JP5515423B2 - Large coil manufacturing equipment for ERW steel pipes - Google Patents

Description

  The present invention relates to the manufacture of large coils for electric resistance welded steel pipes, and in particular, large coils used as pipe forming materials for medium and large diameter electric resistance welded steel pipes (outer diameters 318.5 to 660.4 mm). The present invention relates to an apparatus for manufacturing a rolled steel strip.

In Patent Document 1, in a method of manufacturing a seam tube while sequentially connecting coils, a surplus length (1) of a pipe good product after cutting out a standard pipe at the end of pipe production of a preceding coil during the production of the seam pipe. ₀ ) is predicted, and the length of the unformed portion of the preceding coil is controlled by a rolling mill provided in the former stage of the forming mill so that the extra length (l ₀ ) becomes zero.
Patent Document 2 discloses a steel strip unwinding device and a winding device at both ends, and an inspection device and a steel strip for inspecting the steel strip from the upstream side between the unwinding device and the winding device. An apparatus for manufacturing a steel strip having a cutting device for cutting a steel strip, comprising a joining device for joining the ends of the preceding steel strip and the succeeding steel strip on the entry side of the winding device. Have been described.

JP-A-55-130332 JP 2003-290826 A

In the manufacture of ERW steel pipes, there is always a loss at the front and rear ends of the coil, and due to the characteristics of ERW steel pipe mill, the minimum coil length that can be piped is determined, which is shorter than that. There is a problem that a coil (short coil) cannot be used for pipe making.
Patent Document 1 describes a method for joining the leading and trailing coils online in order to solve the above-mentioned two problems. However, a large-diameter ERW pipe mill such as a 26 "ERW mill is disclosed. In order to use the same means, the equipment such as a looper becomes enormous. Moreover, since the 26 "ERW mill produces a thick material up to a plate thickness of 1" (25.4 mm), it is necessary to drive it. A large amount of power is required, and not only the construction cost but also the running cost is huge.

  Patent Document 2 describes a method of inspecting, cutting, and joining coils off-line in order to increase the efficiency of users and manufacturers and to order and deliver steel strips with good yield. Effective measures are not taken against the end-of-coil end mark, which is a problem with coils, and the instability of molding at the coil seam cannot be eliminated. The effect of reduction is limited.

  As described above, when trying to improve the pipe making yield of large coils for ERW steel pipes, the conventional on-line coil joining means increases the equipment cost or running cost, or the conventional off-line coil joining means has a yield improvement effect. However, these points were left as unsolved issues.

In order to solve the above-mentioned problems, the inventor has devised a means of sequentially joining a plurality of coils offline, correcting the end mark by a leveler, and then transporting the ground to the pipe forming line entrance side.
That is, the present invention is as follows.
(1) An uncoiler that sequentially develops a plurality of hot-rolled coils that are used as constituent parts of a large-sized coil to be used as a pipe-forming material on the inlet side of a pipe-making line that manufactures an ERW steel pipe having an outer diameter of 318.5 to 660.4 mm . Coil joining means for joining the developed steel strip and the subsequent steel strip, the leveler for straightening the joined steel strip, and the coiler for winding the straightened steel strip, a turntable for reversing the front and rear of the wound formed by the coil, said to have a coil conveyor for conveying the front and rear reversed coil to the inlet side of the pipe production line, the coil joint means, said preceding steel strip and the trailing A shear that cuts off the extra length portion from the opposite end to the steel strip, a plate joint welding machine that welds the opposite end after the cutting, and a bead cutting machine that cuts the bead generated by the welding. Large-size core for ERW steel pipe Le of manufacturing equipment.

  According to the present invention, in the manufacture of medium and large diameter electric resistance welded steel pipes, it is possible to reduce the leading and trailing end losses while keeping the load of equipment cost or running cost much smaller than the on-line coil joining means, and the short coil inventory. The amount of waste and the amount of scrap can be greatly reduced, and a great effect of improving the pipe making yield is achieved.

