JPH0663748A - Continuous automatic butt welding equipment for round steel - Google Patents

Abstract

PURPOSE:To enable a continuous automatic welding with unmanned operation for butt welding of round steel by controlling a welding torch height adjusting mechanism and round steel rotating device by means of a welding torch height each the rotation and rotating speed of round steel, which are computed by arithmetic part. CONSTITUTION:A rotating speed of round steels 1, 1 is controlled so as to make the welding speed in response to welding bead height varying at each cladding constant, further, controlling the welding torch height so as to make the distance between a welding surface 2 and welding torch 15 in response to the welding bead height varying at each cladding. Also, slag generated at the welding surface 2 at each cladding is automatically removed by an automatic slag removing machine 21 with following the changes of ruggedness of the welding surface 2 and welding diameter, butt welding of the round steels 1, 1 is able to be done with continuous automatic welding. Accordingly, automation under the constant welding condition becomes possible, further, contributing to the improvement of welding part's quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic continuous butt welding apparatus for round steel bars used for manufacturing mandrel bars used in the process of manufacturing seamless steel pipes.

[0002]

2. Description of the Related Art A mandrel bar used in the process of manufacturing a seamless steel pipe, for example, a seamless steel pipe by the Mannesmann mandrel mill system, has a long length of 20 to 30 m or more. Therefore, the long mandrel bar is
It is manufactured by butt-welding a raw steel bar (tool steel) by manual welding of covered arc welding. This butt welding work for steel bars is a continuous work for a long time in a bad environment, which must be carried out in multiple layers in order from the small diameter of the butt portion of round steel, and is avoided by welders. .

In manual welding of the above-mentioned covered arc welding,
Since a welding rod with a length of 300 to 500 mm is used,
Since the arc is interrupted at a pitch of 200 to 500 mm, defects such as poor fusion and poor fusion at the bead joint are likely to occur, and slag generated on the surface of the weld must be usually removed manually, which is extremely It is efficient. On the other hand, if a semi-automatic welding method using gas shielded arc welding is adopted, it is considered possible to continuously weld butt round steel while rotating.

[0004]

However, the semi-automatic welding method by gas shielded arc welding is a method of continuous welding while rotating butt round steel bars, and the welding speed increases as the round steel speed is kept constant. Becomes
Poor fusion defects are likely to occur. Further, it is necessary to remove the slag in every 1 to 3 layers, the arc must be stopped to remove the slag, and defects such as poor fusion and poor fusion are likely to occur at the bead joint portion. Further, there is a problem that it is necessary to lift the welding torch by the amount of the stacked layers for each stacked layer to keep the protruding length of the welding wire constant.

An object of the present invention is to provide a continuous round steel butt welding automatic welding device capable of performing continuous automatic welding between the first layer and the final layer in the butt welding of the round steel by unmanned operation.

[0006]

[Means for Solving the Problems] The inventors of the present invention have made extensive studies to achieve the above object. As a result, in butt welding of round steel with a gas shielded arc welder having an automatic welding wire feeding function, in order to keep the welding speed of the welding conditions constant, the rotation speed of the round steel should be changed for each diameter of the welded part. The welding torch may be sequentially raised in response to changes in the diameter of the weld to maintain the welding voltage and welding current constant, and the slag generated on the surface of the weld may be automatically removed during continuous welding. The present invention has been reached through the investigation.

That is, the present invention relates to a welding torch height adjusting mechanism added to a welding machine in a device for continuously automatically welding a butt portion while rotating a round steel by a welding machine having a welding wire automatic feeding function, and a round steel. Bead height detector located above the butt part of the, round steel rotation detector, rotation speed control function added to the round steel rotating device, automatic slag removal to press the chipping hammer into the welded part with a predetermined load Machine, the bead height input from the bead height detector, the signal for each rotation of the round steel input from the rotation detector, and the welding conditions set and input from the operation panel, based on the welding condition of the round steel. The calculation unit that calculates the welding torch height and rotation speed for each rotation, and the welding torch height adjustment mechanism and the round steel rotating device are used by the calculation unit to calculate the welding torch height and rotation speed for each rotation of the round steel. Welding control to control It consists of a device which is round steel butt continuous automatic welding device according to claim.

In the automatic slag remover of the present invention, a copying roller which comes into contact with an air cylinder and a copying ring inserted into a round steel is disposed on a slag removing machine stand having a copying shaft at the rear portion, A weight is connected via a wire to a chipping hammer that can be moved forward and backward on a slide base that is moved forward and backward by an air cylinder, and the chipping hammer is pressed against the welded portion with a predetermined load.

