JP2000051946A - Steel tube correction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device to correct bending and true roundness defects generated in a steel tube, etc., used for a structural steel tube column. SOLUTION: The steel tube correction device is provided with a transfer roller means, which is arranged at a front/rear of a steel tube correction press and makes plural transfer rollers 25 retractable with respect to a steel tube transfer line, and a bending correction support base 21 and a position change means, both arranged between the transfer rollers 25, which changes circumferential direction position of a steel tube. Further, in the device, the position change means is provided with a pair of rollers 26, 26 rotating in the face orthogonal to the transfer line arranged so as to be retractable above/below the transfer line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to bending and poor roundness of welded steel pipes, particularly line pipes for pipelines for transporting oil, natural gas, etc., and steel pipes used as steel pipe columns for structures. And a device for correcting the

[0002]

2. Description of the Related Art In a tube forming process of a welded steel pipe, for example, a UOE system, after welding, the pipe is expanded and subjected to various inspections to produce a product. In this inspection, a bend (in the direction of the tube axis) or a locally inferior roundness is extracted and corrected.

[0003] These correction methods will be described with reference to Figs. Correction of bending: The press 10 includes an upper mold 4 and a lower mold 5 each having a sectional shape shown in FIG.
It is attached to. The pipe support 7 is fixed at an appropriate position on the left and right of the press 10 in accordance with the length of the steel pipe 8 to be bent. At this time, the receiving surface of the tube support 7 is set to a higher level than the receiving surface of the lower mold 5 in accordance with the amount of bending of the tube. The steel pipe 8 is inserted by means of a ceiling crane or the like so that the point of maximum bending is below the upper mold, and the hanging wire is unwound and both ends of the steel pipe 8 are supported by the pipe support 7. The slide is lowered to correct the bending of the steel pipe 8.

[0004] Correction of local roundness: In this case, a mold 5 which is an upper mold 4 attached to a receiving surface of a shim 4a shown in FIG.
Is installed. The thickness of the shim 4a is determined according to the ratio of the major axis to the minor axis. The steel pipe 8 is hung by a ceiling crane or the like, inserted between the two dies 4 and 5, positioned so that the top of the major axis is in the vertical direction, and lowered to correct the upper die 4.

[0005]

However, the above-mentioned conventional method has the following problems.

If it is desired to perform both bending correction and roundness correction with a single press, it takes a long time to set up and remove the tube support.

[0007] The taking in of the steel pipe into the press machine, taking it out of the machine, and changing the position of the steel pipe during the straightening operation must be carried out while hanging it with a crane or a lifting machine. It is necessary to touch the steel pipe as it is, and there is a safety problem.

[0008] It is necessary to rotate the steel pipe in order to change the pressing position at the time of straightening, but this rotating operation requires considerable labor.

[0009]

The present invention solves the above problems.
The following device solves the problem.

[0010] The first device comprises, on each of a front surface and a rear surface of a steel pipe straightening press, a conveying roller means for allowing a conveying roller to protrude and retract from a steel pipe conveying line, and a bending straightening support for supporting the steel pipe during straightening. A table and a position changing means capable of moving in and out of the transfer line and changing a circumferential position of the steel pipe are provided.

[0011] According to this apparatus, there is no setup work such as installation and removal of the bending straightening support necessary for the straightening work of the steel pipe, and the straightening work time can be greatly reduced. Also,
There is no heavy muscle work involved in the setup.

The second device is a device in which the position changing means of the first device is provided with a pair of rollers having a rotation axis parallel to the transport line so as to be able to protrude and retract above and below the transport line.

According to this device, the straightened portion of the steel pipe can be properly and easily aligned with the mold.

[0014] A third device is a transportation device of the first device, wherein the transportation roller means comprises a column erected on the floor, a transportation roller mounting frame having one end pivotally mounted on an upper end of the column, A fluid cylinder having a rod end pivotally connected to the other end of the transfer roller mounting frame and the other end pivotally mounted on the floor, and a transfer roller pivotally supported on the transfer roller mounting frame. It is made up of

According to this apparatus, the transport roller can be easily evacuated to a position where it does not hinder the work prior to the correction work.

In the fourth device, the bending correction support of the first device is composed of a fluid cylinder erected on the floor and a cradle attached to the rod end of the fluid cylinder.

According to this device, even if the size of the steel pipe or the degree of bending thereof changes, the position of the cradle can be easily changed in accordance with the change.

[0018]

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

FIG. 1 is a side view of a steel pipe straightening apparatus according to the present invention, and FIG. 2 is a view taken in the direction of arrows AA in FIG. Steel pipe straightening press 10
Is composed of frames 2 and 2 erected on the floor in front and behind, sliding means and bolster means. The slide means includes a slide elevating device 1 installed on the frame, a slide 3 moving up and down along the frames 2 and 2 by the elevating device, and an upper die attached to the lower surface of the slide 3. 4. The bolster means includes a lower mold 5, a bolster 6 to which the lower mold 5 is attached, and a bolster 6
And a pair of fluid cylinders 11a and 11b for moving the bolster 6 left and right.

Before and after the steel pipe straightening press 10, a steel pipe for straightening is bent and a straightening support 21 is provided. A pair of conveying roller means having a conveying roller at the upper part and a pair of pressing means for changing the pressing position of the steel pipe. Position changing means having a receiving roller is provided. The height of the bending correction support base 21 can be changed. The transport roller means includes a support column 23 erected on the floor, and a transport roller mounting frame having one end pivotally mounted on the upper end of the support column 23 and the other end pivotally mounted on the rod end of the fluid cylinder 24. And a transfer roller 25 and a fluid cylinder 24 supported by the mounting frame 25a. This fluid cylinder-24
Is pivotally attached to a bracket (not shown) on the floor. Therefore, the transport roller 25 can be held at the transport level or below the transport level by expanding and contracting the rod of the fluid cylinder 24.

