JPH11156473A - Method and equipment for locally increasing thickness of tubular body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for locally increasing the thickness of a tubular body in which the external dimensions of a wall-thickness increased part are uniform, its outer surface is smoothed, and the wall-thickness increased part is fairly thick. SOLUTION: An intended part of a tubular body 1 is heated, an outer die 25 where annular wall-thickness increased parts 27A, 27B are formed is located on an outer surface 1a at the heated part, the compressive force is given in the longitudinal direction of the tubular body at the heated part, and a part of the material at the heated part is press fitted into the wall-thickness increased parts 27A, 27B. The outer surface 2a of the wall-thickness increased part 2 in the heated condition can be trimmed by the wall-thickness increased parts 27A, 27B, and the outer surface of the wall-thickness increased parts can be uniformed in outer dimensions and smoothed. Because the wall-thickness increased parts 27A, 27B are provided with recessed annular ring part forming surfaces 29A, 29B, the ring part can be projected as soon as the wall-thickness increased parts are formed, and the outer surface of the ring part can be trimmed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used, for example, to form a thickened portion at a connecting portion on a side of a column when a column of a steel structure is connected by a beam material. The present invention relates to a method for partially increasing the thickness of a pipe and a facility for partially increasing the thickness of a pipe.

[0002]

2. Description of the Related Art Conventionally, a beam connecting portion on a pillar side cuts a pillar, that is, a round steel pipe or a square steel pipe into a plurality of pieces in a length direction, and performs a beveling process on a cut surface and then a diaphragm. Although the beam penetration method of attachment has been adopted, this method requires a large amount of time and cost for cutting and groove processing, and has problems such as many welding points.

As a method of cutting a round steel pipe or a square steel pipe, for example, as disclosed in Japanese Patent Application Laid-Open No. Hei 7-238636, an inner diaphragm in which a backing metal is tack-welded around both sides is welded inside the steel pipe. After the backing metal on the insertion port side is tack-welded to the inner wall of the steel pipe, the inner wall of the steel pipe and the outer periphery of the inner diaphragm are subjected to elect slug welding using the through holes. A construction method has been proposed, but this method also required welding work.

In order to eliminate the need for a welding operation, it has been proposed to form a thickened portion at a target portion of a metal tube as disclosed in, for example, JP-A-9-76011. In this thickening method, a rectangular tube is set between a fixing device and a compression device, and the rectangular tube is locally heated by a heating device in a state where a longitudinal compressive force is applied to the rectangular tube. The heating portion is moved in the longitudinal direction to form a thickened portion continuously. At that time,
A heat treatment die is set inside the rectangular tube in order to prevent distortion that is likely to occur in the thickened portion.

[0005]

However, according to the above-described thickening method, there is a possibility that the outer dimensions of the formed thickened portion may be uneven, and therefore, the metal pipe is used as a support to connect the beam members. In this case, there is a possibility that a non-uniform gap may be generated between the two and good welding (connection) cannot be performed. Further, the outer surface of the thickened portion becomes wavy (irregular), which may cause a decrease in welding accuracy and strength. In particular, when the thickness of the thickened portion is to be made considerably thicker than the thickness of the metal tube, irregularities in the outer dimensions and a wavy shape on the outer surface appear remarkably.

Therefore, the invention according to claim 1 of the present invention provides a tube portion which can form the thickened portion with uniform outer dimensions and smooth the outer surface, and which can be formed with a considerably thickened portion. The purpose is to provide a method for increasing the thickness.

[0007] The invention according to claims 6 and 7 is the first invention.
It is an object of the present invention to provide a facility for partially increasing the thickness of a tubular body that can suitably realize the method for partially increasing the thickness of a tubular body.

[0008]

In order to achieve the above-mentioned object, according to the present invention, a method for partially increasing the thickness of a tubular body according to the first aspect of the present invention comprises heating a target portion of the tubular body, With the outer mold having an annular thickened part formed on the outer surface of the tube, a compressive force in the longitudinal direction of the tube is applied to the heated part to sequentially increase the thickness of a part of the material of the heated part. It is characterized by being pressed into a part.

Therefore, according to the first aspect of the present invention, the outer surface of the thickened portion in the heated state can be shaped by the thickened molded portion of the outer die, so that the outer surface of the thickened portion can have a uniform outer dimension. And can be smoothed.

