, a second embodiment is shown.
The second embodiment is substantially the same as the first embodiment, but is particularly effective in bellows molding of a large diameter pipe, for example, an oil plant, a nuclear power plant, or an aircraft / space development plant. That is, the first embodiment is suitable for automated bellows forming of a relatively general-purpose small-diameter pipe, but in the case of a large-diameter pipe, bellows molding suitable for a large plant is often required. . In addition, bellows molding suited to the field is often required rather than automated bellows molding.
For this reason, in particular, the liquid amount adjusting mechanism 11 needs to be replaceable, and the space S can be changed from a normal volume space of the large-diameter tube to a small volume space S1. Even if it is the same, the bellows molding pressing force (bellows molding power) can be reduced, and it is necessary to reduce the amount of water and power consumption.
In addition, what is necessary is just to use conventionally well-known technical means, such as a manual operation and an automatic exchanger, about replacement | exchange of the liquid quantity adjustment mechanism 11, the metal core 12, etc. FIG.

In addition to bent pipes such as water pipes and gas pipes buried in the ground, etc., small metal bellows suitable for automatic control in order to advance flexible pipes in the medical field, chemical field, aviation field, etc. It can be set as the shaping | molding method and its metal bellows shaping | molding apparatus. Conversely, the present invention can also be applied to a metal bellows forming method and a metal bellows forming apparatus as a large diameter pipe adapted to a large plant such as an oil plant, a nuclear power plant or an aircraft / space development plant. Further, the present invention can be applied to processing of any other raw material other than the raw pipe and the raw pipe.

P Element tube S (v) Space portion Sl (v1) Small volume space W Bellows molding liquid 11 Bellows molding mechanism 12 Fixed mold 12a Air hole 13 Movable mold 13b Opening section 14 Split mold 15 Liquid quantity adjusting mechanism 16 Metal core support die 16a Metal core support body 16b Insert body 16c Stepped portion 17 Metal core 17a Liquid feed path 17b Liquid insertion hole 18 Metal core pushing portion 19 O-ring 20 Fixed side nozzle 21 Movable side nozzle 100 Control unit 200 Bellows molding control unit 300 Liquid volume adjustment control unit 400 Water volume control unit

Claims

A bellows in which both ends of a hollow shell are sealed with a fixed mold and a movable mold, a hollow portion of the blank is used as a space, and a split mold is formed on the outer periphery of the blank to form a bellows. A molding mechanism;
Liquid level adjusting mechanism comprising: a cored bar supporting mold for supporting the cored bar, a cored bar inserted into the cored bar supporting mold so as to be able to advance and retract, a cored bar pressing part for moving the cored bar, and a cored bar pressing part And consists of
The liquid amount adjusting mechanism is disposed in a movable mold on one side of the bellows forming mechanism, and the cored bar is inserted into the space of the base tube so as to freely advance and retract, and the space of the base tube is the cored bar. Different space before and after insertion,
Metal having a liquid amount adjusting mechanism formed by introducing a bellows forming liquid into the sealed small volume space after completion of insertion through the liquid feeding hole of the cored bar Bellows tube forming method.
2. The method for forming a metal bellows tube having a liquid amount adjusting mechanism according to claim 1, wherein the bellows forming mechanism is attached to the liquid amount adjusting mechanism in a replaceable manner.
3. The method for forming a metal bellows tube with a liquid amount adjusting mechanism according to claim 1, wherein the core metal of the bellows forming mechanism can be exchanged with a different outer diameter as appropriate.
A bellows in which both ends of a hollow shell are sealed with a fixed mold and a movable mold, a hollow portion of the blank is used as a space, and a split mold is formed on the outer periphery of the blank to form a bellows. A molding mechanism;
Liquid level adjusting mechanism comprising: a cored bar supporting mold for supporting the cored bar, a cored bar inserted into the cored bar supporting mold so as to be able to advance and retract, a cored bar pressing part for moving the cored bar, and a cored bar pressing part And consists of
The liquid amount adjusting mechanism is disposed in a movable mold on one side of the bellows forming mechanism, and the cored bar is inserted into the space of the base tube so as to freely advance and retract, and the space of the base tube is the cored bar. Different space before and after insertion,
A metal bellows pipe provided with a liquid amount adjusting mechanism, wherein a bellows forming liquid is introduced into a sealed small volume space after completion of insertion through the liquid feed hole of the cored bar. Molding equipment.
The space portion after the completion of the insertion of the cored bar is formed of an inner diameter surface of the core tube, an outer diameter surface of the cored bar, the fixed molds and the inner wall surface of the movable mold, and is a sealed small volume space. The apparatus for forming a metal bellows pipe provided with the liquid amount adjusting mechanism according to claim 1,
5. The metal bellows tube forming apparatus having a liquid amount adjusting mechanism according to claim 4, wherein the liquid amount adjusting mechanism is attached to the bellows forming mechanism in a replaceable manner.
6. The metal bellows tube forming apparatus having a liquid amount adjusting mechanism according to claim 5, wherein the liquid amount adjusting mechanism or the metal bar of the liquid amount adjusting mechanism is exchanged manually.