JP3305186B2 - How to attach inner diaphragm to steel pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of attaching an inner diaphragm to a steel pipe which is used to attach an inner diaphragm to a column when connecting columns of a steel structure with beams. is there.

[0002]

2. Description of the Related Art Conventionally, a diaphragm is attached to a support column by, for example, a method shown in FIG.
Was done in That is, the column is cut (divided) into a lower column 110, a panel zone column 111, and an upper column 112 in the longitudinal direction. And lower strut 11
0 on the upper end of the lower diaphragm 11 via the backing material 113.
4 is welded, and the lower end of the column 111 is welded on the lower diaphragm 114 via the backing material 115. Further, an upper diaphragm 117 is welded to the upper end of the column 111 via a backing material 116, and an upper support 11 is provided on the upper diaphragm 117 via a backing material 118.
Is welded at the lower end.

[0003] The beam (mainly H-shaped steel) 120 is connected to the column 119 formed in this manner by welding the free end of the beam 120 to both the diaphragms 114 and 117 and the column 111. I was And both diaphragms 114 and 11
7 played the role of stress transmission.

However, according to the above-described conventional structure, the support pillar 119, that is, the square steel pipe is cut into a plurality of pieces in the longitudinal direction, and the cut surfaces are each beveled and then the diaphragms 114 and 117 are attached. In addition, there is a problem that a large amount of time and cost are required for the cutting operation and the beveling operation, and there are many welding points.

Therefore, as a method of not cutting the rectangular steel pipe, there is provided a method of positioning and welding a diaphragm in an extremely thick large-diameter rectangular steel pipe as disclosed in Japanese Patent Application Laid-Open No. 7-238636, for example. In this conventional method, an inner diaphragm having a backing metal temporarily attached and welded to both sides thereof is inserted into a square steel pipe, engaged with a knock pin fitted in a through-hole, positioned at a predetermined position, and then placed at the insertion port side. After the backing metal is tack-welded to the inner wall of the rectangular steel pipe, the inner wall of the rectangular steel pipe and the outer periphery of the inner diaphragm are elect-slag welded using the through holes.

[0006]

In the above-mentioned construction method in which the rectangular steel pipe is not divided, the outer diameter of the backing metal is allowed to contact the inner wall of the rectangular steel pipe without any gap, for example, by allowing a gap of about 0.5 mm. Therefore, when the inner diaphragm is inserted into the rectangular steel pipe, the inner diaphragm is caught or jammed, so that the inner diaphragm cannot be easily inserted. Further, when the inner surface of the rectangular steel pipe has changed in irregularities, the insertion itself cannot be performed. To cope with this, it is sufficient to make a sufficient gap, but if this gap is large, the molten metal of the electroslag welding is placed in the welding space surrounded by the square steel pipe, the inner diaphragm, and both backing metals. Stagnation, the molten metal may leak to the outside through a gap between the backing metal and the inner surface of the rectangular steel pipe, and good welding may not be performed.

Therefore, according to the first aspect of the present invention, the inner diaphragm can be easily and smoothly inserted into the steel pipe with a sufficient gap, and the gap is automatically filled, and the welding is performed by melting. It is an object of the present invention to provide a method of attaching an inner diaphragm to a steel pipe, which can perform metal without leaking to the outside.

The invention according to claim 2 provides a method for mounting an inner diaphragm in a steel pipe, in which a gap can be formed and a gap can be filled by utilizing heating expansion and cooling shrinkage during heat forming of the steel pipe. It is intended for.

[0009]

In order to achieve the above-mentioned object, a method for mounting an inner diaphragm in a steel pipe according to claim 1 of the present invention comprises preparing an inner diaphragm having a backing material integrated therein. Aside from this, the diaphragm is
Inserting the steel pipe to the predetermined position in the expanded steel pipe, bringing the inner surface of the steel pipe into contact with the outer surface of the backing material by cooling and shrinking the steel pipe, and then welding the inner diaphragm and the backing material to the inner surface of the steel pipe. It is a characteristic.

[0010] Therefore, according to the first aspect of the present invention, the inner diaphragm can be easily formed without being caught or clogged by utilizing a sufficient gap generated between the outer surface of the backing material and the inner surface of the steel tube due to the thermal expansion of the steel tube. It can be inserted smoothly. Then, the gap is automatically filled by the cooling shrinkage of the steel pipe, and the inner diaphragm side can be firmly bonded to the steel pipe by utilizing the fact that the inner surface of the steel pipe abuts (presses) on the outer surface of the backing material. Thereby, the welding space can be formed in a sealed manner by the inner surface of the steel pipe, the inner diaphragm, and the backing material. It can be performed well without leaking to the inner diaphragm surface.

According to a second aspect of the present invention, there is provided a method of attaching an inner diaphragm to a steel pipe, wherein the inner diaphragm is inserted into a hot-formed steel pipe. Things.