According to a second aspect of the present invention, there is provided a method for partially increasing the thickness of a tubular body according to the first aspect, wherein the thickened portion has a concave ring-shaped portion forming surface. It is what it was.

Therefore, according to the second aspect of the present invention, the ring portion can be protruded and formed simultaneously with the formation of the thickened portion.
The outer surface of the ring can be shaped. According to a third aspect of the present invention, there is provided the method for partially increasing the thickness of a pipe body according to the first or second aspect, wherein the outer mold is positioned on the outer surface of the heated location and the inner mold is located on the inner surface of the heated location. It is characterized by positioning a mold.

Therefore, according to the third aspect of the invention, the outer surface and the inner surface of the thickened portion can be shaped simultaneously with the formation of the thickened portion. Further, in the method for partially increasing the thickness of a pipe according to claim 4 of the present invention, in the configuration according to any one of the above-described claims 1 to 3, the target portion of the pipe is opposed to the outer surface of the pipe. The heating is performed by a heating means from the outside and a heating means from the inside facing the inner surface of the tube.

Therefore, according to the fourth aspect of the present invention, the target portion can be heated quickly and sufficiently from both inside and outside. Moreover, the method for partially increasing the thickness of a pipe according to claim 5 of the present invention is characterized in that, in the configuration according to any one of claims 1 to 4, the pipe is a round steel pipe or a square steel pipe. It is.

Therefore, according to the fifth aspect of the present invention, a round steel pipe or a square steel pipe integrally having the thickened portion and the ring portion can be obtained. Further, in the pipe wall thickening equipment according to claim 6 of the present invention, a pair of clamping means capable of freely holding two locations in the longitudinal direction of the pipe with a target location of the pipe inside, Compressing force applying means for applying a longitudinal compressive force to the tube by relatively moving the means toward and away from each other, heating means for heating a target portion of the tube, and a concave annular thickened molding portion. An outer mold which is formed and is capable of freely contacting and separating is provided on the outer surface of the heating portion.

Therefore, according to the invention of claim 6, both sides of the target portion of the tube are clamped by the clamping means, and the target portion is heated by the heating means, and the outer mold is applied on the outer surface of the heated portion. After the contact, the clamp means is moved relatively close to each other to apply a compressive force in the longitudinal direction to the tubular body, so that a thickened portion can be formed at a target location.

According to a seventh aspect of the present invention, there is provided a pipe wall thickening device, comprising: a pipe receiving means for receiving one end of the pipe; A compressing force applying means for applying a compressive force, a heating means for heating a target portion of the tubular body, and an outer mold having a concave annular thickened molded portion formed on the outer surface of the heated portion and capable of contacting and separating. Is provided.

Therefore, according to the invention of claim 7, one end side of the tube is received by the tube receiving means, and a target portion is heated by the heating means, and the outer die is brought into contact with the outer surface of the heated portion. After that, by applying a compressive force applying means to the other end side of the tubular body to apply a longitudinal compressive force to the tubular body, a thickened portion can be formed at a target location.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.

In FIG. 8A, a round steel pipe 1 as an example of a pipe has a thickness of 4.5 mm to 50.0 mm,
SM490A, SM with a diameter of 100mm to 600mm
520B, SS400, SN400B, SN490B and the like are used. In the round steel pipe 1, a certain range in one place (or a plurality of places) in the longitudinal direction A is set as a target thickening place B.

In FIG. 1, a support means 11 capable of freely supporting a round steel pipe 1 is provided in a pipe part thickening facility 10, and the support means 11 allows the round steel pipe 1 to have its longitudinal direction A as a horizontal direction. Supported. The support means 11 is, for example, of a roller conveyor type for supporting the round steel pipe 1 by a group of hourglass rollers 12, and is configured to forcibly move (convey) the round steel pipe 1 in the longitudinal direction A in the forward and reverse directions. Have been.

A pair of clamping means 1 capable of holding two places in the longitudinal direction A of the round steel pipe 1 with the intended thickening point B of the round steel pipe 1 supported by the supporting means 11 as a center.
5 and 16 are provided, and these clamping means 15 and 16 are configured so as to be relatively movable toward and away from each other. That is, the clamping means 15 and 16 are configured to allow the round steel pipe 1 to be inserted, and are configured to be able to clamp the inserted round steel pipe 1 from the outside.

