JPH02112892A - Apparatus for producing electric resistance welded tube - Google Patents

Abstract

PURPOSE:To eliminate the spacing between joint surfaces of the pipe by adjusting the angle of grinders provided to both side parts of a steel strip and forming slopes having joint surfaces in the axial center direction to the end parts of the steel strip before a stage for forming the open pipe. CONSTITUTION:The grinders 2a of the grinding devices 2 installed to both side parts of the steel strip W before the stage for forming the open pipe grind the joint surfaces Wa. Angle adjusters 4 adjust the inclination of the grinders 2a and form the slopes Wa so as to form the joint surfaces b in the axial center direction of the open pipe (a). The steel strip W is supplied to the pipe forming device at this time to form the open pipe (a) and the joint part (b) is joined by welding to form the pipe. Since the slopes Wa are formed, the spacing by the thickness of the steel strip W generated in the joint part (b) is eliminated and the effective and adequate welding is executed. The quality is thus improved.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Field of Application) The present invention is directed to, for example, a steel strip having a thickness of about 2.3 mm to about 5.0 mm and an outer diameter of about 50 (to) to 80 cm. The present invention relates to an electric resistance welded steel pipe manufacturing apparatus that continuously manufactures electric resistance welded steel pipes by forming open pipes and welding joints (II) of the open pipes.

(Prior art) Generally, electric resistance welded steel pipes are manufactured by continuously forming a steel strip into a cylindrical shape using a group of forming rolls to form an open pipe, and then joining the joints of this open pipe by welding. .

The electric resistance welded steel pipe manufacturing equipment for this pillar, which has already been proposed, is the fourth
It is constructed as shown in Figures (A) and (B) and Figure 5.

That is, in FIGS. 4(A) and 5, the coiled steel strip that is the material of the ERW steel pipe is unwound by being inserted into the unwinding device, and then the coiled steel strip is unwound. Next, this is continuously fed to a pipe forming device to form an open pipe, and after that, the joints of this open pipe are welded and joined using a seam welding device, and then this is cut into a predetermined shape using a pipe end cutting device. Finally, a test and inspection device is used to inspect the welded portions of the oven vibe and whether it has been formed to a predetermined outer diameter.

(Problems to be Solved by the Invention) However, the above-mentioned electric resistance welded steel pipe manufacturing apparatus is difficult to solve as shown in FIG.
As shown in A), a gap C is formed between the joints of the open pipe a due to the thickness of the steel strip, and as the thickness of the steel strip increases, the gap C between the joints increases. This spreads, making it difficult to form the welded part of the open pipe to a predetermined outer diameter, and as shown in FIG. There are drawbacks such as the risk of forming an outwardly protruding edge portion d on jb.

The present invention has been made in view of the above-mentioned circumstances, and the present invention connects the open pipe by grinding and forming slopes on both ends of the open pipe, the joint surfaces being in the axial direction of the open pipe. It is an object of the present invention to provide an electric resistance welded pipe manufacturing apparatus which eliminates the gap caused by the thickness of the steel band at the section and effectively and appropriately welds the joint section of the open pipe to improve quality.

[Structure of the invention]

(Means for Solving the Problems and Their Effects) The present invention provides an electric resistance welded pipe manufacturing apparatus that uses steel strips to form pipes, in which a conveyance path for the steel strips is provided before the step of forming open pipes.
Grinding devices are provided on both sides of the steel strip, each angle adjustment device is connected to each grinding device, and the grinder of each of the grinding devices is connected to each end of the steel strip by each angle adjustment device. Each inclined surface with the axial direction of the open pipe as the joint surface is ground and formed, and the gap due to the thickness of the steel strip is eliminated at the joint of the open pipe, and the joint of the open pipe is appropriately welded. This is to improve quality.

(Example) Hereinafter, the present invention will be described with reference to an illustrated embodiment.

Note that the present invention includes the same constituent members as those in the above-mentioned specific example.
The same reference numerals will be used for explanation.

