JP3233741B2 - Upward position welding apparatus and method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a upward position welding apparatus and method by gas shielded consumable electrode arc welding.

[0002]

In a conventional gas shielded consumable electrode arc welding upward position welding means, the welding wire and in the upward Ri Contact so as to perform welding from the bottom surface of the base material, welding conditions are the welding current 140 ~ 220A, arc voltage 18 ~ 26
V, welding speed 200 to 600 mm / min or less, CO ₂ gas or Ar + CO ₂ mixed gas is used as the shielding gas, and the welding wire is a solid wire or a flux-cored wire. The range of construction conditions is narrow. This is <br/> Me All welding which shall transfer in a direction opposite to the direction upward position welding is acting molten metal gravity, also Without welded under appropriate welding conditions,
Many weld defects will occur in the weld bead. Therefore, upward welding is not widely applied except in cases where construction is unavoidable. However, in large structures such as ships and bridges, the members are large and difficult to flip and move.
In order to reduce man-hours and costs, upward welding is applied.

[0003] However, there is a disadvantage that the welding speed of the upward position welding is significantly lower than that of the downward position welding. Therefore, in order to improve this disadvantage, when welding at a constant wire feed speed for a fixed time, if the welding speed is increased, the amount of welding per unit length is reduced and the bead width is narrowed, so the welding speed is increased. It is necessary to increase the wire feeding speed and the welding current in order to secure a proper welding amount by welding. However, in a region where the welding current is high, the weld bead becomes discontinuous, and a dripping phenomenon of the weld bead occurs. This phenomenon can be presumed to be caused by the balance between gravity and surface tension, but details are often unknown. When the welding speed is higher (more than 1500 mm / min), a humping bead is easily generated. In order to increase the speed of the upward welding, it is important to take measures to prevent the welding bead from dripping and humping.

[0004]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and it is possible to achieve a high speed welding in an upward posture, and to provide a continuous welding without dripping or humping. It is an object of the present invention to provide an apparatus and a method for upward welding in which a good weld bead can be obtained.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an upward welding apparatus according to the present invention comprises a welding torch.
Guide the welding wire and
Connected to the conduit cable to feed the welding wire
Oscillating pipe, and the oscillating pipe is
At a position facing the electromagnetic coil attached to the welding torch.
A permanent magnet can be attached and fitted to the above electromagnetic coil
The iron core inserted is placed so as to face the permanent magnet.
The electromagnetic coil is connected to the welding power source via a pulse oscillator.
It is characterized by being connected . In addition, the present invention
For the orientation welding method, a welding wire is created inside the welding torch.
Extend the welding wire from the contact tip at the tip
Oscillating pipe connected to conduit cable
And the electromagnetic pipe attached to the welding torch
A permanent magnet provided at a position facing the coil, and the permanent magnet
An iron core inserted into the electromagnetic coil so as to face the
Pulse oscillation interposed between the electromagnetic coil and welding power source
The welding wire is oscillated using a welding device
When performing upward welding while controlling the
The cycle of the heat sink and the cycle of the pulsed welding current are synchronized.
It is characterized by that.

[0006]

In the above-described welding apparatus and method for upward posture of the present invention, the welding wire is oscillated to
The bead width is widened and the cross section of the bead is flattened, preventing dripping of the weld bead, and synchronizing the high-speed oscillating cycle of the welding wire with the pulse waveform cycle of the welding current, thereby welding at both ends of the welding wire. The current is increased and a deep penetration is obtained at both ends of the weld bead, preventing dripping and humping of the weld bead.

[0007]

BRIEF DESCRIPTION OF one embodiment of an upward position welding apparatus and method of the present invention will be described drawings, Figure 1 is a schematic view of instrumentation <br/> location according to the invention, FIG 2 is a longitudinal section of the welding torch in the high frequency FIG. 3 is a perspective view of the weld bead in FIG. 1, and FIG.
4 is a waveform diagram of the electrode oscillation period in the present invention , FIG.
(b) is a waveform diagram of a pulse voltage input to the welding power source, and FIG. 5 is an explanatory diagram of a pulse waveform of a welding current and welding conditions in the present invention .

First, in FIG. 1, a base material 1 is fixed to a lower side of a welding jig 2 and a welding torch 3 for performing gas shield consumable electrode type arc welding on a lower surface of the base material is advancing angle 15 ° or receding angle 15 °. The welding wire 4 that generates an arc 5 between the tip of the welding torch 3 and the base material 1 and forms a welding bead 6 projects from the tip of the welding torch 3. A pair of electromagnetic coils 7a and 7b for oscillating the welding wire 4 is attached to the side of the welding torch 3, and a conduit cable 8 connected to a wire reel 9 is connected to the rear end, and Ar + 20% CO ₂ or 100% CO
_Two shielding gases 10 are also supplied. Further, a welding power source 11 is connected to the welding jig 2 and the welding torch 3, a wire oscillating lead 13 of the pulse oscillator 12 is connected to the electromagnetic coils 7 a and 7 b, and a pulse current lead 14 is connected to the welding power source 11. It is connected.