The clamping means 15, 16 are provided, for example, on carts 17, 18, and are movable in the approaching / separating direction by traveling of the carts 17, 18, and the carts 17, 18 move on the floor at that time. It is performed by a cylinder device provided between the side and the traveling motion device mounted. An example of the compressing force applying means 19 for applying the compressive force in the longitudinal direction A to the round steel pipe 1 by moving the clamping means 15 and 16 relatively close to and away from each other by the carriages 17 and 18 and the traveling device is constituted. .

An outer heating means 20 for heating the thickened portion B of the round steel pipe 1 from the outer surface 1a is provided between the clamping means 15 and 16. As the outer heating means 20, a high-frequency heating method, a medium-frequency heating method, or the like is adopted.
It is configured to allow insertion of the round steel pipe 1. The outer heating means 20 is movable in the longitudinal direction A of the round steel pipe 1 by the operation of the feeder 21, and the feeder 21 employs a screw feed type or a cylinder type.

In FIGS. 1, 3 and 5, a recessed annular thickened portion is formed between the clamping means 15 and 16 and the place where the heating means 20 is disposed.
An outer mold 25 which can freely contact and separate from a is provided.
The outer mold 25 is composed of a pair of left and right split dies 26A and 26B, and these split dies 26A and 26B are configured to be able to abut and separate from each other by the operation of actuators (such as cylinder devices) 30A and 30B. At that time, the contact and separation are performed stably and smoothly by being guided by the guide devices 31A and 31B.

The relative position and operation of the outer heating means 20 and the outer mold 25 are such that when the split molds 26A and 26B are moved away from each other, the split molds 26A and 26B are moved apart from each other.
The outer heating means 20 is movable in the longitudinal direction A through the space 26B, and when the outer heating means 20 moves to one end in the longitudinal direction A, the split dies 26A, 26B can be brought into contact with each other. ing.

The split molds 26A and 26B have a cylindrical shape when moved in contact with each other, and have an inner wall side with a thickened molding portion 27 which is concave and annular when moved in contact with each other.
A, 27B are formed. Here, the thickening molding section 27
A and 27B are thickened molding surfaces 28A and 28B of a predetermined length.
And a ring portion forming surface 2 further recessed from two places (one or more places) of the thickened forming surfaces 28A and 28B.
9A and 29B. Each molding surface 28A, 28B, 2
Both end faces in the longitudinal direction A of 9A and 29B are appropriately inclined so that they can be easily removed from the mold, and each corner portion is appropriately formed with an R.
Surface. As the outer mold 25, a water-cooled type is adopted.

The inner mold 35 is opposed to the outer mold 25 and can be freely positioned on the inner surface 1b of the round steel pipe 1 at the heating location.
Is provided. The inner mold 35 has a cylindrical shape, and is positioned in the round steel pipe 1 with its outer surface 35a in contact with the inner surface 1b of the round steel pipe 1. And the inner mold 35,
It is supported by a fixing portion 38 provided outside via a connecting member 36 and a stay 37. As the inner mold 35, a water-cooled type is adopted.

Hereinafter, the function of increasing the wall thickness of the tubular body in the first embodiment will be described. First, as shown in FIG. 2, the round steel pipe 1 before the partial wall thickening is applied to the support means 1.
It is carried in (moved) from one end to the other end through one group of drum-shaped support rolls 12. At the time of this carrying in, in the outer die 25, the split dies 26A and 26B are moved away from each other as shown in FIG.
Is moved to one end side (or the other end side) as shown in FIG.

As described above, the round steel pipe 1 carried from one end to the other end is inserted from the clamp means 15 to the outer heating means 20 and the clamp means 16 and the inner die 35 is inserted into the round steel pipe 1. Is inserted. Then, by performing the predetermined amount of movement, as shown in FIG. 1, the thickened portion B is located between the pair of clamp means 15 and 16 and within the working range of the outer heating means 20.

Next, both clamping means 15 and 16 are clamped, whereby both outer portions of the thickened portion B of the round steel pipe 1 are clamped. At this time, the round steel pipe 1 is accurately configured so as not to be pressed more than necessary against the hourglass-shaped support roll 12 by the clamping force, and the pressing force is avoided.

The round steel pipe 1 is clamped by both clamping means 15 and 16.
After is clamped, as shown by the solid line in FIG. 1, local heating of the facing portion is performed by the outer heating means 20 facing the one end side of the thickened portion B. After heating to a predetermined temperature, the outer heating means 20 is moved to the other end as shown by the phantom line in FIG.
As shown in (1), the pair of left and right split dies 26A, 26B are brought into contact with each other by the operation of the actuators 30A, 30B.