Therefore, according to the second aspect of the present invention, the steel pipe can be made to have good properties by hot forming, the inner diaphragm can be inserted by utilizing the thermal expansion at the time of hot forming, and the cooling shrinkage can be utilized. Can be combined.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
The state adopted when hot forming a square steel pipe will be described with reference to FIGS.

In FIGS. 6 and 7, for example, in manufacturing a large-diameter rectangular steel pipe, a square hollow polygonal steel pipe 2 having seam welds 1 at two locations is used. At that time, polygonal hollow steel tube 2, the phase inner surface width W ₁ of opposed flat plate portions 2A is formed in the wider dimension than the inner surface width of the flat portion of the final product (which will be described later.) The corner 2B the radius of curvature R ₁ is larger molded than the radius of curvature of the corner portion of the final product.

[0015] The polygonal hollow steel pipe 2 thus formed is
It is carried on the carrying-in floor device 5. Here, the loading floor device 5 is of a conveyor type, supports a plurality of hollow hollow steel pipes 2 in parallel, and transports the hollow steel pipes 2 in a horizontal direction perpendicular to the length direction. The polygonal hollow steel pipe 2 conveyed to the terminal end of the loading floor device 5 is heated by a heating furnace 7 via a roller conveyor 6.
And is conveyed in the heating furnace 7 in the longitudinal direction, and is heated at a high temperature A during the conveyance.

Polygonal hollow steel pipe 2 heated to a predetermined temperature
Is carried out of the heating furnace 7 and is carried into the former square steel tube forming mill 8. In this pre-stage square steel tube forming mill 8,
Hot-forming via a plurality of the clutch forms a roll 9 (molding temperature, A ₃ transformation point or above) and performs pre-stage of drawing is performed on polygonal hollow steel tube 2. Next, the polygonal hollow steel pipe 2 is carried into a post-stage square steel pipe forming mill 10. In the subsequent RHS molding mill 10, which performs hot forming via a plurality of flat roll 11 (the molding temperature, A ₃ transformation point or higher), stop the subsequent (last stage) to the polygonal hollow steel tube 2 Forming is performed, and thus a large-diameter, square-shaped rectangular steel pipe 3 having a predetermined size is formed.
Are hot formed.

As described above, the polygonal hollow steel pipe 2 is subjected to multiple-stage drawing (or single-stage drawing) by the front-stage square steel tube forming mill 8 and the rear-stage square steel tube forming mill 10 to be a final product. A square steel pipe 3 can be manufactured. At this time, by the above-described drawing, the inner surface width dimension W of the opposed flat plate portion 3A of the rectangular steel pipe 3 is set to be the polygonal hollow steel pipe 2.
Narrow the inner surface width W ₁ of, i.e. is shaped so that W <W _1, also the radius of curvature R of the corner portion 3B is smaller than the radius of curvature R ₁ of the corner portion 2B of the polygonal hollow steel tube 2 ,
That it is molded so that R <R _1, the four corners of the corner R are aligned.

Here, the inner surface width dimension W of the rectangular steel pipe 3 is the dimension of the final product after being heat-formed and cooled. On the other hand, the inner surface width dimension W + α is wider, that is, W <W + α <W ₁ .

As described above, the corner 2 of the polygonal hollow steel pipe 2
The radius of curvature R of the corner portions 3B of the radius of curvature R ₁ is square tube 3 of B
By being formed into a larger dimension, reasonable forming (press forming) can be easily performed. Further, the polygonal hollow steel pipe 2 whose material (molecular arrangement) is returned to the original state by the high-temperature heating A is changed into a narrow inner surface width W and a radius of curvature R of the corner 3B.
By hot drawing in such a manner as to reduce the residual stress, residual stress is also removed, and a final product with a high section modulus, that is, a square steel pipe 3 can be obtained without changing the material.

Further, by hot drawing, the rectangular steel pipe 3 is completely or almost completely formed from the front end to the rear end. Therefore, the cutting and removing of the front end and the rear end in the post-process is performed by a molding amount. Became unnecessary. Or
Cutting and removal are performed in a short dimension, so that the yield is improved.

In the square steel pipe 3 immediately after hot forming, each flat plate portion 3A has a straight surface, and the R of the corner portion 3B is sharp and the section modulus is high. In addition, since the polygonal hollow steel pipe 2 has a regular square shape, the conveyance by the roller conveyor 6 can be always performed in a fixed direction using one flat plate portion 3A. Can always be performed with the position of the seam welded portion 1 aligned in a certain direction.

In the vicinity of the square steel tube forming mills 8 and 10, a single point such as a necessary part (before the front square steel tube forming mill 8, between the double square steel tube forming mills 8 and 10, after the rear square steel tube forming mill 10, etc.) (Or a plurality of locations), the required number of descaler devices 12 are provided. The descaler device 12 injects water with water pressure applied to the square steel pipe 3 and the like. The water injection removes mill scale and the like, and can improve the surface skin.