Schematic layout diagram showing an example of an embodiment of the present invention The schematic side view which shows the suitable form of this invention apparatus

  The present invention is applied to a pipe making line as shown in FIG. This pipe making line includes an uncoiler 11 that linearly develops a large coil (coil used as a material of a medium / large diameter electric resistance welded pipe) in order from the entry side to the exit side, and the steel strip S that is developed. A molding machine 12 for forming an open pipe P1 having an open seam part; an electric seam welding machine 13 for joining the open seam part by electro-welding to form a seam part; and making the open pipe a seam pipe P2. It has a seam annealer 14 that heat-treats the seam portion, a sizer 15 that adjusts the outer diameter of the seam tube, and a traveling cutting machine 16 that cuts the seam tube P2 that is running after adjusting the outer diameter to a predetermined length.

Conventionally, as the large coil, a single (unbonded) hot rolled coil is conveyed from the coil yard 10 to the inlet side of the pipe making line.
On the other hand, in this invention, this invention apparatus is installed in the installation place coordinated to the area | region containing the coil conveyance path from a coil yard to a pipe making line entrance side.
As shown in FIGS. 1 and 2, the present invention apparatus comprises an uncoiler 1 that sequentially expands a plurality of hot-rolled coils C1 that are constituent parts of the large coil, and a preceding steel strip S1 that is expanded. Coil joining means 2 for joining the trailing steel strip S2, a leveler 3 for straightening the joined steel strip S, a coiler 4 for winding the straightened steel strip S, and the winding And a coil conveyor 7 that conveys the coil C2 reversed in the front-rear direction to the inlet side of the pipe making line.

The coil joining means 2 includes a shear 2A for cutting off the extra length portion from the opposed end portions of the preceding steel strip S1 and the succeeding steel strip S2, and a plate welding machine 2B for welding the opposed end portions after the cutting. It is preferable to include a bead cutting machine 2C that cuts the bead portion generated by the welding from the viewpoint of preventing poor bonding and preventing the occurrence of the pressing claw on the coil C2 by the bead portion protrusion.
Both the uncoiler 1 and the coiler 4 preferably have a mandrel 20 and a coil opener 21 so that roles can be exchanged with each other.

  The present invention was applied to a 26 "ERW mill in the embodiment illustrated in FIGS. 1 and 2. The processing capacity after application was 170 t / hr. Compared to the conventional case where a hot-rolled coil was used alone, The leading and trailing end losses can be reduced by 4 m per hot-rolled coil, and the short coil inventory and scrapping amount can be greatly reduced, resulting in a significant improvement in tube-making yield.

DESCRIPTION OF SYMBOLS 1 Uncoiler 2 Coil joining means 2A Shear 2B Joint welding machine 2C Bead cutting machine 3 Leveler 4 Coiler 5 Turntable 7 Coil conveyor 10 Coil yard 11 Uncoiler (belonging to pipe making line)
12 Forming Machine 13 Electric Welding Machine 14 Seam Annealer 15 Sizer 16 Traveling Cutting Machine 20 Mandrel 21 Coil Opener C1 Hot Rolled Coil C2 Coil S after Joining Steel Strip (Succeeding numeral 1 means preceding, 2 means following)
P1 open pipe P2 seam pipe

Claims (1)

An uncoiler that develops a plurality of hot-rolled coils in a straight line sequentially into a large coil serving as a material for pipe making to the inlet side of a pipe making line that manufactures ERW steel pipes with outer diameters of 318.5 to 660.4 mm, Coil joining means for joining the preceding steel strip and the following steel strip, a leveler for straightening the joined steel strip, a coiler for winding the straightened steel strip, and the winding a turntable for reversing the front and rear coil comprising Te, the front and rear inverted coil have a coil conveyor for conveying to the inlet side of the pipe production line, said coil connecting means includes a said preceding steel strip and the succeeding steel strip Comprising: a shear that cuts off the extra length from the opposite end of the plate, a plate joint welder that welds the opposite end after the cut, and a bead cutting machine that cuts the bead generated by the welding. Of large coil for ERW steel pipe Forming apparatus.

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