In this state, the other clamping means 16 is moved closer to the one clamping means 15. As a result, as shown by the solid line in FIG.
A compressive force in the longitudinal direction A is applied between 5, 5 and 16, and the compressive force increases the thickness of a part of the material of the heating part in and out, whereby the thickened part 2 and the ring part 3 are formed. . At this time,
The amount of increase in the thickness inward is regulated by abutting against the outer surface 35a of the inner mold 35, whereby the inner surface 2b of the thickness increase portion 2 is shaped.
In addition, the amount of wall thickness increase outward is press-fitted into the wall thickness forming portions 27A and 27B, and is regulated by being brought into contact with the wall thickness forming surfaces 28A and 28B and the ring portion forming surfaces 29A and 29B. 2 and the outer surface 3a of the ring 3 are shaped.

At this time, since a compressive force is applied by the two clamping means 15 and 16 located near the heating unit, a sufficient compressive force is uniformly applied to this heating unit. Suitable formation of the thickened portion 2 and the ring portion 3 can be performed, and there is no possibility that the non-heated portion of the round steel pipe 1 is deformed.

Next, the separating dies 26A and 26B are moved apart.
Heating of the next location by the movement of the outer heating means 20 to one end side shown by the phantom line in FIG. The increase in the thickness of the thickened portion 2 in the longitudinal direction A toward the clamp means 16 is performed as shown by the imaginary line in FIG. By this repetition, as shown in FIG. 7, the thickened portions 2A having a predetermined length in the longitudinal direction A are formed in a state where the thickened portions 27A and 27B are completely buried, and the ring is formed at two places. The part 3 is formed. The thickness T of the thickened portion 2 + the ring portion 3 is formed to be two to three times the thickness t of the round steel pipe 1.

Thereafter, the split dies 26A and 26B are moved away from each other, and the clamps by the two clamping means 15 and 16 are released. Note that the round steel pipe 1 is in a state in which the length in the longitudinal direction A is slightly reduced by forming the thickened part 2 and the ring part 3. Then, the round steel pipe 1 on which the thickened part 2 and the ring part 3 are formed is carried out by the carrying force of the support means 11.

As described above, the thickened portion 27 of the outer mold 25 is formed.
By the shaping by A and 27B, the outer surface 2a of the thickened portion 2 and the outer surface 3a of the ring portion 3 can have uniform outer dimensions and can be smoothed. In this manner, the thickened portion 2 and the ring portion 3 are protruded only on the outer surface 1a side and the outer surface 2a is formed.
The round steel pipe 1 in which the a, 3a and the inner surface 2b are shaped, that is, the round steel pipe 1 as shown in FIG. 8B is naturally cooled on a cooling floor or the like.

When the round steel pipe 1 as a product is used, for example, for a column and a beam is connected to the ring 3, the outer surface 3a of the ring 3 has a uniform outer dimension as described above. Moreover, since it is smoothed, there is little gap between them or a uniform and small gap, so that good welding (connection) can be performed, and welding accuracy and strength can be further improved.

Next, a second embodiment of the present invention will be described with reference to FIG.
It will be described based on. That is, the outer diameter of the inner mold 35 is slightly smaller than the inner diameter of the round steel pipe 1, and the inner surface 2 b is shaped by this small outer diameter when the thickened portion 2 is formed. I have.

According to the second embodiment, as shown in FIG. 8C, the thickened portions 2 project in a ring shape from the outer surface 1a and the inner surface 1b of the round steel pipe 1, respectively. It may be a round steel pipe 1.

Next, a third embodiment of the present invention will be described with reference to FIG.
Description will be made based on 0. That is, the outer diameter of the inner mold 35 is
The diameter is made considerably smaller than the inner diameter of the round steel pipe 1, and the thickened portions 27A, 27B of the split dies 26A, 26B are
Straight forming surfaces 32A, 32B having the same diameter as the outer diameter of the round steel pipe 1
And the ring forming surfaces 29A and 29B.