The position changing means includes a pair of fluid cylinders 27 erected on the floor and a pair of shafts supported at the upper ends of rods of the fluid cylinders 27 so as to rotate in the left-right direction via a mounting base. Rollers 26, 26 are provided. The pair of rollers can be rotated forward and backward by driving means (not shown).
In addition, instead of the fluid cylinder 27, a screw rod
A nut mechanism can be used.

With the above configuration, the steel pipe straightening apparatus of the present invention can easily and easily correct the bending and roundness of a steel pipe in a short time.

First, a method for straightening a steel pipe will be described. (1) In FIG. 1, the steel pipe to be straightened is transported from the conveyor roller 25 behind the steel pipe straightening press 10 using a ceiling crane or the like.
Put on top of 25. (2) The conveyor roller 25 is driven to rotate to move the steel pipe, and the straightening portion is positioned between the upper mold 4 and the lower mold 5 of the steel pipe straightening press. (3) In the positioning of (2), when the top of the peak of the steel pipe to be pressed by the upper mold 4 is not aligned, the steel pipe is moved by the rollers 26, 26 of the front and rear position changing means. The position is changed so that the top is directly below the upper mold 4. (4) As shown in FIG. 3, the transport rollers 25 of the transport roller means before and after the steel pipe straightening press 10 are lowered, and are supported by the bent pipe straightening supports 21 and 21. (5) Press the top of the mountain of the steel pipe while lowering the upper mold 4 to correct the bending of the steel pipe.

If the bending of the steel pipe cannot be completely corrected in the above steps, the steps (3) to (5) are repeatedly performed.

Next, a method of correcting a deformed steel pipe to a perfect circle will be described. Since the steps (1) and (2) are the same as the above-described bending correction, the step (3) and subsequent steps will be described. (3) In this case, the upper mold 4 is provided with a liner
4a is used. Position to be pressed: Positioning is performed using the roller 26 of the position changing means so that the part deformed convexly becomes the center of the upper mold 4. (4) The straightening portion of the steel pipe is pressed while the upper mold 4 is lowered, and straightening is performed. In order to obtain a steel pipe having a roundness, it is often not possible to correct it with only one pressing. In such a case, the pressing correction is performed several times while gradually changing the pressing position by using the roller 26 of the position changing means. FIG. 5 shows this state.

FIG. 6 shows how the straightened steel pipe 8 is paid out. (1) First, the transport 25 before and after the steel pipe straightening press 10 is raised to the transport level, and the bending straightening support 21 is raised.
And the roller 26 of the position changing means is lowered below the transport level. (2) The transport rollers 25 to 25 are driven to pay out the steel pipe 8 to the outside of the machine.

[0027]

According to the present invention, the following effects can be obtained. (1) The conventional setup work required for steel pipe straightening work is eliminated, so that the straightening time can be greatly reduced, and heavy muscle work involved in the setup work is completely eliminated. (2) The straightened portion of the steel pipe can be properly and easily aligned with the mold. (3) The transport roller can be evacuated to a position that does not hinder the operation before the correction operation. (4) It is possible to easily change the position of the support of the bending correction support base to a position corresponding to the size of the steel pipe or the degree of bending thereof.

[Brief description of the drawings]

FIG. 1 is a side view of a steel pipe straightening apparatus according to the present invention.

FIG. 2 is a view taken along the line AA of FIG. 1;

FIG. 3 is a side view illustrating the straightening of a steel pipe according to the present invention.

FIG. 4 is a side view showing a state in which a circumferential direction of a steel pipe to be straightened according to the present invention is changed.

FIG. 5 is a side view showing a state in which a distorted steel pipe according to the present invention is corrected to a perfect circle.

FIG. 6 is a side view showing a state in which the steel pipe according to the present invention is dispensed from a steel pipe straightening press.

FIG. 7 is a side view showing a conventional steel pipe straightening method.

FIG. 8 is a front view showing an upper mold and a lower mold.

FIG. 9 is a side view showing a state of alignment at the time of bending correction of a conventional steel pipe.

FIG. 10 is a front view showing a mold to which a shim is attached for correcting the roundness of a local portion of a steel pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Steel pipe straightening press 1 Slide elevating device 2 Frame 3 Slide 4 Upper die 5 Lower die 6 Bolster 8 Steel pipe 11a, 11b, 12, 24, 27 Fluid cylinder-21 Bending straightening support stand 23 Post 25 Transport roller 25a Transport roller mounting frame 26 Roller

Claims (4)

[Claims] 1. A transfer roller means for allowing a transfer roller to protrude and retract from a transfer line for a steel pipe on each of a front surface and a rear surface of a steel tube straightening press; a bending straightening support table for supporting the steel tube during straightening; A steel pipe straightening device, comprising: a position changing means capable of moving in and out of a transfer line and changing a circumferential position of the steel pipe. 2. The steel pipe straightening apparatus according to claim 1, wherein said position changing means is a means provided with a pair of rollers having a rotation axis parallel to the transport line so as to be able to protrude and retract above and below the transport line. 3. The transport roller means according to claim 1, wherein said transport roller means comprises a column standing on the floor, a transport roller mounting frame having one end pivotally connected to an upper end of said column, and said transport roller. A fluid cylinder having a rod tip pivotally attached to the other end of the roller mounting frame and the other end pivotally mounted on the floor; and a transport roller pivotally supported on the transport roller mounting frame. Become a steel pipe straightening device. 4. The steel pipe straightening device according to claim 1, wherein the bending straightening support comprises a fluid cylinder erected on the floor and a pedestal attached to a tip of a rod of the fluid cylinder.