JPH02220716A - Manufacturing equipment for seam welded pipe - Google Patents

Abstract

PURPOSE:To prevent generation of a line trouble caused by a welding excess metal part by cutting and eliminating a horizontal seam welding bead excess metal part in an entry process, and providing a means for drawing back one roll in a forming process. CONSTITUTION:By providing a bead remover 3 on an entry process for bringing each end part of a strip coil C to horizontal seam welding and feeding to the next process, a horizontal seam welding bead excess metal part B is cut and eliminated. In the subsequent forming process F, a roll quick open device 12 is provided on the lower roll Rl of a breakdown mill 5, and by bringing the roll to drawback instantaneously before an excess metal part B' which remains in the center part of a plate material P passes through, damage of the mill 5 is prevented. By returning the roll instantaneously after the excess metal part B' passes through, a resistance welded tube is manufactured stably.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention involves cross-splicing strip coils one after another, continuously feeding the strips into a mill line to form a tube, and then welding the seam portions. The present invention relates to an electric resistance welded tube manufacturing facility for obtaining electric resistance welded tubes.

[Prior art and problems to be solved by the present invention] As shown in Fig. 1, the electric resistance welded pipe manufacturing equipment consists of an entry process E, a forming process F, a seam welding process W, etc. In step 1, the strip coil C is unwound and connected to the end of the preceding coil by flash butt welding, and the endless plate material is sent to the next process. Gradually bend and form into a tube shape, squeeze roll
The seam is welded using a welding machine 8, and the cooling zone 9
The welded part is cooled, the outer diameter is reduced in a sizing zone 10, and the cutoff machine 11 cuts it to a predetermined length.

In such a line configuration, there are weld bead excess parts on both upper and lower surfaces of the horizontal joint part of the coil, and if this is passed through the mill line without maintenance, the following problem will occur.

(i) The Nα2 to Nα4 stands of the breakdown mill 5 are overloaded, causing damage to the mill. That is, since the plate material is sandwiched between the upper and lower rolls, the excess portion causes the same situation as sudden changes in the plate thickness, leading to accidents such as breakage of the roll shaft of the breakdown mill and damage to the rolling device.

(ii) The contact tip of the welding machine, the inner bead removal tool, and the outer surface bead removal tool are damaged by the excess portion.

Therefore, conventionally, the horizontal joint welded portion is cut and removed over the entire width of the plate by using a cylindrical cutter from above and below. However, as the width of the plate becomes wider (the diameter of the tube is larger), the excess portion cannot be removed completely, so it must be corrected manually using a grinder.

However, such a method requires manpower and has the problem that it takes time to correct both the upper and lower surfaces, which reduces the operating rate of the equipment.

Furthermore, if it cannot be completely corrected, the above-mentioned problems will occur.

This invention was made to solve these problems, and its purpose is to provide electric resistance welded pipe manufacturing equipment that can reliably prevent line troubles due to cross-welded excess parts without requiring manual correction. It is about providing.

[! ! Means to solve the problem]

As shown in FIG. 1, the electric resistance welded pipe manufacturing equipment according to the present invention includes an entry process E in which the ends of a strip coil C and a strip coil C are cross-joined and supplied to the next process, and a plate material is gradually bent. In the equipment having a forming process F in which the seams are formed into a tubular shape, and a seam welding process W in which the seam parts are welded, after the entry process, a cross-joint weld bead excess part B on the upper and lower surfaces at both ends in the width direction of the plate material after the cross-joint is applied. A bead remover 3 capable of cutting and removing the material is provided, and the breakdown mill 5 in the forming step F is provided with a quick oven device 12 capable of releasing at least one roll in a direction away from the plate material.

As shown in FIG. 2, the bead remover 3 only needs to be able to completely remove about 50 to 100 mm of the extra portions B' at both ends of the plate material P from both the upper and lower surfaces, for example, by rotating a pair of upper and lower cylindrical cutters 3A. Then, only the upper and lower excess portions B' are removed.

This cutting tool is not limited to the horizontal rotating shaft type cutter 3A shown in FIG. 2, but may also be a vertical rotating shaft type face milling cutter, a cutting tool of a predetermined width, or the like.

The quick oven device 12 includes a pair of upper and lower rolls Ru,
installed on both or one of the rolls R1 and
A drive device that can instantly move up and down. In addition, in the breakdown mill 5, the upper roll Ru is of an electric lift/lower type, and as described later, in order to avoid the remaining upper and lower excess portions B', the lower roll R1 is missed and the plate material P is It is easier to avoid by lowering it by its own weight, so lower roll Rf
It is preferable to raise and lower only the Furthermore, the lower roll R1
is a drive roll, which is preferably a double-acting ram type hydraulic cylinder in order to instantly return the lowered roll as will be described later (see FIG. 4).

[For production]

When the horizontal seam welding is completed, the bead remover 3 pinches both ends of the plate material P, and while moving the plate material P, remove the excess portion B'.
Cut and remove. This cutting and removal is not performed over the entire width of the board, but at most 50 to 100 m at the end, so that both the top and bottom surfaces can be completely removed, so it can be done automatically without the need for manual correction.

As shown in FIG. 3, the oven seam tube formed in the forming process F has the excess portions on both sides of the seam removed, so it is difficult to connect to the contact tip T of the welding machine 8 and to the subsequent stage This prevents damage to the inner and outer bead removal bits Bi.