According to the third embodiment, a part of the material of the heating portion is increased in and out of the heating portion by the compressive force, and the thickness of the thickening portion 2 is increased.
And the ring portion 3 are formed. At this time, the amount of increase in the thickness inward is regulated by contacting the outer surface 35a of the inner mold 35, and the inner surface 2b of the increase portion 2 is shaped. In addition, most of the wall thickness increase toward the outside is caused by the straight molding surfaces 32A, 3A.
2B, and a part is press-fitted into the thickened molding portions 27A and 27B, and the ring molding surface 29 is formed.
A, 29B regulates the outer surface 3a of the ring portion 3 by being abutted. As a result, as shown in FIG. 8 (D), only the ring portion 3 protrudes from the outer surface 1a of the round steel tube 1 and the thickened portion 2 protrudes from the inner surface 1b of the round steel tube 1. Can be 1.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
1 will be described. That is, the inner heating means 39 is provided on the other end side of the inner mold 35. As the inner heating means 39, in addition to a high-frequency heating method, a medium-frequency heating method, or the like, a burner method or the like can be employed. The stay 37 is configured to be reciprocally movable in its length direction by the operation of a push-pull drive device (not shown).

According to the fourth embodiment, as shown by the solid line in FIG. 11, when the outside heating means 20 opposed to one end of the thickened portion B performs local heating of the opposed portion. In addition, the inside heating means 39 is opposed to the inside of the one end side of the thickened portion B, and the local heating of the facing portion is performed from the inside, so that the local heating can be performed simultaneously from inside and outside. Then, as shown by the imaginary line in FIG. 11, the outer heating means 20 is moved to the other end side, and the pair of left and right split dies 26A and 26B are brought into contact with each other. When the mold 2 and the ring portion 3 are formed, the inner mold 35 is slightly moved to the other end side to shape the inner surface 2b, and the inner heating means 39 moved together with the inner mold 35 prepares a spare for the next location. Heating is performed.

As described above, according to the fourth embodiment, the heating of the target portion can be performed quickly and sufficiently from both the inside and the outside, so that the entire work of the partial thickness increase can be performed more accurately and efficiently. I can do it.

Next, a fifth embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIGS. That is, a square steel pipe 5 having a square shape is used as another example of the pipe body. Here, the thickness, diameter, and material of the square steel pipe 5 are the same as those of the round steel pipe 1 described above. The support means 11 is configured to support and convey the square steel pipe 5 with the corners in the vertical and horizontal directions. The clamping means 15 and 16, the outer heating means 20, the outer mold 25, the inner mold 35, etc.
Are configured in accordance with the cross-sectional shape and direction of the device.

According to the fifth embodiment, the thickened portion 6 and the ring portion 7 are formed in the same manner as described above. As a result, as shown in FIG. 14A, the thickened portion 6 and the ring portion 7 can be formed into the square steel pipe 5 in which only the outside is protruded and the outer surfaces 6a, 7a and the inner surface 6b are shaped.

By forming the square steel pipe 5 as in the second embodiment, as shown in FIG. 14B, the thickened portion 6 is projected both inside and outside. Steel pipe 5
And Further, by forming the square steel pipe 5 as in the third embodiment, as shown in FIG. 14C, the thickened portion 6 is formed to protrude only inside and the ring portion 7 is formed. Can be formed as a square steel pipe 5 by protruding only to the outside.

Next, a sixth embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIGS. In other words, the pipe part thickening equipment 40 is provided with the pipe receiving means 41 for receiving the round steel pipe 1 with the pipe axis 1A being vertical. The pipe receiving means 41 is constituted by an upward receiving base 43 provided on the fixing part 42 side, a guide roll device 45 arranged on the frame 44 from the fixing part 42 side, and the like. Here, the guide roll device 45 is configured by arranging a set of four (plural) hourglass rollers 46 for guiding the outer surface 1a of the round steel pipe 1 in a plurality of stages in the vertical direction. The hourglass roller group 46 of the guide roll device 45 is configured to be freely adjustable in position and exchangeable according to a change in the diameter of the round steel pipe 1 or the like.

As a result, the outer surface 1a of the round steel pipe 1, which has been carried (moved) vertically from above, is guided by the hourglass-shaped rollers 46 of the guide roll device 45 and the lower end surface of the round steel tube 1 is received by the receiving base 43. In the abutted state, the pipe shaft center 1A is received vertically by the pipe receiving means 41.

A clamp means 47 is provided which is capable of holding above the intended thickening point B of the round steel pipe 1 received by the pipe receiving means 41, and the clamp means 4
Numeral 7 is configured to be movable (movable up and down) in the direction of the tube axis 1A. That is, the clamp means 47 is configured to allow the insertion of the round steel pipe 1, and is configured to be able to clamp the outer surface 1a of the inserted round steel pipe 1 from the outside.

