JPS60111719A - Formation of square metallic blank pipe having embossed pattern - Google Patents

Abstract

PURPOSE:To speed up the production of a titled blank pipe by embossing a steel strip and bending its edge at the same time and performing loop control and the synchronous control of both driving systems between the stands of embossing roll and forming roll. CONSTITUTION:In case of roll-forming embossing patterns in a steel strip 11, roll calibers 27-1 having each a fixed radius R of curvature are added to upper and lower rolls 14-1, 14-2 provided with female and male dies 25, 26 having each a desired shape; the strip 11 is provided with embossing, and at the same time, the edge of strip 11 is provided with bending which compensates a stretch cased by the embossing. Further, loop control is performed between the stands of embossing roll and forming roll, and driving system of both rolls are synchronously controlled. In this way, the waves generating at the welding edge and the influence of material vibrations caused by the embossing are eliminated, and the speed-up of the production of titled blank pipe is achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a moon-shaped metal tube with an embossed pattern.

By embossing the sides of the square metal Z=V, the crushing load strength per unit area against vertical loads in the same direction as the two embossed surfaces is approximately three times that of a normal square metal steel pipe of the same size. It has been experimentally confirmed that it exhibits @-type strength.

Hereinafter, in the present invention, embossing refers to carving grooves at intervals on both side surfaces of the formed moon-shaped metal tube that are in instant contact with the contact surface. FIG. 1 shows a moon-shaped metal tube 31 having an embossed pattern 30.

Applications that take advantage of the above characteristics include, for example, use in skid materials for steel, and the ability to provide surface strength decoration with high loading capacity. Furthermore, by applying embossed patterns of the gods, it is possible to use it as a decorative member, etc., and the applications that take advantage of this customization are wide-ranging.

Methods for embossing square metal steel pipes include forming the square pipe into a square pipe and then using a core etc. on the tube circle to emboss it with a press, or embossing it in the form of a plate and pressing it. According to this method, the work process can be roughly divided into two.
Since it is a process, it cannot be said to be economical or efficient.

When manufacturing a rectangular metal tube by embossing with roll forming, continuously shaping the material with roll forming, and butt welding the ends of the coil edges, the following problems can be raised: First, when a steel strip is embossed, waves are generated at each emboss pitch at the weld edge.

Due to the generation of these waves, the left and right edges of the steel strip become wrapped, and welding becomes impossible, except when the left and right edges are welded together.

The generation mechanism of this wave can be considered as follows. When the emboss is formed, material is pulled from the flat plate around the emboss, elongating the material, and this spreads to the edge, producing periodic waves.

When rolling an embossed pattern, if the roll forming line of the rectangular metal tube is carried out on the same line, there is a problem that the influence of material vibration caused by the embossing will affect the roll forming of the previous round metal tube.

In view of this current situation, as a skit material for steel, square steel pipes with embossing on both sides of the square metal steel pipe are continuously embossed by roll forming, and then formed to a specified length. In a series of cutting steps, we conducted experiments on the manufacturing method and established a manufacturing method that satisfies the performance as a skit material.

That is, the gist of the present invention is to provide a method in which an embossed pattern is roll-formed on a steel strip, and a square shape having a welded seam on one side is obtained by roll forming, in which the edge portion of the steel strip is subjected to tension due to the embossing during embossing. The objective is to provide a roll load M to counteract this in parallel, perform loop control between the embossing roll stand and forming roll stand, and synchronously control the drive system of the embossing roll and the drive system of the forming roll.

The present invention will be explained below with reference to the drawings.

FIG. 2 is a detailed explanatory diagram of the present invention. In the figure, ankoi 7 10% strip material 11, embossing roll 14,
A pinch roll 13, a rough forming roll 15, a fin welding roll 16, a high frequency welding device 17, a squeeze roll 18, a cooling zone 19, a sizing roll 20, a Turk's rad roll 21, and a shearing device 22 are shown. In the present invention, the embossing roll 14 is provided with a DC control drive system 30, and the loop detector 23 is connected to the embossing roll 14 and the pinch roll 1.
A speed detector 24 is provided on the looper between the rough forming rolls 150 and on the inlet side of the rough forming roll 150.

The strip material to be used may be a strip, a slit coil, or a plate, and a strip or a slit coil is preferred in order to fully utilize the advantages of the continuous processing of roll forming. A coiled material such as a predetermined strip according to the size of the rectangular metal to be manufactured is introduced into an embossing roll through an uncoiler. The embossed pattern is formed on both sides of the rectangular metal tube, but in order to make the performance characteristics of this product effective, that is, to increase the crushing load strength, the embossed length should be made longer.
Therefore, it is best to extend the embossing length to both the left and right sides, near the top and bottom corners.

As mentioned earlier, in the conventional method, embossing creates waves at the welding edges, making it impossible to weld both ends of the steel strip, but in the present invention, in order to eliminate this problem, embossing is applied. At the same time as processing, a pair of upper and lower rolls with a constant radius of curvature (R+) on the upper side are added to the embossing roll, and the embossing roll is pressed down over the entire width of the material. The part is bent,
Kills the attraction of material from the periphery to form the emboss,
It is characterized by suppressing the spread of material elongation to the edges. Furthermore, by adding a flanged flange roll, meandering of the material can be prevented.

FIG. 3 shows an example of an embossing roll in the present invention.

In the figure, the embossing roll 14 is composed of an upper roll 14-1 and a lower roll 14-2.
5. A male mold 26 is provided on the lower roll in the desired shape described above. In the present invention, when the steel strip is formed into a rectangular metal pipe, the edge portion of the steel strip that becomes the upper side is bent by upper and lower rolls having a radius of curvature R8. Form. 29 indicates a flanged roll.

