JPH04178221A - Device for forming resistance welded steel tube - Google Patents

Abstract

PURPOSE:To feasibly use for either thin wall material or thick wall material by arranging the forming stand of the specific structure before the fin pass stands group of the line of the resistance welded steel tube forming. CONSTITUTION:On a forming stand to be assembled, a top roll 16 is set to the upper side of a driving bottom roll 15 so as to be adjustable to the upward and downward direction. An inside roll 21 moves together with the top roll 16, and can be positioned upward and downward corresponding to the tube diameter. Therefore, the enough driving force can be obtained by combinating the driving bottom roll 15 and the top roll 16. And the variation of the height direction of the material is prevented with the top roll 16. The fluting of the thin wall material is prevented by combinating the inside roll 21 and the outside roll 26. And the edge stretching can be prevented by arranging plural stages of the outside roll 26 to the longitudinal direction.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an apparatus for forming an electric resistance welded steel pipe.

[Prior Art] A forming line for electric resistance welded steel pipes has a construction as shown in FIG. 3 inside the membrane.

The raw material coil 1 is made into a predetermined width by a slitter 2,
Intermediate forming is performed by a breakdown stand group 3 and cluster stand group 4, final forming is performed by a fin pass stand group 5, and welding is performed by a welding machine 6 and a welding machine roll 7.

Conventional forming mills include: 1) a cage roll system in which a plurality of cage rolls 8 are arranged in the circumferential direction instead of a cluster stand group; 2) a cluster stand group is replaced with a horizontal roll 9, a top roll 10 and A step roll system (FIG. 5) consisting of side rolls 11 is adopted.

[Problems to be Solved] By the way, the cage roll method has the following advantages for thin-walled materials: continuous forming allows for smooth loading into the fin pass stand, and prevents elongation due to edge buckling. Although it is suitable for forming thin-walled materials, there is a problem in that it lacks driving force and forming force for thick-walled materials.

On the other hand, the step roll method is suitable for forming thick-walled materials because sufficient driving force and forming force can be obtained by driving the rolls, but there is a problem in that edge elongation occurs with thin-walled materials. .

An object of the present invention is to provide an apparatus for forming electric resistance welded steel pipes that can be applied to both thin-walled materials and thick-walled materials without any problems.

[Means for Solving the Problems] The ERW steel pipe forming apparatus of the present invention includes a drive bottom roll and a top that is provided in front of a fin pass stand group of an ERW steel pipe forming line and whose position is adjustable in the vertical direction. A roll, an inside roll whose position can be adjusted on both sides of the top roll, and an outside roll which acts near the coil edge and can be adjusted by 1 fm in the vertical and horizontal directions. It is characterized by the arrangement of a molding stand consisting of:

[Function] Sufficient driving force can be obtained by the combination of the driving bottom roll and top roll. Additionally, the top roll prevents the material from fluctuating in the height direction.

The combination of the inside roll and the outside roll can prevent the thin material from buckling. Moreover, edge elongation can be prevented by arranging multiple stages of outside rolls in the longitudinal direction.

In this way, the shape of the open pipe in front of the fin pass stand can be made close to the fin bus roll caliber, ranging from thin-walled materials to thick-walled materials.

[Example] First, the U-line fishing configuration of the forming stand incorporated into the apparatus of the present invention will be explained with reference to FIG.

A top roll 16 is provided above the drive bottom roll 15 so that its position can be adjusted in the vertical direction.

The inside roll 21 moves up and down together with the top roll 16, and can be positioned in accordance with the pipe diameter.

The outside roll 26 can be positioned in the horizontal and vertical directions in accordance with the pipe diameter.

Thus, the driving bottom roll 15 and top roll 16°
Sufficient driving force can be obtained in combination with Further, the top roll 16 prevents the material from fluctuating in the height direction. The combination of the inside roll 21 and the outside roll 26 can prevent the thin material from buckling. Also, outside roll 26
By arranging multiple layers in the longitudinal direction, edge elongation can be prevented.

In this way, the shape of the oven vibe in front of the fin-pass stand can be made close to the fin-bath roll caliber for both thin and thick materials.

Next, the specific configuration will be explained with reference to FIG. 2.

The bottom roll 15 is rotatably driven via four shafts 15g driven by motors (not shown). Further, the height of the driving bottom roll 15 can be adjusted by using a liner.

The top roll 16 is assembled into a retaining bracket 17. This holding bracket 17 is replaceably attached to a frame 18 that is driven up and down by an electric motor. In this way, the top roll 16 and the holding bracket 17 can be replaced depending on the pipe size.

The inside roll 21 is rotatably held by a holding part 22, and this holding part 22 is attached to a holding bracket 17. In this way, the aside roll 21 is moved up and down together with the top roll 16. Further, the inside roll 21 and the holding part 22 can be replaced depending on the pipe size. On the other hand, a shim (not shown) is provided between the holding bracket 17 and the holding part 22.
By interposing the inside roll 21, the position of the inside roll 21 is determined.

The outside roll 26 is attached to the holding part 27 via a bearing. And outside roll 26
The holding portion 27 can be adjusted in position in the horizontal and vertical directions using a screw shaft.

[Effects of the Invention] The electric resistance welded steel pipe forming apparatus of the present invention is as described above, and can bring the shape of the oven vibe before the fin pass stand close to the fin pass roll caliber for both thin and thick materials.

In this way, it is possible to stably mold a large-diameter, thin-walled, high-tensile-strength material of the APIX40 class with a t/D of about 1%, for example, while preventing edge pack ring. Moreover, by making the wall thickness distribution near the welded part uniform, quality can be improved.

Furthermore, fin pass reduction can be reduced and mill load can be reduced.

Furthermore, by reducing loss at the front and rear ends of the coil, yield can be improved.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the basic configuration of a forming stand incorporated in the device of the present invention, Fig. 2 is an explanatory diagram showing an embodiment of the forming stand incorporated in the device of the present invention, and Fig. 3 is an explanatory diagram showing an embodiment of the forming stand incorporated in the device of the present invention. The line explanatory drawings, FIGS. 4 and 5, are explanatory drawings showing the configuration of a conventional forming mill, respectively. 4...Cluster stand group 5...Fin pass stand group 15...Bottom roll 16...Top roll 21...Inside roll 26...Outside roll Patent attorney Patent attorney Takehiko Suzue Procedure amendment Book Heisei 3.i.17EI

Claims (1)

[Claims] In front of the fin pass stand group of the ERW steel pipe forming line, there is a driving bottom roll, a top roll whose position is adjustable in the vertical direction, and an inside roll which is installed on both sides of the top roll so that its position can be adjusted. It is characterized by the arrangement of an outside roll that acts near the coil edge portion and whose position can be adjusted in the vertical and horizontal directions, and a molding stand consisting of a plurality of steps provided in the longitudinal direction. Forming equipment for ERW steel pipes.