The clamp means 47 is provided, for example, on the lift table 48 side, and is movable by raising and lowering the lift table 48 by a lift device (screw feed type, cylinder type, etc.) 49 provided on the fixed portion 42 side. Becomes An example of the compressing force applying means 50 for applying the compressing force in the longitudinal direction A to the round steel pipe 1 by moving the clamp means 47 is constituted by the elevating table 48 and the elevating device 49.

Below the clamping means 47, an outer heating means 20 for heating the thickened portion B of the round steel pipe 1 is provided. It is movable in the direction of the center 1A. An outer mold 25 is provided below the clamping means 47 and at a location where the heating means 20 is disposed. And the outer mold 25
And an inner mold 35 that can be freely positioned on the inner surface 1b of the round steel pipe 1 at the heating location. In addition,
Outer heating means 20, feeding device 21, outer mold 25, inner mold 35
And the like have different directions and operating directions, but have the same configuration as that of the above-described first embodiment, and the details are omitted.

Hereinafter, the function of increasing the wall thickness of the pipe in the sixth embodiment will be described. First, the round steel pipe 1 before partial thickening is carried (moved) from above to below via carrying means (not shown) such as a crane.
That is, the round steel pipe 1 is carried in from the upper side to the lower side with the pipe axis 1A being vertical, and at this time, the round steel pipe 1 is inserted from the clamp means 47 to the heating means 20 and the round steel pipe 1 The mold 35 is inserted.

The round steel pipe 1 is guided by the pipe receiving means 41 with the lower outer surface 1a being guided by the group of hourglass rollers 46 of the guide roll device 45 and the lower end face being in contact with the receiving base 43. The axis 1A is received as a vertical shape. As a result, the thickened portion B is
7 and within the operating range of the heating means 20. Next, the clamping means 47 is clamped, whereby the upper part of the thickened portion B of the round steel pipe 1 is clamped.

In this state, the outer heating means 20, the outer mold 25, the inner mold 35, and the like are operated in the same manner as in the first embodiment described above, whereby the thickening portion 2 and the ring portion 3 are formed. Will be At this time, the clamp means 47 which clamps the upper part of the thickening portion B is moved downward by the operation of the compressive force applying means 50. As a result, a compressive force in the direction of the pipe axis 1A is applied to the lower portion from the clamp means 47, whereby the heating portion is increased in and out by the compressive force, and the thickened portion 2 is formed. Become. At this time, molding of the thickened portion 2
It is performed from below to above.

Since a compressive force is applied via the clamp means 47 located near the heating section during such molding, a sufficient compressive force is uniformly applied to the heating section. Thus, a suitable thick portion 2 and ring portion 3 can be formed, and the non-heated portion of the round steel pipe 1 is not likely to be deformed. Moreover, since the round steel pipe 1 is arranged with its pipe axis 1A being vertical, even if, for example, the heating portion heated at a high temperature may be deformed in a drooping shape due to its own weight or the like, the drooping direction is not changed. Compression direction,
Thus, the suitable thickening portion 2 and ring portion 3 can always be formed, and the heating temperature is not so much concerned and the temperature control becomes easy. Then, the round steel pipe 1 on which the thickened part 2 and the ring part 3 are formed is carried out upward.

Thus, a round steel pipe 1 as shown in FIG. 8B is obtained. By forming and operating the forming part in the same manner as in the above-described second embodiment, FIG.
(C) is obtained, and by forming and operating the formed part in the same manner as in the third embodiment described above, a round steel pipe as shown in FIG. A steel pipe 1 is obtained. Furthermore, by installing equipment for the square steel pipe 5, FIG.
The square steel pipe 5 as shown in FIGS.

It is to be noted that an embodiment in which the inner heating means 39 similar to the fourth embodiment is incorporated in the sixth embodiment is also possible. In each of the above-described embodiments, the inner mold 35 is used.
An embodiment that does not require the above is also possible.