As described above, the hot-formed square steel pipe 3 is received by the cooling floor device 20. This cooling floor device 20
Supports a plurality of rectangular steel pipes 3 in parallel, and conveys them in a horizontal direction perpendicular to the length direction. During the transportation in the cooling floor device 20, the rectangular steel pipe 3 is radiated B, that is, gradually cooled in an air cooling system.

As shown in FIGS. 6, 8 to 10, outside the starting end of the cooling floor device 20, a receiving conveyor device 15 for receiving the square steel pipe 3 from the rear-stage square steel tube forming mill 10 is provided. I have. The receiving conveyor device 15 is of a roller conveyor type and includes a plurality of drive rollers 16 installed at predetermined intervals. The receiving conveyor device 15 is included in the receiving conveyor device 15.
A transfer device for transferring the upper rectangular steel pipe 3 to the start end of the cooling floor device 20
17 are provided. The transfer device 17 is composed of a group of supports 18 that are movable in the horizontal direction perpendicular to the conveying direction of the receiving conveyor device 15 and that can move up and down.

The cooling floor device 20 is, for example, an eight-row (multiple-row) chain conveyor device 21 that can be driven intermittently in synchronization.
Are arranged side by side. Each chain conveyor device 21 has a similar configuration, and is configured by disposing a drive-type roller chain 23 on a conveyor frame 22, for example.

A post-stage cooling floor device 25 is provided continuously to the end of the cooling floor device 20. The latter cooling floor device 25 has the same configuration as the cooling floor device 20 and is configured by arranging a plurality of chain conveyor devices 26 in parallel, and each of the chain conveyor devices 26 includes a conveyor frame 27, a roller chain 28, and the like. It consists of.

A take-out conveyor device 30 for receiving the rectangular steel pipe 3 from the latter cooling floor device 25 is provided outside the terminal end of the latter cooling floor device 25. The take-out conveyor device 30 is similar to the receiving conveyor device 15 described above, and includes a group of drive rollers 31 and the like. In the take-out conveyor device 30, a transfer device 35 for taking out the rectangular steel pipe 3 on the post-stage cooling floor device 25 and transferring it to the conveyor device 30 is provided. The transfer device 35 includes a support 36 and the like that operate in the same manner as the transfer device 17 described above.

An inner diaphragm supply device 50 for supplying the inner diaphragm 40 to a predetermined position in the rectangular steel pipe 3 supported laterally by the cooling floor device 20 is disposed in the cooling floor device 20. .

The inner diaphragm 40 has a rectangular plate shape as shown in FIGS. 1 and 2, and its outer dimension is such that a sufficient gap is formed between the inner surface of the rectangular steel pipe 3 and the inner surface 3a of the flat plate portion (the inner surface of the steel pipe). Is set to occur. At the center of the inner diaphragm 40, a through portion 41 having a predetermined inner diameter (described later) is formed. Backing members 42 are integrated by welding on both sides of the inner diaphragm 40 and the outer periphery thereof. Here, the backing material 42 is formed by integrating flat steel or square steel having a rectangular cross section in a frame shape, and is integrated with the side surface of the inner diaphragm by welding through the inner surface.

At this time, the outer dimension L of the backing material 42 is larger than the outer dimension of the inner diaphragm 40, and is formed to be equal to (slightly larger) the inner surface width dimension W of the square steel pipe 3 as the final product. . However, the rectangular steel pipe 3 is thermally expanded as described above, and a gap (about 5 to 6 mm) S is formed between the flat plate inner surface 3a and the backing material outer surface 42a during the thermal expansion.
Will occur.

The inner diaphragms 40 are combined into a single set by connecting two spaced apart members via a rod 45, and a backing material 42 is integrated with each inner diaphragm 40. .

As shown in FIGS. 1 to 4 and FIGS. 8 to 10, the inner diaphragm supply device 50 is provided on one side of the cooling floor device 20, and an arm rod 52 slides on the main body 51 side. It is provided movably. The arm rod 52 is cylindrical, and its sliding is performed via a guide device (not shown).
It is configured so that it can be freely inserted into and removed from the inside. At that time
The reciprocating sliding of the 52 is performed by the operation of a cylinder device 53 provided between the cylinder 52 and the main body 51.

The arm rod 52 is provided with an inner diaphragm supporting device 60 capable of supporting and releasing the inner diaphragm 40 by operation from the base end side of the arm rod 52. That is, a small-diameter cylindrical portion 61 is integrated with the tip of the arm rod 52, so that a step 62 is formed between the arm rod 52 and the small-diameter cylindrical portion 61. Here, the outer diameter of the small-diameter cylindrical portion 61 is set smaller than the inner diameter of the through portion 41. Therefore, the inner diaphragm 40 is externally fitted to the small-diameter cylindrical portion 61 through the through portion 41, and the side surface of the inner diaphragm abuts on the step portion 62.

An inner cylindrical body 63 is fitted inside the arm rod 52. The inner cylindrical body 63 is located at the tip of the inner cylindrical body 63 and at a plurality of locations (or the entire circumference) in the circumferential direction.
The cam bodies 64 are fixed to each other.
Is formed. A plurality of holders 65 having a cam surface 65a to be brought into contact with the cam surface 64a are provided, and these holders 65 are fitted into guide holes 66 formed in the small-diameter cylindrical portion 61, so that the center of the arm rod is formed. It is configured to move toward and away from.