[0009]

According to the present invention, a butt continuous welding apparatus for round steel, a welding torch height adjusting mechanism, a bead height detector, a round steel rotation detector, a rotation speed control function, and an automatic slag removing device are provided. Machine, the bead height input from the bead height detector, the signal for each rotation of the round steel input from the rotation detector, and the welding conditions set and input from the operation panel, based on the welding condition of the round steel. The calculation unit that calculates the welding torch height and rotation speed for each rotation, and the welding torch height adjustment mechanism and the round steel rotating device are used by the calculation unit to calculate the welding torch height and rotation speed for each rotation of the round steel. Since the welding control device to control is installed,
To keep the welding speed constant based on the bead height input from the bead height detector, the signal for each rotation of the round steel input from the rotation detector, and the welding condition set and input from the operation panel. Since the rotation speed of the round steel is fast in the first layer weld portion having a small diameter and becomes slower as it approaches the final layer having a larger diameter, it is necessary to control the rotation speed of the rotating roll for each welding stack.

For example, in order to keep the welding speed V constant, the diameter of the rotating roller: DT, the outer diameter of the round steel: D, the diameter of the welded portion:
Assuming dn, the round steel rotation speed (rpm) = V / πdn, the rotation roller rotation speed (rpm) = V / πdn × D / DT,
Motor rotation speed (rpm) = rotation roller rotation speed / reduction ratio, the motor rotation speed is calculated according to the weld zone diameter that changes for each layer of the weld zone, and the rotation speed control function of the motor is controlled to control the rotation speed. Can be carried out. In addition, since the welding torch height adjustment mechanism is added to the butt continuous welding equipment for round steel, the welding bead height input from the bead height detector and the round steel input from the round steel rotation detector are Based on the signal for each rotation, the welding torch can be automatically raised by the raised welding bead height for each rotation of the round steel, and the welding voltage and welding current of the welding conditions can be kept constant.

Further, in order to remove the slag generated on the surface of the welded portion for removing the defect in the welded portion, the slag removing machine having the copying shaft at the rear portion is lifted with the copying shaft as a fulcrum,
The copying roller is brought into contact with the copying ring inserted into the round steel. Then, by advancing the slide base by the air cylinder to bring an air hammering type chipping hammer into contact with the welded portion, the tipping hammer is connected to the welded portion with a weight through a wire and press-contacted with a predetermined load,
The slag generated on the surface of the welded portion can be continuously and automatically removed by a chipping hammer by easily following changes in the diameter of the welded portion and unevenness of the welded surface.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to FIGS. FIG. 1 is an overall schematic view of a round steel butt continuous automatic welding device of the present invention, FIG. 2 is a schematic view of a rotating device for rotating round steel, and (a) is a front view.
(B) is a plan view, FIG. 3 is a welding torch automatic raising outline diagram, (a) diagram is a front view, (b) diagram is a side view, and FIG. 4 is an outline diagram of an automatic slag removing device, (a) The figure is a plan view, (b)
FIG. 5 is a front view, FIG. 5 shows a chisel tip shape of a chipping hammer, (a) is a front view of an example of the present invention, (b)
The figure is a front view of a conventional shape.

In FIG. 1, 1 is round steel for butt welding,
Reference numeral 2 indicates a welded surface of the butt portion of the round steel 1. Reference numeral 3 is a round steel rotating device for rotating the round steels 1 and 1 to be butt-welded in the circumferential direction along the outer diameter of the round steels. As shown in FIG. 2, the round steel rotating device 3 has a drive motor 4 for rotating the round steel 1 and a speed reducer 5 to smoothly rotate the round steel 1 in the circumferential direction along the outer diameter of the round steel 1 without uneven rotation. , The drive rotating roller 7 of the pair of rotating rollers is directly connected to the drive shaft 6 by two of the drive rotating roller 7 and the rotation free roller 8, and
Since the bending of the round steel 1 in the axial direction is predicted when the round steel 1 is long, the structure is such that the pinch roll 9 holds the round steel 1 from above, and the driving rotary roller 7 and the rotary free roller 8
A set of two rotating rollers is installed according to the length of the round steel 1. If the round steel 1 is short, the round steel 1
Can also be rotated by the chuck of the rotary positioner. Further, the rotation detector 1 is attached to the rotation shaft of the pinch roll 9.
0 is installed and is configured to detect one rotation of the round steel 1.