In each of the above embodiments, the round steel pipe 1 and the square steel pipe 5 having the thickened portions 2 and 6 and the ring portions 3 and 7 are formed.
Is heated as uniformly as possible by a heating furnace or the like (for example, at a temperature exceeding the A3 transformation point) to reheat the thickened portions 2 and 6 and the ring portions 3 and 7 and to heat other portions in the same manner. By heating to a temperature, it is possible to remove the stress generated inside the pipe, to recover from the remarkable deterioration of the material due to the processing, and to obtain a high-quality thickened pipe (product) by homogenizing the performance. When used as a steel column material for building, stress is smoothly transmitted from the thickened parts 2, 6 and the ring parts 3, 7 to the main part of the round steel pipe 1 and the square steel pipe 5 during an earthquake, Combined with the superiority of the shape of the tubular body (product), further absorption of seismic energy can be expected.

In each of the above embodiments, the heating means 20
After the local heating is performed by, for example, the compressive force in the longitudinal direction A is applied, the thickened portion 2 and the ring portion 3 are formed. 2
A method in which local heating is performed by 0 or the like may be used.

In the above-described first embodiment, the compression force is applied by moving one of the clamping means 16 closer to each other. Good.

In each of the above-described embodiments, the thickened portions 2 and 6 and the ring portions 3 and 7 are formed in the round steel pipe 1 and the square steel pipe 5. Is heated as uniformly as possible by a heating furnace or the like, and is formed into a square shape by hot forming, whereby a square steel tube 5 having a thickened portion 6 and a ring portion 7 can be obtained. Further, in this case, the above-described effect of overall heating can be obtained automatically.

In each of the above embodiments, the length of the thickened portions 2 and 6 in the longitudinal direction A is arbitrarily set, and the thickened portions 2 and 6 are formed at one or a plurality of locations. Is what is done. Further, the length, the amount of protrusion, the number, and the like of the ring portions 3 and 7 are arbitrarily set.

[0064]

According to the first aspect of the present invention, the outer surface of the thickened portion in the heated state can be shaped by the thickened molded portion of the outer mold, so that the outer surface of the thickened portion has a uniform outer dimension. And smoothing. Further, the thickened portion can be formed quite thick. Therefore, for example, when the shaped pipe is used as a support and the beam is connected to the thickened portion, the outer surface of the thickened portion and the beam having uniform outer dimensions are smoothed. Since there is little gap between them or a uniform and small gap, good welding (connection) can be performed, and welding accuracy and strength can be further improved.

According to the second aspect of the present invention,
The ring portion can be protruded and formed simultaneously with the formation of the thickened portion, and the outer surface of the ring portion can be shaped. Therefore, when connecting the beam material to the ring portion, welding accuracy and strength can be further improved.

According to the third aspect of the present invention, the outer surface and the inner surface of the thickened portion can be shaped simultaneously with the formation of the thickened portion. Further, according to the above-mentioned claim 4 of the present invention, the heating of the target portion can be simultaneously and promptly and sufficiently performed from both the inside and the outside, so that the entire work of the partial thickening can be performed more accurately and efficiently. Can be.

Further, according to the fifth aspect of the present invention, it is possible to obtain a round steel pipe or a square steel pipe integrally having a thickened portion and a ring portion. According to the invention of claim 6 of the present invention described above, both sides of the target portion of the tube are clamped by the clamp means, and the target portion is heated by the heating means, and the outer mold is placed on the outer surface of the heated portion. After the abutment with the pipe, the clamp means is moved relatively closer to each other to apply a compressive force in the longitudinal direction to the pipe body, whereby a thickened portion can be formed at a target location. The method for partially increasing the body thickness can be suitably realized.

According to the seventh aspect of the present invention, one end side of the tube is received by the tube receiving means, and the target portion is heated by the heating means, so that the outer surface of the heated portion is exposed. After contacting the mold, a compressive force applying means is applied to the other end of the tube to apply a longitudinal compressive force to the tube, thereby forming a thickened portion at a target location. Thus, the method for partially increasing the thickness of the tubular body according to claim 1 can be suitably realized. Further, since the tube can be formed as a vertical shape, for example, even if the heated portion heated at a high temperature may be sagged due to its own weight or the like, the sagging direction becomes the compression direction, so that the wall thickness is always suitable. The formation of the portion can be performed, and the heating temperature can be easily controlled without much concern.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of the present invention, and is a partially cutaway side view at the time of a wall-thickening operation in a pipe wall-thinning facility.

FIG. 2 is a partially cutaway side view of the pipe body when the pipe body is carried in the partial wall thickness increasing equipment.

FIG. 3 is a partially cutaway front view of the tubular body at the time of heating in the partial thickening facility.

FIG. 4 is a partially cutaway front view at the start of thickening in the partial thickening facility of the pipe body.

