JP3308395B2 - Steel pipe joint and joint structure of steel pipe using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel pipe joint used for a frame of a power transmission tower or a steel pipe structure, and a joint structure of a steel pipe using the same.

[0002]

2. Description of the Related Art Conventionally, at a construction site of a power transmission tower or a steel pipe structure, as shown in FIG.
When the ends of the steel pipes 20 are joined to each other by welding joints 21, erection pieces 22 are attached to the outer surfaces of the ends of the two steel pipes 20 at equal intervals in the circumferential direction in advance in a factory, and the erection pieces 22 are opposed to each other at a construction site. Ends of both steel pipes 20 are temporarily attached to each other by bridging a splice plate 23 between the pieces 22. Next, the inside of the groove of the steel pipe joint is subjected to primary welding (welding for maintaining the tacked state until the splice plate 23 is removed and the entire circumference is welded). This welding was performed at a high place where the scaffold was poor, and the welding environment was poor and the work efficiency was poor. After the primary welding, the splice plate 23
And weld all around the groove. Thereafter, the erection piece 22 must be removed, and the removal mark must be finished smoothly with a grinder. Further, the steel pipe 20 to be used
Is thick, the end of the steel pipe 20 must be welded by multi-layer welding, and the welding management is very strict. Therefore, the efficiency of the steel pipe joining operation is poor, and the construction period of the power transmission tower and the steel pipe structure has been prolonged.

Therefore, conventionally, joints are provided at the ends of a pair of steel pipes facing each other, these joints are butted against each other, and a joint plate straddling each of these joints is attached to the joints.
It has been considered that the ends of both steel pipes are joined to each other by bolting the joint to the joint plate.

[0004] As for the method of providing the joint, there is a method of welding a mounting plate to an end of a steel pipe and providing a joint to the mounting plate, or a method of manufacturing by forging or the like and welding one side to an end of the steel pipe. There is a method in which a steel pipe joint having a base and a joint part provided on the other side of the base is manufactured in advance, and the base of the steel pipe joint is welded to an end of the steel pipe. In the former method, after the attachment plate is welded to the end of the steel pipe, an operation for providing a joint portion to the attachment plate is required one by one, so that the work efficiency is poor. For this reason, the latter method has recently been adopted in which it is only necessary to attach a steel pipe joint to the end of the steel pipe.

[0005] The steel pipe joint is provided with Japanese Utility Model Publication No. 1-128128.
Is described in Japanese Patent Application Publication No. This steel pipe joint is shown in FIG.
As shown in FIG. 2, a plurality of blade plates 25 (joint portions) are radially welded to one surface of a disk-shaped thick plate portion 24 (base portion) at right angles to the thick plate portion 24. When joining a pair of steel pipes 20 facing each other, the other surfaces of the thick plate portions 24 are welded to the ends of the steel pipes 20, respectively, and the blade plates 25 provided on one surface of the thick plate portions 24 are butted against each other. An end plate (joint plate) (not shown) straddling each of the blade plates 25 is attached to each of the blade plates 25, and the ends of the steel pipes 20 are joined to each other by fastening the blade plate 25 to the attached plate by bolts. .

[0006]

However, in the above-mentioned conventional steel pipe joint and the joint structure of the steel pipe using the same, a radial projecting portion 26 is formed on one surface of the thick plate portion 24, and these projecting portions are formed. 26, the blades 25 are attached to each other,
It is necessary to perform welding in a state where the center of the blade plate 25 is aligned with the center of the thick plate portion 24. As described above, since there are many welding points such as the welding point between the protruding portion 26 and the slat 25, and the welding direction is radial, the welding operation must be performed with great care so that welding defects do not occur. It is necessary to do it with work management. In addition, each of the blades 2
5 is attached only to the thick plate portion 2 during welding.
It is not easy to align the center of the slat 25 with the center of the slat 4. Therefore, the production efficiency of the steel pipe joint is poor, and the production cost is increased.