A box-shaped case 67 is fixed to the base end of the arm rod 52, and the base end of the inner cylinder 63 extends into the case 67. And at the base end of the inner cylinder 63 is an inner bracket
A cylinder device 69 for pushing and pulling the inner cylindrical body 63 along the center of the arm rod is provided between the inner bracket 68 and the case body 67 at a plurality of positions around the center of the arm rod. Is provided.

Here, when the inner cylinder 63 is pulled toward the base end by the cylinder device 69, the cam surface 64a and the cam surface 65
As a result, the group of holding members 65 is moved away from the center of the arm and rod and pressed against the inner surface of the through portion 41 of the inner diaphragm 40, whereby the inner diaphragm 40 is held. Also, when the inner cylinder body 63 is pushed and moved to the tip side by the cylinder device 69,
The holding body 65 group is moved closer to the center of the arm rod by the cam surface 64a and the cam surface 65a, and the penetrating portion 41 of the inner diaphragm 40 is moved.
The inner diaphragm 40 is released. The inner diaphragm support device 60 is constituted by 61 to 69 described above.

The plurality of inner diaphragm supply devices 50 are arranged so as to be able to circulate and move on one side of the cooling floor device 20. That is, an endless guide rail 70 is disposed on one side of the cooling floor device 20, and the main body 51 of each of the inner diaphragm supply devices 50 is supported and guided by the guide rail 70 via rollers or the like. It is circulated and moved on an endless path 71 formed outside the rail 70.

At that time, the lower linear portion of the endless path 71 is
The inner diaphragm supply device 50 group is set to have the same level as the rectangular steel tube 3 group conveyed on the cooling floor device 20. The group of inner diaphragm supply devices 50 is configured to be moved by a drive device (for example, a drive chain device) 72 that is operated in synchronization with the transfer speed of the cooling floor device 20.

An end straightening device 75 is provided at the start end of the lower straight portion of the endless path 71. This end straightening device
75 is straightening (expanding) of the end of the hot-formed square steel pipe 3
The positioning (fixing to a fixed position) of the rectangular steel pipe 3 is also performed by the clamp at that time. Note that the positioning may be performed by another device, and if the correction of the edge is unnecessary, the edge correcting device 75 may be omitted.

Hereinafter, the cooling of the rectangular steel pipe 3 and the operation of attaching the inner diaphragm 40 to the rectangular steel pipe 3 in the above embodiment will be described. First, as shown by the solid line in FIG. 1 and FIG. 2, at a position where the inner diaphragm supply device 50 is pulled out (retracted), the backing material 42 is integrated with the inner diaphragm support device 60 and The inner diaphragm 40, which is made into one set, is supported.

That is, one inner diaphragm 40 is fitted to the small-diameter cylindrical portion 61 provided at the tip of the arm rod 52 through the through portion 41 so that the side surface of the inner diaphragm abuts on the step portion 62. . Then, the inner cylinder body 63 is pulled toward the base end side by the cylinder device 69, so that the cam body 64a and the cam surface 65a move the holding body 65 group away from the center of the arm rod to move the inner diaphragm 40. The inner diaphragm 40 is supported by being pressed against the inner surface of the through portion 41. At this time, the phase of the inner diaphragm 40 in the circumferential direction with respect to the square steel pipe 3 is adjusted.

On the other hand, the square steel pipe 3 hot-formed by the latter-stage square steel pipe forming mill 10 is supported by a group of drive rollers 16 of the receiving conveyor device 15 in FIGS. You. Then, the conveyance of the rectangular steel pipe 3 is stopped by abutting the tip of the square steel pipe 3 against the stopper or by detecting the end and stopping the drive.

Next, the rectangular steel pipe 3 on the receiving conveyor device 15 is supplied to the starting end of the cooling floor device 20 by the transfer device 17. That is, with the group of supports 18 positioned below the rectangular steel pipe 3 supported by the receiving conveyor device 15, the support 18 is raised, and the rectangular steel pipe 3 is thereby supported.
Lift by 18 groups. By moving the group of supports 18 to the start end of the cooling floor device 20 and then lowering it, FIG.
As shown in a virtual line of FIG. 9 and FIG.
Is placed on the start end of the chain conveyor group 21 that is intermittently stopped. Thereafter, the support 18 is returned below the receiving conveyor device 15.

The end straightening device 75 is applied to the end of the rectangular steel pipe 3 placed at the start end of the cooling floor device 20 in this manner, thereby correcting (expanding) the end deformed during hot forming. ), And the positioning (fixing to a fixed position) of the rectangular steel pipe 3 is performed by the clamp. At that time, the end straightening device 75
Is moved upward as shown by the imaginary line in FIG. 9 so as to face the end of the rectangular steel pipe 3, and after correcting and positioning the end, is made inoperative by descending movement. After the end straightening device 75 is deactivated in this manner, as shown by the solid line in FIG. 1, the inner diaphragm feeding device 50 is attached to the end of the square steel tube 3 thus straightened.
The inner diaphragm 40 supported on the side is opposed.