FIG. 5 is a longitudinal sectional side view of a main part at the time of starting the thickening in the partial thickening facility of the pipe body.

FIG. 6 is a vertical cross-sectional side view of a main part during a wall-thickening operation in a partial wall-thickening facility of the pipe body.

FIG. 7 is a longitudinal sectional side view of a main part of the tubular body at the time of completion of thickening in the partial thickening facility.

FIG. 8 is a partially cutaway perspective view showing the various round steel pipes.

FIG. 9 shows the second embodiment of the present invention, and is a longitudinal sectional side view of a main part at the time of completion of thickening in a partial wall thickening facility for a tubular body.

FIG. 10 shows the third embodiment of the present invention, and is a longitudinal sectional side view of a main part at the time of completion of wall-thickening in a pipe wall-thickening facility.

FIG. 11 shows a fourth embodiment of the present invention, and is a longitudinal sectional side view of a main part at the time of starting to increase the thickness of a pipe body with a partially increased thickness.

FIG. 12 shows the fifth embodiment of the present invention, and is a partially cutaway front view at the start of thickening in a pipe part thickening facility.

FIG. 13 is a vertical cross-sectional side view of a main part during a wall-thickening operation in a partial wall-thickening facility of the pipe body.

FIG. 14 is a partially cutaway perspective view showing the various types of square steel pipes.

FIG. 15 shows a sixth embodiment of the present invention, and is a partially cutaway side view at the time of a wall-thickening operation in a pipe wall-thinning facility.

FIG. 16 is a longitudinal sectional side view of a main part at the time of a wall-thickening operation in a partial wall-thickening facility of the pipe body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Round steel pipe (tube) 1A Pipe axis 1a Outer surface 1b Inner surface 2 Thickened portion 2a Outer surface 3 Ring portion 5 Square steel tube (tubular body) 5a Outer surface 5b Inner surface 6 Thickened portion 6a Outer surface 7 Ring portion 7a Outer surface 10 Partly thickened Equipment 11 Supporting means 15 Clamping means 16 Clamping means 19 Compressive force applying means 20 Outer heating means 25 Outer mold 26A Split mold 26B Split mold 27A Thickening part 27B Thickening part 28A Thickening surface 28B Thickening surface 29A Ring Part forming surface 29B Ring part forming surface 32A Straight forming surface 32B Straight forming surface 35 Inner die 35a Outer surface 39 Inner heating means 40 Partial thickening equipment 41 Pipe receiving means 47 Clamp means 50 Compressive force applying means A Longitudinal B increase Thick part (target part) T Thickness of thickened part 2 + ring part 3 t Thickness of round steel pipe (tube)

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI B21K 21/16 B21K 21/16

Claims (7)

[Claims] 1. A target portion of a tube is heated, and an outer mold having an annular thickened portion is positioned on an outer surface of the heated portion. A method for partially increasing the thickness of a tubular body, comprising applying a compressive force to sequentially press-fit a part of a material at a heated portion into a thickened molding portion. 2. The method according to claim 1, wherein the wall-thickening forming portion has a concave ring-shaped ring-portion forming surface. 3. The method according to claim 1, wherein the outer mold is located on the outer surface of the heated portion, and the inner mold is located on the inner surface of the heated portion. 4. Heating a target portion of the tube by heating means from the outside facing the outer surface of the tube and heating means from the inside facing the inner surface of the tube. The method for partially increasing the thickness of a tubular body according to any one of claims 1 to 3, wherein: 5. The method according to claim 1, wherein the pipe is a round steel pipe or a square steel pipe. 6. A pair of clamping means capable of holding two positions in the longitudinal direction of the tube with a target portion of the tube in the middle, and moving these clamps relatively close to and away from the tube. Compressive force applying means for applying a compressive force in the longitudinal direction, heating means for heating a target portion of the tubular body, and a concave annular thickened molded portion formed so as to be able to contact and separate on the outer surface of the heated portion Partial wall-thickening equipment for a tubular body provided with an outer mold. 7. A tube receiving means for receiving one end of a tube, a compressing force applying means acting on the other end of the tube to apply a longitudinal compressive force to the tube, and an object of the tube. Characterized in that a heating means for heating a portion to be heated, and an outer mold which is formed with a concave annular thickened molded portion and which can be freely contacted and separated on the outer surface of the heated portion, are provided. Facility.