Reference numeral 11 denotes a gas shielded arc welding machine having a welding wire automatic feeding mechanism, a welding wire 13 to which a welding power source 12 is connected, a welding wire feeding motor 14 for automatically feeding the welding wire 13, and a welding torch. A welding torch height adjusting motor 16 for adjusting the height of 15 and a shield gas supply device (not shown), and a welding wire feeding motor so that the welding wire 13 is fed from the operation panel 19 to the welding controller 20. Fourteen speed controls are implemented. Further, the torch height adjusting motor 16 for adjusting the height of the welding torch 15 is used for the welding bead height detector 1
Based on the height of the welding surface 2 input to the arithmetic control unit 18 from 7 and the one rotation detection signal of the round steel 1 input from the rotation detector 10 to the arithmetic control unit 18, every one rotation of the round steel 1. The height of the welded bead is calculated on the operation panel 1
Welding control device 20 so that the welding speed is set from 9
The welding torch 15 is controlled to be automatically raised via the. Further, the arithmetic and control unit 18 determines the welding surface 2 based on the height of the welding surface 2 input from the welding bead height detector 17 and the one rotation detection signal of the round steel 1 input from the rotation detector 10. In order to set the welding speed V set from the operation panel 19 according to the welded portion diameter that changes for each stacking of the rotating roller diameter: DT, round steel outer diameter: D, welded portion diameter: dn,
Round steel rotation speed (rpm) = V / πdn, rotation roller rotation speed (rpm) = V / πdn × D / DT, motor rotation speed (rpm) = rotation roller rotation speed / reduction ratio The rotation speed of the drive motor 4 is controlled for each rotation of the round steel 1 in accordance with the diameter of the welded portion that changes for each stack.

On the other hand, as shown in FIG. 4, the automatic slag remover 21 has an air cylinder 24 and a copy ring 25 inserted into the round steel 1 and fitted on a slag remover stand 23 having a copy shaft 22 at the rear. A contact roller 26 is provided, and a weight 30 is connected via a wire 29 to a chipping hammer 28 provided so as to be able to move forward and backward on a slide base 27 that moves forward and backward by the air cylinder 24. When a slag removing command is output from the arithmetic and control unit 18, the automatic slag removing machine 21 moves the slag removing machine base 23 up along the shaft 22 as a fulcrum by an elevating means (not shown),
The copying roller 26 is brought into contact with the copying ring 25 inserted into the round steel 1. Then, the slide base 27 is moved forward by the air cylinder 24 to bring the tip of the chisel 31 of the air hammering type chipping hammer 28 into contact with the welding surface 2.
A chipping hammer 28 is connected to the welding surface 2 through a wire 29 and a weight 30 is connected to the welding surface 2 so as to press-contact with a predetermined load. The tip shape of the chisel 31 is changed to the conventional chisel 41 having a sharp tip as shown in FIG. 5 (b), and as shown in FIG. 5 (a), the chisel 31 can be easily adjusted to the unevenness of the welding surface 2 and the change of the welding diameter. Wide width in the vertical direction to allow tracking. Further, when the round steels 1 and 1 are displaced in the axial direction during welding, the copying roller 26 and the copying shaft 22 that come into contact with the copying ring 25 inserted into the round steel 1 cause the round steels 1 to move. Follow the positional deviation of 1.

Since the above construction is adopted, in the butt continuous automatic welding of the round steels 1 and 1, the rotation speed of the round steels 1 and 1 is a signal input from the rotation detector 10 for each rotation of the round steels 1. In order to keep the welding speed constant based on the welding bead height for each rotation of the round steel 1 input from the welding bead height detector 17 and the welding condition input from the operation panel 19, The rotation speed of the drive motor 4 is controlled based on the calculation result by the calculation control device 18 according to the welding bead height that changes for each stack so that the speed is high at the layer weld and slows as it approaches the final layer. On the other hand, the welding control device 20
While controlling the speed of the welding wire feeding motor 14 so that the welding wire 13 feed speed set and input from the operation panel 19 is detected, the arithmetic and control unit 18 detects the height of the welding surface 2 and one rotation of the round steel 1. Round steel 1 calculated based on signals
The torch height adjusting motor 16 is controlled so as to automatically raise the welding torch 15 by the height of the raised welding bead every 1 rotation of the above, and the distance between the welding surface 2 and the tip of the welding torch 15 is kept constant.

Further, when welding is started and a slag removing command is output from the arithmetic and control unit 18, the automatic slag removing machine 21 is moved up and down with the shaft 22 as a fulcrum by the slag removing machine mount 23 by an elevating means (not shown). Then, the copying roller 26 is brought into contact with the copying ring 25 inserted into the round steel 1. Then, the slide base 27 is moved forward by the air cylinder 24 to bring the tip of the chisel 31 of the air striking type chipping hammer 28 into contact with the welding surface 2 so that the weight 30 is attached to the welding surface 2 via the wire 29. By connecting and press-contacting with a predetermined load, the slag generated on the welding surface 2 of each stack is automatically removed by following the unevenness of the welding surface 2 and the change of the welding diameter.