In the case where the center of the thick plate portion 24 is not aligned with the center of the blade plate 25 due to a manufacturing error of the steel pipe joint, the thick plate portion 24 is attached to the end of the steel pipe 20, and the blade plate 25 and the blade plate 25 are straddled. When the ends of the steel pipes 20 are joined to each other by bolting with the attached plate, misalignment occurs between the steel pipes 20, and as a result, transmission of the load between the steel pipes 20 is uncertain. Become.

The present invention has been made to solve the above problems, and a first object of the present invention is to enable a steel pipe joint to be manufactured with high accuracy.

A second object of the present invention is to facilitate assembly and construction and to smoothly transmit a load.

[0010]

In order to achieve the above object, the present invention comprises a substantially cylindrical base which is welded on one side to an end of a steel pipe. Connecting a connecting cylinder to the center of the base via a radial connecting plate in a concentric manner, and extending the connecting cylinder and the connecting plate to the opposite side of the steel pipe side, The extending part of the part is a joint part.

According to a second aspect of the present invention, the ends of a pair of steel pipes are arranged to face each other, and one end of each of the substantially cylindrical bases is welded to the ends of the steel pipes. Joining and connecting the connecting cylinders concentrically to the center of the base via respective radial connecting plate portions, and extending the connecting cylinder and the connecting plate portions to the side where they abut each other, The extending portion of the connecting plate portion is a joint portion, these joint portions are butted against each other, and a joint plate straddling the joint portion is attached to both joint portions,
The joint portions are each bolted to the joint plate.

[0012]

According to the structure of the first aspect of the present invention, the extension of the radial connecting plate portion in which the connecting cylinder is concentrically connected to the center of the base is the joint, and the center of the joint is the base. The center of the joint is aligned with the center of the end of the steel pipe when the base is welded to the end of the steel pipe.

According to the construction of the second aspect, in the assembling operation, the ends of the pair of steel pipes are arranged to face each other, and the bases are respectively welded to the ends of the steel pipes by full circumference welding or the like. The joint portions are butted against each other, a joint plate straddling the joint portions is attached to each joint portion, and the joint portion is bolted to the joint plate. In this case, the extending portion of the radial connecting plate portion in which the connecting tubular body is concentrically connected to the center of the base portion is used as the joint portion, and the center of the joint portion is the center of the base portion, and thus the end of the steel pipe provided with the base portion. The two steel pipes are joined concentrically to match the center of the part.

In such a joint structure of a steel pipe, the transmission of a load from one steel pipe to the other steel pipe is performed by a steel pipe joint (a base, a connecting cylinder, a connecting plate, and a joint) on one steel pipe.
And the joint plate and the steel pipe joint on the other steel pipe side (base, connecting cylinder,
(A connecting plate portion and a joint portion). In this case, it is possible to make the entire cross section of the base portion, the connecting cylinder, and the connecting plate portion on the steel pipe joining side, and the entire cross section of the connecting tubular body, the joint portion, and the joint plate on the bolt joint portion side substantially the same. is there. When the cross sections are substantially the same, the axial force is smoothly transmitted from one steel pipe to the other steel pipe via the steel pipe joint and the joint plate.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a joint structure of a steel pipe according to one embodiment of the present invention, FIG. 2 (1) is a side view taken along the arrow P in FIG. 1, and (2) is an AA in (1). 3 is a cross-sectional view taken along the line BB of FIG. 2 (2), and FIG. 4 is a cross-sectional view corresponding to FIG. 3 showing a modification of the joint structure of the steel pipe.