In general, a blank holder is used as a wrinkle suppressor during deep drawing of M plates.According to the knowledge of the present inventor, by simultaneously embossing the steel strip and bending the edge portion, it is possible to Even if green fluid was produced due to tension during processing, the wrinkle stress was canceled out by the combined use of the bending process using rolls, and it became clear at the time of the joint process that the bevel had no long-term defects. .

According to the invention, in addition to the above-mentioned bending process during embossing, rolling pressure is applied to the edge part of the area using a roll.
This can cancel out the tension caused by embossing and eliminate the above-mentioned problem of green liquor formation. Therefore, it is necessary to perform embossing and rolling down the edge portion at the same time.

The embossed steel strip 1] is introduced into the rough forming roll 15A via the pinch rolls 13, but in the present invention, the drive system for embossing roll processing and the drive system for roll forming are separated. This system solves the problem of the influence of embossing affecting the forming roll.

That is, according to the present invention, the drive system of the embossing roll and the drive system of the forming roll are separated, and the rotational speed of the embossing roll is increased by Will .In general, loop control is performed between the embossing roll stand and the forming rolls after the vinyl roll, and the drive system of the embossing roll and the drive system of the forming roll are made the same.With this method, embossing and roll forming can be separated. Since the forming process is carried out after the embossing process has been carried out, the forming process can be carried out stably without being affected by material vibrations caused by the embossing process.

Once the embossment is formed, the next step is to send it to a side bending roll. Note that the rolls for the next and subsequent steps are assembled in such a way as to avoid the sides on which the embossing is formed. As shown in Figure 2, the upper corner bending roll 15-A consists of an upper roll 15-4 and a lower roll 15-2, and the edge of the upper roll is formed by a caliber 27-2 having a radius of curvature R2. The material is given the desired curvature by facing the concave caliber on the edge of the lower roll, and at the same time, the material is bent at 60° ± 10° at the positions that should be the left and right upper corners when it is made into a square tube. It has a profile that bends up to . The radius of curvature R2 is set smaller than the half of the curvature on the row side during embossing<41R+,
It is desirable that the length be about (1 to 3) times the side length.

When the joint is welded, the firefly material is bent at a point 28 leaving widths Ll and L2 at both ends so that it has the length of the upper side of the rectangular tube. The bending position 28 is preferably a symmetrical position with respect to the roll center C. Next, the material is introduced into the '+AFM and shaping roll 15-B, and is bent by the upper roll and lower roll to a corner bending angle β of approximately 700±10°.
It is roughly formed into a cross-sectional shape with a triangular apex open.

The material whose upper and lower corners have been bent to an intermediate angle is sent to a fin pass roll 16 shown in FIG.

In fin pass machining, we actively utilized the reduction caused by fin pass rolls and introduced it into the welding process.

However, since both the left and right sides of the material are embossed and have rigidity, the rolls are not completely filled. In other words, by adding reduction, it is difficult to form a roll that contacts the embossed surface into a concave caliber so that the embossed surface protrudes in a convex shape, and to achieve sufficient filling. Even if it is formed into an overhanging shape, this is not desirable because the initially formed embossed shape will collapse.

In view of the above, in particular, the roll in contact with the embossed surface was made flat with no curvature. In addition, particularly in the present invention, for the purpose of stably butting in the welding process, the bending of the upper side is started from the concave curvature radius of the upper side at the welding roll, and the bending curvature at the fin pass is gradually decreased. It was introduced to welding rolls. In particular, setting the rate of change in the upper corner bending radius from the final roll of the fin pass to the welding roll is an important factor for stably butting and welding.

After preforming each side of the square tube material in this manner, it is subsequently introduced into a bath wetting roll having a predetermined roll profile, and subjected to electric resistance welding to form a tube.

As shown in FIG. 7, the welding rolls of the present invention are five-sided soybean rolls, and the function of each roll is such that two sets of upper rolls butt to form a butt shape. By adding a slight curvature (R) to the roll, stabilization of the butt can be achieved. Also, 1
The paired left and right rolls apply the necessary pressing force to the upset. Furthermore, it consists of a lower roll that acts like a safety valve to prevent the pipe material from escaping downward when pressure is applied by a pair of left and right rolls, and these valley rolls Highly reliable welding quality can be obtained.

The square tube material produced in this way is shaped into the final cross-sectional shape using several stages of shaping rolls, and then cut into a desired length using a suitable conventional shearing machine to produce a product.

As described above, according to the present invention, rectangular metal tubes can be produced at high speed by roll forming followed by embossing by roll forming, and the engineering effect is significant.

[Brief Description of the Drawings] Figure 1 is a schematic diagram of a rectangular metal tube according to the present invention, Figure 2 is an overall explanatory diagram of the present invention, Figure 3 is a partial sectional view of the embossing roll of the present invention, and Figure 4 is a schematic diagram of a rectangular metal tube according to the present invention. A partial sectional view of a rough forming roll of the present invention, FIG. 5 is a partial sectional view of another rough forming roll of the present invention,
FIG. 6 is a partial sectional view of the fin pass roll of the present invention, and FIG.
The figure is a partial sectional view of the squeeze roll of the present invention. 14: Embossing roll 15: +yfl forming roll 23
: Loop detector 24: Speed detector 30: DC control drive system

Claims (1)

[Claims] In the method of obtaining a rectangular blank pipe having a welded seam on one side by forming the embossed pattern on the steel strip with a roll 5y and roll forming, during embossing, the edge part of the steel strip is 1-roll canceled to cancel the tension caused by the embossing. The embossing pattern is characterized in that the embossing roll is applied in parallel, loop control is performed between the embossing roll stand and the forming roll stand, and the drive system of the embossing roll and the destination of the forming roll are synchronously controlled. A method for forming a moon-shaped metal tube.