Therefore, the rotation speeds of the round steels 1 and 1 are controlled so that the welding speed becomes constant according to the welding bead height which changes for each stack, and moreover, the welding bead height which changes for each stack. The height of the welding torch 15 is controlled so that the distance between the welding surface 2 and the welding torch 15 is always constant, and the slag generated on the welding surface 2 at each stacking is uneven by the automatic slag remover 21. In addition, the butt welding of the round steels 1 and 1 can be carried out by continuous automatic welding in accordance with the change of the welding diameter. In the present embodiment, the groove shape of the welded portion is H-shaped, but X
Regardless of the shape of the die, K shape, etc., the rotation speed of the round steel may be controlled so that the welding conditions are constant depending on the shape of the groove.

[0019]

As described above, according to the continuous automatic welding apparatus of the present invention, the constant welding speed and the constant distance between the welding surface and the welding torch can be maintained, and the unevenness of the welding surface 2 and the welding diameter can be maintained. Since the slag generated on the welded surface of each stack can be automatically removed following changes, it becomes possible to continuously and automatically perform butt welding of round steel under constant welding conditions. It can contribute to improvement.

[Brief description of drawings]

FIG. 1 is an overall schematic view of a round steel butt continuous automatic welding apparatus of the present invention.

FIG. 2 is a schematic view of a rotating device for rotating a round steel, (a)
The figure is a front view, and the figure (b) is a plan view.

FIG. 3 is an explanatory view of a welding torch portion, in which (a) is a front view and (b) is a side view.

FIG. 4 is a schematic view of an automatic slag removing device, in which (a) is a plan view and (b) is a front view.

5A and 5B show a chisel tip shape of a chipping hammer. FIG. 5A is a front view of an example of the present invention, and FIG. 5B is a front view of a conventional shape.

[Explanation of symbols]

 1 Round Steel 2 Welding Surface 3 Round Steel Rotating Device 4 Drive Motor 5 Reducer 6 Drive Shaft 7 Drive Rotating Roller 8 Rotating Free Roller 9 Pinch Roll 10 Rotation Detector 11 Gas Shield Arc Welder 12 Welding Power Supply 13 Welding Wire 14 Welding Wire Feed motor 15 Welding torch 16 Torch height adjusting motor 17 Weld bead height detector 18 Arithmetic control device 19 Operation panel 20 Welding control device 21 Automatic slag remover 22 Copy shaft 23 Slag remover stand 24 Air cylinder 25 Copying ring 26 Copying Roller 27 Slide Stand 28 Chipping Hammer 29 Wire 30 Weight 31,41 Chisel

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Mitsuo Somae 1850 Minato, Wakayama, Wakayama Sumitomo Metal Industries, Ltd. Wakayama Works (72) Norio Uchida 1-17, Fuso-cho, Amagasaki, Hyogo Sumikin Welding Kogyo Co., Ltd. (72) Inventor Kazuya Inui 1-17 Fuso-cho, Amagasaki City, Hyogo Sumikin Welding Co., Ltd. (72) Inventor Hiroshi Fujita 1850 Minato, Wakayama, Wakayama Sumikin Plant Technos Co., Ltd.

Claims (2)

[Claims] 1. A welding torch height adjusting mechanism added to a welding machine, and a butt portion of a round steel, in a device for continuously and automatically welding a butt portion while rotating the round steel by a welding machine having a welding wire automatic feeding function. A bead height detector disposed above, a round steel rotation detector, a rotation speed control function added to the round steel rotating device, and an automatic slag remover for pressing the chipping hammer into the welded portion with a predetermined load, Based on the bead height input from the bead height detector and the rotation detector, the rotation speed of the round steel, and the welding conditions set and input from the operation panel, the welding torch height and rotation speed for each rotation of the round steel. And a welding control device for controlling the welding torch height adjusting mechanism and the round steel rotating device to control the welding torch height and rotation speed for each revolution of the round steel calculated by the computing unit. Characteristic round steel bump Automatic continuous welding equipment. 2. A slide stand which has an air cylinder and a copying roller which comes into contact with a copying ring inserted into a round steel, and which is moved forward and backward by the air cylinder, on a slag removing machine stand having a copying shaft at a rear portion. Connect the weight to the chipping hammer that can be moved forward and backward through the wire,
A round steel butt continuous automatic welding device according to claim 1, wherein a predetermined load is applied.