In this state, the cylinder device 53 is operated,
The arm rod 52 is protruded from the main body 51 to move the pair of inner diaphragms 40 in the rectangular steel pipe 3 to a predetermined position as shown by the phantom line in FIG. 1, FIG. 2 and FIG. 8 and FIG. Insert. At this time, the outer dimension L of the backing material 42 integrated with the inner diaphragm 40 is smaller than the inner surface width dimension W + α of the rectangular steel pipe 3 at the time of thermal expansion, so that the backing material outer surface 42a and the flat plate portion inner surface 3a Since the gap S is formed therebetween, the inner diaphragm 40 can be inserted without being caught or clogged. Then, the insertion movement of the arm rod 52 is controlled by a control device (not shown) so that the inner diaphragm 40 is at a predetermined position in the rectangular steel pipe 3.

After the supply (insertion) process of the inner diaphragm 40 is completed, the chain conveyor device group 21 is intermittently driven to move the rectangular steel pipe 3 in the transverse direction perpendicular to the length direction thereof. The sheet is intermittently transported by the pitch (predetermined distance). At that time, the inner diaphragm supply device 50 is
By the synchronous drive of 72, it is intermittently moved integrally with the square steel pipe 3 on the endless path 71, so that the relative position between the square steel pipe 3 and the inner diaphragm 40 is maintained.

As described above, the rectangular steel pipes 3 are successively supplied to the starting end of the chain conveyor device 21.
Then, supply (insertion) of the inner diaphragm 40 is performed via the inner diaphragm supply device 50. Such a cooling floor device
The intermittent conveyance of three groups of square steel pipes at 20
It is performed in a state where the distance is kept. This makes the square steel pipe 3
Is gradually cooled under the same ambient temperature.

On the cooling floor device 20, the square steel pipe 3
Is shrunk as it is cooled, and when it is shrunk to the inner surface width W corresponding to the final product, as shown in FIG. 3, the flat plate portion inner surface 3a abuts (presses) on the backing material outer surface 42a.
In addition, it is slightly indented. Thereby, the inner diaphragm 40 side is connected to the square steel pipe 3,
At this time, a sealed welding space X is formed by the inner surface 3a of the flat plate portion, the outer surface of the inner diaphragm 40, and both backing members 42.

At this time, by inserting the inner diaphragm 40 into the hot-formed square steel pipe 3, the flow of air in the square steel pipe 3 at the time of cooling is reduced, and the square steel pipe 3 is formed by the heat retaining effect of air. It can be cooled as a more uniform property in the entire inner cross section.

The pre-cooled rectangular steel pipe 3
When the pressure reaches the end of the cooling floor device 20, the support of the inner diaphragm 40 by the inner diaphragm support device 60 is released, and the arm rod 52 is pulled out.

That is, as shown in FIGS. 4 and 5, in the inner diaphragm support device 60, the cylinder device 69 pushes and moves the inner cylinder 63 toward the distal end, thereby forming the cam surface 64a.
And the cam surface 65a moves the holding body group 65 closer to the center of the arm rod by the guide of the guide hole 66, thereby forming the inner diaphragm.
The inner diaphragm 40 is loosely fitted into the through portion 41, thereby releasing the support to the inner diaphragm 40. Next, the arm rod 52 can be pulled out of the square steel pipe 3 by the cylinder device 53. At this time, the inner diaphragm supporting device 60 can be pulled out of the press-bonded inner diaphragm 40 through the through portion 41 thereof.

Thereafter, the inner diaphragm supply device 50 is intermittently moved on the upper straight portion of the endless path 71 in FIGS. 8 and 10, and is returned to the original position. The pre-cooled rectangular steel pipe 3 is moved from the end of the cooling floor device 20 to the start end of the post-cooling floor device 25, and while being conveyed by the same operation of the post-cooling floor device 25, the subsequent slow cooling is performed. Done.

The rectangular steel pipe 3 which has been cooled in the latter stage and has reached the end of the latter cooling floor unit 25 is taken out by the transfer unit 35 which is operated in the same manner as the transfer unit 17 described above, and transferred to the conveyor unit 30. In addition, it is transported to a leading end cutting device, a trailing end cutting device, a cleaning device,
After being processed by each, it is stored as a product.

The inner diaphragm 40 is welded and fixed to the square steel pipe 3 stored as a product as described above or to the square steel pipe 3 at an appropriate process portion after being taken out from the post-stage cooling floor unit 25.

That is, as shown in FIG. 11, at the welding work site, a support device 80 for supporting and rotating the rectangular steel pipe 3 in a horizontal direction is provided. The support device 80 includes a pair (single or plural) of drive support portions 81, and a floating support portion 82 provided at one (or a plurality of) positions between the drive support portions 81. You.