In the breakdown mill 5, the excess portion B' remains on the upper and lower surfaces in the center of the plate material P, so the rolls are instantly retracted before this excess portion B' passes to prevent damage to the mill. . After the excess portion B' has passed, it is instantly returned to its original position so that stable pipe manufacturing can be performed.

Mills other than breakdown mills are structured in such a way that when processing each coil intermittently, the shock when the front and rear ends of the plate material pass is approximately twice the normal operating load. The load due to the excess portion B' increases by only about 20%, and in fact, the load is reduced.

In addition, when there are four breakdown mills 5, the KL mill uses a common roll for all tube manufacturing sizes, and is set with a margin for the plate thickness, so the excess portion B' Even if they pass through, there is hardly any overload. Therefore, in this case, quick open devices 12 are provided for three units, N112 to Na4.

The operation timing of each breakdown mill 5 is determined by detecting the excess portion B' on the entrance table of the forming process F, counting the amount of movement of the plate material, and tracking, and sequentially quick-opening from Nf12 to Nf14. To go.

However, the quick opening should be done one by one, and the others should be kept closed so that the plate material P can be stably made into pipes.

〔Example〕

This is done by modifying the existing entry equipment that intermittently supplies strip coils one by one, and
In this case, the material is intermittently conveyed directly to the forming process F via the bypass table 13, and in the case of a thin plate, it can be continuously supplied as an endless plate material by the looper 14 and the shear welder 2. (See Figure 5).

In the case of a thin plate, the rear end of the preceding coil in the looper 14 and the tip of the trailing coil C unwound by the uncoiler 15 are cut by the shear welder 2, and then butted and welded, and the plate material in the looper 14 is fed out. This enables cross-seam welding to be performed without stopping the subsequent process.

A bead remover 3 is provided between the shear welder 2 and the entry side tilt table 16 of such entry equipment 1, and a roll quick open device 12 is provided in the breakdown mill 5.

As shown in FIG. 6, the bead remover 3 includes a pair of upper and lower cylindrical cutters 3A, which are rotatably driven by a hydraulic motor 17, arranged in a stand 1B so as to be vertically movable, and a pair of cylindrical cutters 3A that are rotatably driven by a hydraulic motor 17. The cutters 3A are configured to move up and down synchronously in the direction of approaching or separating from each other.

As a result, the pair of cylindrical cutters 3A normally stand by in an open state, and close when removing the excess portion to cut and remove the excess portion at both ends of the plate material. Further, the stands 18 disposed on both sides of the center of the pass line are movable in the width direction of the plate material, and their positions can be adjusted according to the size of the plate material.

The roll quick oven device 12 is a double-acting ram-type hydraulic cylinder, and has a lower roll RI of 2 mils shown in FIG. 4 and 3.4 mils shown in FIG. .

Provided for. The lower roll R2 has a roll chock 20 that is vertically slidable within a stand 21, and a hydraulic cylinder 12 is disposed below the roll chock 20.

A control valve (not shown) is connected to this hydraulic cylinder 12, and the controller uses signals from an excess portion detector and a sheet material movement amount detector to perform traction and shaking on the excess portion, and lowers the excess portion just before it passes. Roll R1 is lowered, and after passing, the lower roll Rf is instantaneously lowered.
It is designed to increase fi.

[Effects of the Invention] As described above, the electric resistance welded pipe manufacturing equipment according to the present invention uses a bead remover to remove only the excess portion of the cross-joint weld bead from both ends of the plate material after the cross-joint, thereby reducing the breakdown of the forming process. In the mill, the roll is released by a quick-open device and passed through the remaining excess, so there is no need to manually correct the cut and removed part, and it also prevents damage to the contact tip of the welding machine and prevents damage in the breakdown mill. Damage can be prevented.

This makes it possible to improve the operating rate of the equipment.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the line configuration of the electric resistance welded pipe manufacturing equipment according to the present invention, FIG. 2 is a schematic diagram showing the beam remover,
Fig. 3 is a sectional view showing the seam welding state, Fig. 4 is a schematic view showing the breakdown mill, Fig. 5 is a side view showing an example of entry equipment, Fig. 6 is a front view showing the beam remover, Fig. 7 The figure is a front view showing an example of a breakdown mill. 1... Entry equipment, 2... Scher welder 3... Bead remover, 4...
Looper 5... Breakdown mill 6... Cluster side roll 7...
Finbath mill 8...Squeeze roll/welding machine 9...
Cooling zone 10... Sizing zone 11... Cut-off machine 12... Quick open device 13...
・Bypass table 14... Looper 15... Uncoiler 16... Inlet tilt table 17... Hydraulic motor, 18... Stand 19.・・・・Lifting/lowering/synchronization mechanism

Claims (1)

[Claims] (1) An entry process in which the ends of the strip coil and the strip coil are cross-joined and fed to the next process, a forming process in which the plate material is gradually bent and formed into a tubular shape, and a seam welding process in which the seam portions are welded. In the electric resistance welded pipe manufacturing equipment, a bead remover capable of cutting and removing the cross-joint weld bead excess on the upper and lower surfaces at both ends in the width direction of the plate material after the cross-joint is installed in the entry process, and a breakdown mill in the forming process is equipped with a ERW pipe manufacturing equipment characterized by being provided with a quick open device capable of releasing at least one roll in a direction away from a plate material.