The joint structure of a steel pipe is such that a pair of steel pipes 1 and 2 are arranged to face each other, steel pipe joints 3 and 4 are respectively attached to ends of the steel pipes 1 and 2, and these steel pipe joints 3 and 4 are connected to a joint plate. 5
And a cylindrical cover member 6
Covered by

Since the steel pipe joints 3 and 4 have the same structure, the structure of only one steel pipe joint 3 will be described. The steel pipe joint 3 has a substantially cylindrical shape having one side welded to the end of the steel pipe 1. The base 7 is shaped. A connecting cylinder 8 is concentrically connected to the center of the base 7 via a radial connecting plate 9. The connecting cylinder 8 and the connecting plate 9 extend on the side opposite to the steel pipe 1, and the extending portion of the connecting plate 9 is a joint 10. A bolt hole 11 is formed in the radial joint portion 10. Reference numeral 12 denotes an opening formed between the connecting plate portions 9. The steel pipe joints 3 and 4 are integrally made of cast steel in order to improve the manufacturability, and the bolt holes 11 are formed after the manufacture. The diameter of the connecting cylinder 8 is appropriately set in a state where the required size of the joint portion 10 is secured. For example, as shown in FIG. 3, the connecting cylinder 8 may be formed to have a large diameter. Needless to say.

The steel pipe joints 3 and 4 are manufactured by casting. Due to the structure of the steel pipe joints 3 and 4, it is possible to make the thickness of each component (the base 7, the connecting cylinder 8, the connecting plate 9, the joint 10) the same. If the steel pipe joints 3 and 4 are manufactured by casting with the same thickness, it is possible to prevent stress concentration and uneven heat shrinkage caused by a change in the thickness of the steel pipe joints.
4 is obtained.

The joint structure of the steel pipe is assembled using the steel pipe joints 3 and 4 as follows. That is, one end of the base 7 of each of the steel pipe joints 3 and 4 is joined to the end of each of the steel pipes 1 and 2 by full-circumferential welding, and the center of the base 7 is connected to the center of the base 7 via the radial connecting plate 9. The connecting cylinder 8 is concentrically connected. The connecting cylinder 8 and the connecting plate 9 extend to the side where the steel pipes 1 and 2 abut each other, and the extending portions of the connecting plate 9 are joints 10, respectively. A bolt hole 11 is formed in each of the joint portions 10 by drilling, and a bolt hole 14 is formed in each of the joint plates 5 to which the joint portions 10 are joined. Then, the facing joint portion 1
0, one side of the joint plate 5 is in contact with one joint portion 10, and the other side of the joint plate 5 is in contact with the other joint portion 10. After placing,
A high-strength bolt 15 is inserted into the bolt hole 14 of the joint plate 5 and the bolt hole 11 of the joint portion 10, and a nut 16 is screwed into the high-strength bolt 15 to tighten the joint portion 10 and the joint plate 5. Bolts are fastened.

A cover member 6 for improving the appearance of the steel pipe is provided between the bases 7 in the joint structure of the steel pipe. The cover member 6 covers the joint portion 10 and the joint plate 5 constituting the bolt joint portion. ing. This cover member 6
Has a split structure, and is composed of two divided bodies 6a and 6b having an arc-shaped cross section. After assembling the joint structure of the steel pipe, the cover member 6 is interposed between the bases 7 and arranged to face each other, assembled by sealing bead welding, and joined to the base 7 by sealing bead welding. The cover member 6 does not participate in transmitting the load at all.

In the above configuration, the extending portion of the radial connecting plate 9 in which the connecting tubular body 8 is concentrically connected to the center of the base 7 of the steel pipe joints 3 and 4 is defined as the joint 10, and The center is aligned with the center of the base 7, and the base 7 is
The center of the joint 10 is aligned with the center of the end of each of the steel pipes 1 and 2 when it is welded to the end of the pipe 2.

When assembling and using the steel pipe joints 3 and 4 at a construction site of a power transmission tower or a steel pipe structure, a pair of steel pipes 1 and 2 constituting a framework of the structure are used.
Of these, the steel pipe joints 3 are welded to both ends of the steel pipe 1 and the steel pipe joints 4 are welded to both ends of the steel pipe 2, and then the steel pipes 1 and 2 are hot-dip galvanized. When galvanizing the steel pipe 1 to which the steel pipe joint 3 is attached,
The steel pipe 1 is immersed in the hot dip galvanizing solution in the plating tank while being tilted, and is taken out again after the plating is completed. At this time, since the air inside the steel pipe 1 is discharged to the outside through the opening 12 of the steel pipe joint 3 attached to the upper end of the steel pipe 1, the opening of the steel pipe joint 3 attached to the lower end of the steel pipe 1 is opened. The hot-dip galvanizing solution flows into and out of the steel pipe 1 through the part 12. Thus, the steel pipe joint 3 and the steel pipe 1 are hot-dip galvanized.