Each of the supporting portions 80 and 81 includes a lower frame 83,
The frame 83 includes a plurality of small-diameter gears 84, a large-diameter gear 85 meshed and mounted between the small-diameter gears 84, and the like. A driving device (motor or the like) 86 provided on the 83 side is linked. The large-diameter gear 85 has a ring shape, and an inner hole thereof is formed as a rectangular hole 87 through which the square steel pipe 3 can be inserted.

The square steel pipe 3 is inserted into the large-diameter gear group 85 by moving the square steel pipe 3 in the axial direction of the pipe at this welding work site, or inserting the square steel pipe 3 at another location. The large-diameter gear group 85 is externally fitted, and the rectangular steel pipe 3 is transported by a crane or a forklift, and the large-diameter gear group 85 is mounted on the small-diameter gear 84 of each of the supporting portions 81 and 82 while meshing with each other. And so on.

As shown in FIGS. 12 and 13, each of the corners 3B of the square rectangular steel pipe 3 set as described above has through holes at the ends of a pair of flat plate portions 3A forming the corners 3B. 4 are formed (pierced) in the thickness direction. These through holes 4 are formed so as to communicate with the welding space X.

As shown in FIGS. 11 to 13, the welding site is equipped with a welding machine 90 and a backing device 94.
The welding machine 90 is an electroslag welding machine, an electrogas arc welding machine, or the like. The welding wire 91 is configured to be freely inserted from above into the through hole 4 in the vertical direction above the square steel pipe 3. A ground 92 is configured to be freely connected to a position apart from the rectangular steel pipe 3.

The backing device 94 comprises a frame 95,
Upward cylinder 96 provided on this frame 95
A piston rod 97 fitted inside the cylinder 96 so as to be able to move up and down, and a backing integrated with the upper end of the piston rod 97 and inserted from below into the vertical through hole 4 below the rectangular steel pipe 3. A material (asbestos, rock wool, or the like) 98 and a spring (elastic body) 99 for urging the backing material 98 in the insertion direction are provided. The mounting position of the backing device 94 can be freely changed.

Hereinafter, the welding operation will be described. With the rectangular steel tube 3 supported laterally on the support device 80, the driving device 86 is driven as necessary to rotate the rectangular steel tube 3 and adjust the phase of the inner diaphragm 40. In this state, FIGS. 12 and 13
As shown in FIG. 5, the welding Y between the inner diaphragm 40 and the two backing members 42 is performed on the inner surface 3a of the flat plate portion through the through holes 4 formed in the square steel pipe 3 and using the welding space X. The backing device 94 is set prior to the welding operation. That is, the set allows the backing material 98 to be inserted from below into the lower through-hole 4 formed corresponding to the welding equivalent portion,
It can be performed by moving and biasing the insertion direction in 99. At this time, the horizontal through hole 4 is closed by another backing material 98.

In this state, the welding wire 91 is inserted into the upper through-hole 4 of the rectangular steel pipe 3 from above and then inserted downward in the welding space X, so that an electro-slag welding machine or an electro-gas arc welding is performed. The welding Y of the inner diaphragm 40 and the two backing members 42 to the flat plate portion inner surface 3a can be sequentially performed from below to above by a machine or the like. At this time, the backing material 98 can prevent the molten metal from leaking downward or to the side from the through hole 4, and prevent the molten metal from leaking to the front and rear sides of the flat plate inner surface 3a by the above-described press-fitting connection. obtain.

The welding Y as described above is applied to the inner diaphragm 40.
On one side, and similarly on the other side. The welding Y may be performed simultaneously on both side edges. After the intended welding Y is performed on the left and right side edges in this manner, the welding Y between the upper edge side and the lower edge side is performed by moving the upper edge side and the lower edge side to both side edge sides. For this purpose, the rectangular steel pipe 3 is rotated by 90 degrees. The rotation of the rectangular steel pipe 3 is performed by synchronously driving the two drive support portions 81, so that the drive support portions 81 and the floating support portions can be rotated.
It can be done by being supported and guided by 82.

With the above, the operation of attaching the inner diaphragm 40 to the square steel pipe 3 is completed. The through holes 4 are filled by overlay welding or the like. As described above, for example, the column 100 shown in FIG. 14 is manufactured, and the beam member 101 is connected to the outside of the portion of the column 100 to which the diaphragm 40 is attached by welding Y.

Next, another embodiment of the present invention will be described with reference to FIG. That is, the inner diaphragm 40 is handled alone (one sheet). In this case, similarly to the above-described embodiment, the steel pipe 3 is supplied into the heated rectangular steel pipe 3 and integrated by cooling. Note that, with the same idea, three sheets (a plurality of sheets) can be handled as one set.

Next, still another embodiment of the present invention will be described.
This will be described with reference to FIGS. That is, in the above-described embodiment, the backing material outer surface 42a of the backing material 42 is a horizontal straight line, whereas in another embodiment shown in FIG. Material inclined outer surface 42b
In another embodiment shown in FIG. 17, a plurality of (two) ridges 42c are formed on the outer surface 42a of the backing material.
Or it is formed by one.