Next, the wire oscillating mechanism of the welding torch 3 will be described with reference to FIG. 2. An oscillating pipe 15 is connected to the end of the conduit cable 8, and the permanent magnets 16a, 16b are located at positions facing the electromagnetic coils 7a, 7b.
Are mounted respectively, and the electromagnetic coils 7a, 7
The iron cores 17a and 17b fitted in the b are opposed to the permanent magnets 16a and 16b, and the tip of the oscillating pipe 15 is connected to a contact tip 18 which is in contact with the tip area of the welding wire 4. I have.

In such an apparatus, the pulse oscillator 1
Frequency output from 2 f: a pulse equal the peak time T _p and the base time T _b in 10～50Hz, the electromagnetic coil 7a of the welding torch 3 through the wire Oscillating lead wire 13, is supplied to 7b, the permanent Magnets 16a, 16b
Oscillate pipe 15 reliably oscillates left and right according to the pulse frequency, whereby welding wire 4 oscillates left and right with an oscillating width w, as shown in FIG. A weld bead 6 having a flat bead cross section with a bead width is formed. The pulse waveform sent from the pulse oscillator 12 to the welding power source 11 via the pulse current lead wire 14 is
And the welding current is output. At this time, the frequency f _I of the welding current is 2 times the oscillation frequency f so that the welding current becomes a peak current at both ends of the oscillation of the welding wire 4.
That is, f _I : 20 to 100 Hz, and the welding current and the oscillating waveform are in phase. Note that the waveforms of the oscillation frequency f and the welding current frequency f _I are as follows.
As shown in FIG. Also, the oscillation frequency f: 10H
FIG. 5 shows pulse waveforms of welding current and welding conditions when three kinds of experiments of z, 30 Hz, and 50 Hz were performed.

Thus, according to this apparatus and method, the welding bead 6 is formed by oscillating the welding wire 4 in the upward position.
The bead width is wider than that of a normal straight wire, and deep penetration is obtained at both ends of the weld bead 6 by synchronizing the pulse period of the welding current with the oscillation period, spatter is reduced, and stable welding can be performed. Thereby, the transfer of the droplet is stabilized, and the dripping and humping of the weld bead 6 can be prevented. As a result, in the upward position welding, a good weld bead 6 that is continuous and free from defects has a welding speed of 1500 mm / min or more. There is a possibility that it can be obtained in a high-speed region, and it is possible to achieve a higher speed of upward welding.

[0012]

In short , the upward-position welding apparatus of the present invention and
According to fine method, in performing an upward position welding from <br/> in gas shielded consumable electrode arc welding, the welding wire is oscillating at a high speed, to synchronize the period of the cycle and pulsed welding current it makes it possible to achieve a speed of upward position welding, dripping or humping consecutive good weld bead has no obtain Luca et al., the present invention is the extremely valuable industrial.

[Brief description of the drawings]

1 is a schematic diagram of the upward position welding apparatus as an embodiment of the present onset bright.

FIG. 2 is a longitudinal sectional view of the welding torch in the above.

FIG. 3 is a perspective view of a welding bead in FIG. 1;

FIG. 4 (a) is a waveform diagram of an electrode oscillation period in the method of the present invention using the above-described apparatus, and FIG. 4 (b) is a waveform diagram of a pulse voltage input to a welding power source.

FIG. 5 is an explanatory diagram of a pulse waveform of welding current and welding conditions in the above method.

[Explanation of symbols]

 Reference Signs List 1 base material 2 welding jig 3 welding torch 4 welding wire 5 arc 6 welding bead 7a, 7b electromagnetic coil 8 conduit cable 9 wire reel 10 shielding gas 11 welding power supply 12 pulse oscillator 13 wire oscillating lead wire 14 pulse current lead wire 15 Oscillating pipe 16a, 16b Permanent magnet 17a, 17b Iron core 18 Contact tip

Continuation of front page (72) Inventor Takayuki Kono 5-717-1 Fukahori-cho, Nagasaki-shi Mitsubishi Heavy Industries, Ltd. Nagasaki Research Laboratory (56) References JP-A-60-6275 (JP, A) JP-A-51- 143542 (JP, A) JP-A-60-18680 (JP, A) JP-A-2-11276 (JP, A) JP-B-59-9270 (JP, B2) JP-B- 50-23366 (JP, B1) (58) Field surveyed (Int.Cl. ⁷ , DB name) B23K 9/173 B23K 9/02 B23K 9/09 B23K 9/30

Claims (2)

(57) [Claims] 1. A welding torch for guiding a welding wire.
The welding wire from the contact tip
Oscillate pipe connected to conduit cable
The oscillating pipe is attached to the welding torch.
Permanent magnet is mounted at the position facing the
And the iron core inserted into the electromagnetic coil is
The electromagnetic coil is disposed so as to face the
Connected to a power supply via a pulse generator.
An upward-facing welding device. 2. A welding wire guided inside a welding torch.
To feed the welding wire from the contact tip at the tip
An oscillating pipe connected to the conduit cable,
The oscillating pipe is an electromagnetic coil attached to the welding torch.
And a permanent magnet provided at a position facing the
An iron core inserted into the electromagnetic coil so as to face each other,
A pulse oscillator interposed between the electromagnetic coil and the welding power source
Oscillating the above welding wire using a welding device having
When performing the upward position welding while
Of the welding cycle and the cycle of the pulsed welding current.
And an upward-facing welding method.