The same applies to the case where hot dip galvanization is applied to the steel pipe 2 to which the steel pipe joint 4 is attached, and the hot dip galvanization is applied to the steel pipe joint 4 and the steel pipe 2.

In the steel pipe joints 3 and 4 configured as described above, each component can have the same thickness. When the plate thickness is the same, the respective heating temperatures become the same, so that the plating time can be shortened and the plating operation can be performed efficiently. In addition, due to the configuration of the steel pipe joints 3 and 4,
It is possible to prevent an extremely large thickness difference between the welded joint between the base 7 of the steel pipe 1 and the end of the steel pipe 1 and the welded joint between the base 7 of the steel pipe joint 4 and the end of the steel pipe 2. Cracks do not occur in the weld during galvanization.

In the assembling work, the ends of the steel pipes 1 and 2 are arranged to face each other, and the joints 10 of the steel pipe joints 3 and 4 provided at the ends of the steel pipes 1 and 2 are abutted against each other. This is performed by attaching a joint plate 5 straddling each of the joints 10 to the joint 10 and fastening the joint 10 to the joint plate 5 with bolts.

In the joint structure of the steel pipe obtained in this manner, the radial connecting plate 9 having the connecting cylinders 8 concentrically connected to the center of the base 7 of the steel pipe joints 3 and 4 respectively extends. The joint is a joint 10 and the center of the joint 10 is aligned with the center of the base 7 and the center of the ends of the steel pipes 1 and 2 provided with these bases 7, respectively. They will be joined concentrically.

The transmission of the load from one steel pipe 1 to the other steel pipe 2 is sequentially performed via the steel pipe joint 3 and the joint plate 5 on the steel pipe 1 side and the steel pipe joint 4 on the steel pipe 2 side. In this case, the entire cross section of the base 7, the connection cylinder 8 and the connection plate 9 on the steel pipe joining side, and the entire cross section of the connection cylinder 8, the joint 10 and the joint plate 5 on the bolt joint side are substantially the same. It is possible to
In the case of substantially the same cross section, a power transmission tower or a steel pipe structure constructed by connecting the steel pipes 1 and 2 via the steel pipe joints 3 and 4 and the joint plate 5 is subjected to an external force such as an overhead load or wind force. When an axial force acts on the steel pipes 1 and 2, the axial force is smoothly transmitted from one steel pipe 1 to the other steel pipe 2 via the steel pipe joints 3 and 4 and the joint plate 5.

In the above embodiment, the case where the steel pipes 1 and 2 are joined using the steel pipe joints 3 and 4 as the joint structure of the steel pipe has been described. Also, the present invention may be applied to a case where the gusset plate 18 is joined to the gusset plate 18 provided in the above.

In this joint structure of a steel pipe, the transmission of the load between the one steel pipe 1 and the other steel pipe 17 or the like is performed by the steel pipe joint 3 (the base 7, the connecting cylinder 8, the connecting pipe 8, and the connecting pipe 8) on the one steel pipe 1 side. This is sequentially performed through the plate portion 9 and the joint portion 10), the joint plate 5, and the gusset plate 18 on the other steel pipe 17 and the like side. In this case, the entire cross section of the base 7, the connection cylinder 8 and the connection plate 9 on the steel pipe joining side, and the entire cross section of the connection cylinder 8, the joint 10 and the joint plate 5 on the bolt joint side are substantially the same. It is possible to When the cross sections are substantially the same, the axial force is smoothly transmitted from one steel pipe 1 to the other steel pipe 17 via the steel pipe joint 3, the joint plate 5, and the gusset plate 18.