In another embodiment shown in FIG. 16, FIG.
As shown by the solid line, the inner diaphragm 40 can always be inserted smoothly and lightly by the guiding action of the backing member inclined outer surface 42b. Then, when the rectangular steel pipe 3 is cooled and contracted, the upper edge corners forming the backing material inclined outer surface 42b are easily cut into the flat plate inner surface 3a as shown by the imaginary line in FIG. The inner diaphragm 40 side is firmly connected to the square steel pipe 3.

In another embodiment shown in FIG.
As shown by the solid line in FIG. 17, since the gap S is formed between the ridge 42c and the flat plate portion inner surface 3a, the inner diaphragm 40 can be inserted without being caught or clogged. Then, the rectangular steel pipe 3 is cooled and contracted,
As shown by the phantom line in FIG. 17, the ridge 42c is
a, the inner diaphragm 40 side is firmly connected to the square steel pipe 3.

In the above-described embodiment, the inner diaphragm 40 is attached to the expanded rectangular steel pipe 5 immediately after being heated in the heating furnace 7 and hot formed. May be expanded by heating in a heating furnace provided near the site where the inner diaphragm is attached. In this case, the inner diaphragm supply device 50 may be inserted / extracted while being supported by the cart.

In the above embodiment, the square steel pipe 5
Is heated while being conveyed in the heating furnace 7 in the longitudinal direction, but may be heated while being conveyed in the transverse direction perpendicular to the longitudinal direction.

In the above embodiment, the square steel pipe 3
Is mainly ultra-thick large diameter steel pipe, the size of which is
For example, the thickness t is 16 to 60 mm and the material is SN400 B to SN
The outer diameter of 490B or SM520B is 450 to 850 mm. In this case, the gap S is formed to about 5 to 6 mm. Examples of the square steel pipe 3 include a one-seam square steel pipe formed by hot roll forming, a two-seam square steel pipe formed by butt-welding a pair of grooves formed by hot press forming.
Two-piece square steel pipes made by welding a pair of rolled grooves, two-seam square steel pipes made by rolling a pair of angled steel pieces facing each other, four-sided boxes, seamless steel pipes, etc. You.

In the above-described embodiment, the square steel pipe 3 having a square cross section is manufactured and the inner diaphragm 40 is attached. However, the rectangular steel pipe 3 having a rectangular cross section can be manufactured similarly and the inner diaphragm 40 can be attached. Things. By changing the arrangement of the rollers of the double-sided steel pipe forming mills 8 and 10, hot forming of a polygonal steel pipe such as a pentagonal steel pipe or a hexagonal steel pipe and mounting of the inner diaphragm 40 can be performed. Furthermore, a round shape is adopted as the steel pipe, and the inner diaphragm
40 may be attached.

In the above-described embodiment, the square steel pipe 3 on the cooling floor device 20 is provided with an inner diaphragm from one end thereof.
Although 40 is inserted, this is provided with an inner diaphragm supply device 50 etc. on each side of the cooling floor device 20,
The inner diaphragm 40 may be simultaneously inserted into the rectangular steel pipe 3 from both ends.

In the above-described embodiment, the inner diaphragm 40 is connected to the square steel pipe 3 on the cooling floor device 20. The floor device 25 may be omitted.

In the above-described embodiment, the inner diaphragm supply device 50 and the like are supported on the guide rail 70 side and synchronously moved on the endless path 71. This is because the inner diaphragm supply device 50 and the like are connected to the cooling floor device 20. One side may be deposited on the side or the square steel pipe 3 side and moved.

In the above-described embodiment, a cam mechanism or the like is used at the distal end operating portion of the inner diaphragm support device 60. According to this, since air, hydraulic pressure, and electricity are not used, it can sufficiently withstand the heating temperature and the like. Can be. However, a type using air, hydraulic pressure, or electricity provided with a heat resistant means may be used. The inner diaphragm 40 may be supported by an electromagnet.

In the above embodiment, the welding Y is performed by an electroslag welding machine or an electrogas arc welding machine. According to this, high-quality welding can be performed in a short time.

[0078]

According to the first aspect of the present invention, the inner diaphragm is caught or clogged by utilizing a sufficient gap generated between the outer surface of the backing material and the inner surface of the steel tube due to the thermal expansion of the steel tube. It can be easily and smoothly inserted without using. Then, the gap is automatically filled by the cooling shrinkage of the steel pipe, and the inner diaphragm side can be firmly connected to the steel pipe by utilizing the fact that the inner surface of the steel pipe abuts (presses) on the outer surface of the backing material. Therefore, the welding space can be formed in a sealed manner by the inner surface of the steel pipe, the inner diaphragm, and the backing material, and the welding of the inner diaphragm and the two backing materials to the inner surface of the steel pipe can be performed by using the molten metal on the inner surface of the front and back of the steel pipe or the inner diaphragm surface. It can always be performed well without leaking. Thus, the inner diaphragm can be attached to a desired position in the steel pipe without cutting the steel pipe.