In FIG. 1, reference numeral 1 denotes a conveyance path for the steel strip W before the tube forming process of an open pipe in an electric resistance welded pipe manufacturing apparatus that uses a steel band to form a tube. At positions on both sides of the steel strip W, each grinding device 2 is provided so as to be driven by each drive motor 3, and each grinder 2a of this grinding device 2 is provided on both sides of the steel strip W. It is provided so as to form by grinding the joining surface Wa which is inclined to . Further, each angle adjusting device 4 such as a cylinder device is connected to each of the grinding devices 2, and each angle adjusting device 4 connects each grinder 2a of each of the grinding devices 2 to both sides of the band fv4W. Each inclined surface Wa whose joint surface is in the axial direction of the open pipe a is formed by grinding.

Therefore, in FIG. 3, the coiled steel strip W, which is the material for the electric resistance welded steel pipe, is inserted into the unwinding device.
The coiled steel strip W is unwound, and then each grinder 2a of each grinding device 2 is joined to both sides of the steel strip W in the axial direction of the open pipe a using each angle adjustment device 4. Each inclined surface Wa to be faced is formed. Furthermore, each of the grinders 2a of each of the grinding devices 2 grinds and forms each inclined surface Wa on both sides of the steel strip W. Next, the steel strip W with each inclined surface Wa formed by grinding is continuously supplied to a pipe forming apparatus to form an open pipe a. After that, the joint part of this open pipe a is welded and joined, and then it is cut to a predetermined length with a pipe end cutting device, and finally, this is cut into the above-mentioned open pipe with a testing and inspection device. Inspect the welded part Wa of the pipe a and whether it is formed to a predetermined outer diameter.

Next, the present invention will be explained using mathematical formulas.

That is, each angle adjusting device 4 forms each inclined surface Wa on both sides of the steel strip W with each grinder 2a of each of the grinding devices 2 having the axial direction of the open pipe a as the joining surface. Furthermore, each grinder 2a of each of the above-mentioned grinding devices 2
Each inclined surface Wa is formed by grinding at each end Wa. The grinding angle θ at this time is as shown in the above-mentioned open pipe a shown in FIG. 2, so the grinding angle θ SmK(πDo−πD1)/2 However, K can be calculated using the angle conversion constant formula.

At this time, the grinding angle θ is automatically controlled by an angle adjustment control device (not shown) based on data such as the width of the steel band W and the desired diameter of the oven coil.

〔Effect of the invention〕

As described above, according to the present invention, in the electric resistance welded pipe manufacturing apparatus for pipe forming using band steel W, the open pipe a
This steel strip W is placed on the conveyance path of the steel strip W before the pipe forming process.
Each grinding device 2 is provided on both sides of the steel strip W, each angle adjusting device 4 is connected to each grinding device 2, and each angle adjusting device 4 controls the grinder 2a of each grinding device 2 on both sides of the steel strip W. Since each inclined surface Wa whose joint surface is in the axial direction of the open pipe a is formed by grinding at the joint part, the gap caused by the thickness of the steel strip W at the joint part of the open pipe a can be eliminated. Not only can the joints of the open pipe a be effectively and appropriately welded, but also the quality can be improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the main parts of the electric resistance welded steel pipe manufacturing apparatus of the present invention, FIG. 2 is a cross-sectional view of an electric resistance welded steel pipe formed by the electric resistance welded steel pipe manufacturing apparatus of the present invention, and FIG. A block diagram for explaining the operation of the electric resistance welded steel pipe manufacturing apparatus of the present invention, FIG. 4(A)
(B) is each cross-sectional view for explaining an ERW steel pipe formed by an already proposed ERW steel pipe manufacturing apparatus, and FIG.
FIG. 2 is a block diagram for explaining the operation of an already proposed electric resistance welded steel pipe manufacturing apparatus. DESCRIPTION OF SYMBOLS 1... Conveyance path, 2... Grinding device, 2a... Grinder, 3... Drive motor, 4... Angle adjustment device. Applicant's agent Mr. Sato Figure 1 (A) (B) Figure 4 Figure 2 Figure 3 Figure 5

Claims (1)

[Claims] In the electric resistance welded pipe manufacturing equipment that uses strip steel to form pipes,
The conveyance path of the steel strip before the open pipe forming process includes grinding devices located on both sides of the steel strip and angle adjustment devices connected to the grinding devices. , wherein each of the angle adjustment devices is configured to use a grinder of each of the above-mentioned grinding devices to form by grinding each inclined surface on each end of the above-mentioned steel strip with the axial direction of the above-mentioned open pipe serving as a joint surface. Sewn steel pipe manufacturing equipment.