[0031]

As described above, according to the present invention, according to the first aspect, the connecting cylinder is concentrically connected to the center of the base via the radial connecting plate portion, and the connecting cylinder is provided. It is possible to manufacture a high-precision steel pipe joint in which the center of the joint portion provided on the outer peripheral portion of the steel pipe matches the center of the base portion. This steel pipe joint can be made to have the same thickness of its component parts, and if the same thickness is used, it prevents stress concentration and uneven heat shrinkage caused by changes in the thickness during casting. As a result, integrated production by casting can be performed, so that production efficiency can be improved, production accuracy can be improved, and production cost can be reduced as compared with the related art. Further, when the base of the steel pipe joint is welded to the end of the steel pipe, the center of the joint coincides with the center of the end of the steel pipe, so that the joint structure of the steel pipe is effectively assembled.

Further, according to the present invention, in the second aspect of the present invention, the bases are welded to the ends of the pair of opposed steel pipes by full circumference welding or the like to butt the joints to each other, and the joints are respectively joined to the joints. By assembling the joint plate straddling this and bolting the joint portion to the joint plate, assembly and construction can be easily performed. At that time, the center of each joint portion is located at the center of the end of the steel pipe. Since they match, the steel pipes can be easily joined to each other without causing misalignment as in the related art. Therefore, the efficiency of assembly and construction can be improved as compared with the related art.

Further, it is preferable that the cross section of the base, the connecting cylinder and the connecting plate on the steel pipe joining side and the cross section of the connecting cylinder, the joint and the joint plate on the bolt joint side are substantially the same. If it is possible to make the sections substantially the same, the axial force can be smoothly transmitted from one steel pipe to the other steel pipe via the steel pipe joint and the joint plate.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a joint structure of a steel pipe according to an embodiment of the present invention.

FIG. 2A is a side view of FIG. (2) It is a longitudinal cross-sectional view which follows the AA line of (1).

FIG. 3 is a sectional view taken along line BB of FIG. 2 (2).

FIG. 4 is a sectional view corresponding to FIG. 3, showing a modification of the joint structure of the steel pipe.

FIG. 5 (1) is a front view showing a joint structure of a steel pipe according to another embodiment of the present invention. (2) It is sectional drawing which follows CC line of (1).

FIG. 6 (1) is a front view showing a joint structure of a conventional steel pipe. (2) It is sectional drawing which follows the DD line of (1).

FIG. 7 (1) is a left side view showing the joint structure of another conventional steel pipe. (2) It is a longitudinal cross-sectional view which follows the EE line of (1).

[Explanation of symbols]

 1, 2 steel pipe 3, 4 steel pipe joint 5 joint plate 6 cover member 7 base 8 connecting cylinder 9 connecting plate part 10 joint part 11 bolt hole 14 bolt hole 15 high strength bolt 16 nut

Claims (3)

(57) [Claims] 1. A base having a substantially cylindrical base which is welded and joined to an end of a steel pipe on one side, and a connecting cylinder body is concentrically connected to a center of the base via a radial connecting plate, A steel pipe joint, wherein a connecting cylinder and a connecting plate portion are extended to a side opposite to the steel pipe side, and an extending portion of the connecting plate portion is a joint portion. 2. A pair of steel pipes are arranged with their ends facing each other, one end of each of the substantially cylindrical bases is welded to each of the ends of the steel pipes, and a radial connecting plate is formed at the center of the base. The connecting cylinders are connected concentrically through the connecting cylinder, and the connecting cylinder and the connecting plate are respectively extended to the side where they abut each other, and the extending portion of the connecting plate is used as a joint. Butted against each other, a joint plate straddling each of these joints is attached to both joints,
A joint structure for steel pipes, wherein the joints are bolted to the joint plate. 3. The joint structure for a steel pipe according to claim 2, wherein a tubular cover member for covering the joint portion and the joint plate is attached between the base portions .