According to the second aspect of the present invention,
The steel pipe can be made to have good properties by hot forming, and the inner diaphragm can be inserted by using the thermal expansion at the time of hot forming, and can be joined by using the cooling shrinkage. Therefore, the inner diaphragm can be attached efficiently and economically, as compared with a method in which a steel pipe at room temperature is heated and expanded from the beginning. Further, by inserting the inner diaphragm into the hot-formed steel pipe, the flow of air in the steel pipe during cooling can be reduced, and the steel pipe can be cooled with more uniform properties in all cross sections due to the heat retaining effect of air.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention and is a partially cutaway side view before an inner diaphragm is inserted in a method of attaching an inner diaphragm to a steel pipe.

FIG. 2 is a partially cutaway front view when the inner diaphragm is inserted in the method of attaching the inner diaphragm to the steel pipe.

FIG. 3 is a vertical sectional side view of a main part when the inner diaphragm is inserted in the method of attaching the inner diaphragm to the steel pipe.

FIG. 4 is a vertical sectional side view of a main part of the steel pipe in the middle of being pulled out in the method of attaching the inner diaphragm to the steel pipe.

FIG. 5 is a partially cutaway front view when the inner diaphragm support device is removed in the method of attaching the inner diaphragm to the steel pipe.

FIG. 6 is a process perspective view of a square steel pipe manufacturing facility in the method of attaching the inner diaphragm to the steel pipe.

FIG. 7 is a process explanatory view of a square steel pipe manufacturing facility in the method of attaching the inner diaphragm to the steel pipe.

FIG. 8 is a plan view of a cooling floor device portion of the steel pipe in the method of attaching the inner diaphragm to the steel pipe.

FIG. 9 is a vertical sectional front view of a cooling floor device of the steel pipe in the method of attaching the inner diaphragm to the steel pipe.

FIG. 10 is a side view of a cooling floor device portion of the steel pipe in the method of attaching the inner diaphragm to the steel pipe.

FIG. 11 is a side view of a welding work site in the method of attaching the inner diaphragm to the steel pipe.

FIG. 12 is a longitudinal sectional side view of a main part at the time of welding in the method of attaching the inner diaphragm to the inside of the steel pipe.

FIG. 13 is a partially cutaway front view at the time of welding in the method of attaching the inner diaphragm to the steel pipe.

FIG. 14 is a vertical cross-sectional view showing a state in which the beam is connected to the manufactured support.

FIG. 15 shows another embodiment of the present invention, and is a partially cutaway side view before an inner diaphragm is inserted in a method of attaching an inner diaphragm to a steel pipe.

FIG. 16 is a vertical cross-sectional side view of a main part when an inner diaphragm is inserted in a method for attaching the inner diaphragm according to still another embodiment of the present invention.

FIG. 17 is a longitudinal sectional side view of a main part when an inner diaphragm is inserted in a method of attaching the inner diaphragm according to a modification of still another embodiment of the present invention.

FIG. 18 is a longitudinal sectional view showing a conventional embodiment and showing a state in which a beam is connected to a column.

[Explanation of symbols]

 2 Polygonal hollow steel pipe 3 Square steel pipe (steel pipe) 3A Flat plate part 3a Flat plate part inner surface (steel pipe inner surface) 3B corner part 4 Through hole 7 Heating furnace 8 Front stage square tube forming mill 10 Rear stage square tube forming mill 20 Cooling floor unit 21 Chain conveyor device 25 Rear cooling floor device 40 Inner diaphragm 42 Backing material 42a Backing material outer surface 42b Backing material inclined outer surface 42c Protrusions 50 Inner diaphragm supply device 52 Arm rod 60 Inner diaphragm support device 65 Holder 71 Endless path 75 End straightening device 80 Supporting device 91 Welding wire 94 Backing device 98 Backing material A High temperature heating L Outside size of backing material S Gap X Welding space Y Welding W Inner width of square steel pipe 3 W + α Inner width of square steel pipe 3 when heated and expanded

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI // E04C3 / 32 E04C3 / 32 (JP, a) JP Akira 59-193777 (JP, a) JP flat 7-238636 (JP, a) JP Akira 49-113740 (JP, a) (58 ) investigated the field (Int.Cl. ⁷ , DB name) B23K 37/053

Claims (2)

(57) [Claims] An inner diaphragm integrated with a backing material is prepared, and the inner diaphragm is inserted to a predetermined position in the steel pipe that has been heated and expanded, and the inner surface of the steel pipe is backed by cooling and shrinking of the steel pipe. A method of attaching an inner diaphragm to a steel pipe, wherein the inner diaphragm is welded to an inner surface of the steel pipe, and then the inner diaphragm and a backing material are welded to the inner surface of the steel pipe. 2. The method for attaching an inner diaphragm to a steel pipe according to claim 1, wherein the inner diaphragm is inserted into a hot-formed steel pipe.