JP2011098356A - Stand-facing posture welding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stand-facing posture welding apparatus which is made applicable to the butt-welding of high-tensile steel plates while attaining high production efficiency, and then allows the butt-arc welding in the stand-facing posture without causing any oxidation of a weld metal or any defect such as a blow-hole. <P>SOLUTION: The stand-facing posture welding apparatus includes: a welding torch 3 for feeding a welding wire 2 into an I-shaped groove Wb formed between end faces Wa, Wb of a pair of thick steel plates W, W in the stand-facing posture; a truck 5 and a slide unit 6 for moving the welding torch 3 along the I-shaped groove Wb; a controller 20 for sequentially laminating a weld metal 2A while reciprocating a fore end portion 2a of the welding wire 2 to be fed from the welding torch 3 within the I-shaped groove Wb by vertically moving the welding torch 3 by them and controlling the wire feed amount; a nozzle 8 for feeding shield gas into the I-shaped groove Wb from the outer side of the I-shaped groove Wb; and a gas receiver 10 which is attached to the welding torch 3 to cover the I-shaped groove Wb from the welding torch 3 to the layered weld metal 2A. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vertical position welding apparatus used to arc-weld end faces of a pair of steel plates facing each other to form an I-shaped groove in a vertical position.

Conventionally, butt arc welding in the vertical posture of a pair of steel plates as described above is generally employed in fields such as shipbuilding and bridges.
In recent years, steel plates used in such structures as shipbuilding and bridges have been tending to become thicker as the structure becomes larger, but in butt arc welding in a vertical posture between thick steel plates. If the width of the I-shaped groove between the end faces is set to a width that is generally referred to as a narrow groove (a width in which a welding torch can be inserted), a large amount of weld metal is used, and production efficiency is increased. It is not good, and a high-strength steel plate that dislikes large heat input cannot be used as a thick steel plate.

As a welding technique made to eliminate these disadvantages, for example, there is a vertical posture welding method disclosed in Patent Document 1.
In this vertical position welding method, the width of the I-shaped groove formed between the end faces of a pair of thick steel plates in a vertical position is set to be narrower than the diameter of the welding torch, and then this narrow I-shaped position is opened. Only the welding wire sent from the welding torch is inserted diagonally from above, and the welding torch is swung up and down along the thick steel plate to reciprocate the tip of the welding wire in the thickness direction. The weld metal is laminated in the I-shaped groove.
At this time, in order to prevent the occurrence of defects such as oxidation and blowholes in the weld metal, a shielding gas is injected into the I-shaped groove from a nozzle provided integrally with the welding torch.

Japanese Unexamined Patent Publication No. 2007-69231

In the vertical position welding method described above, the width of the I-shaped groove formed between the end faces of a pair of thick steel plates is set to be narrower than the diameter of the welding torch, so the amount of weld metal used is significantly reduced. As a result, the production efficiency can be improved and it can be applied to butt arc welding of high-tensile steel sheets.
However, in the above-described vertical position welding method, the amount of shield gas supplied into the I-shaped groove is inevitably limited due to the narrow width of the I-shaped groove. How to prevent leakage of shielding gas contained in the container and maintain the amount of gas necessary for shielding has been a conventional problem.

  The present invention has been made by paying attention to the above-described conventional problems, and it can be applied to butt welding of high-strength steel sheets as well as improving production efficiency. An object of the present invention is to provide a vertical position welding apparatus capable of performing butt arc welding in a vertical position without causing defects such as oxidation and blowholes in a metal.

  The invention according to claim 1 of the present invention includes a pair of steel plates having a welding torch for feeding a welding wire and forming an I-shaped groove having a width narrower than the diameter of the welding torch, for example, a thickness of 20 mm or more. A vertical position welding apparatus that arc-welds end-faces facing each other of a sheet steel plate, elevating means for moving the welding torch along the I-shaped groove in the vertical direction, and a welding torch by the elevating means By moving up and down and controlling the amount of wire delivered from the welding torch, the tip of the welding wire delivered from the welding torch is reciprocated in the thickness direction of the steel plate within the I-shaped groove, Control means for sequentially laminating weld metal in the I-shaped groove, a gas supply part for supplying a shielding gas into the I-shaped groove from the outside of the I-shaped groove, and at least the welding torch welding A gas receiver that covers the I-shaped groove from the punch to the laminated weld metal is provided, and the vertical position welding apparatus having this configuration is a means for solving the above-described conventional problems It is said.

In this case, it is desirable to use a copper object that easily releases heat and is easy to process for the gas receiver, and it can be attached to the welding torch using a fixing member such as a screw or a belt.
As the shielding gas, CO ₂ gas can be used, and Ar gas or a mixed gas of CO ₂ and Ar can be used.

  In the vertical position welding apparatus having such a configuration, since the gas receiver covering the I-shaped groove from the welding torch to the laminated weld metal is attached to the welding torch, the welding torch and the laminated weld metal are disposed between. Therefore, the amount of shielding gas leaking from the gas can be suppressed, and therefore, the amount of gas necessary for the shielding can be maintained in the I-shaped groove.

  In the vertical posture welding apparatus according to claim 2 of the present invention, the gas receiver has a cover portion that covers the I-shaped groove above the welding torch. It is possible to prevent foreign matters such as spatter from scattering from the shape groove.

  In the vertical position welding apparatus according to claim 3 of the present invention, the gas receiver is configured to include a bead accommodating portion that accommodates a weld bead placed on the I-shaped groove, and in this case, The amount of leakage of the shield gas that has entered the I-shaped groove is reduced to the extent that a gap is less likely to occur between the gas receiver and the pair of steel plates.

The vertical position welding apparatus according to claim 4 of the present invention is configured such that the bead accommodating portion of the gas receiver is provided with a heat-resistant cloth that contacts the pair of steel plates that form the I-shaped groove.
In this case, the heat resistant cloth may be made of a fiber having excellent heat resistance such as an aramid fiber, a polyimide fiber, a polyphenylene sulfide fiber, a glass fiber or a PEEK (polyether ether ketone) fiber.

  In the vertical position welding apparatus having such a configuration, if the heat-resistant cloth is attached to the back side of the bead housing portion, even if there is unevenness in the thickness direction between the pair of steel plates, The heat-resistant cloth absorbs the gap generated between the pair of steel plates, and as a result, the leakage amount of the shield gas from the I-shaped groove can be further reduced.

  In the vertical posture welding apparatus according to claim 5 of the present invention, the heat resistant cloth is configured to extend downward from an end portion of the bead accommodating portion, and in this case, the heat resistant cloth is accommodated in the bead. As in the case of pasting on the back side of the part, the leakage amount of the shield gas from the inside of the I-shaped groove can be further reduced.

At this time, for example, if a notch is formed in the lower end edge of the heat resistant cloth, the lower end edge side of the heat resistant cloth follows the weld bead, so that a gap is less likely to occur between the heat resistant cloth and the weld bead. The leakage amount of the shield gas from the inside of the shape groove can be further reduced.
Further, if a reinforcing body such as a thin steel plate is provided on the surface side of the heat-resistant cloth facing away from the pair of steel plates, the heat-resistant cloth extending downward from the end portion of the bead housing portion has an appropriate rigidity. In this case, it is desirable to form a notch in the lower end edge of the reinforcing body.

  Since the vertical position welding apparatus according to claim 1 of the present invention has the above-described configuration, it can be applied to butt welding of high-strength steel sheets, as a matter of course, improving production efficiency. In addition, a very excellent effect is achieved that it is possible to perform butt arc welding in an upright position without causing defects such as oxidation and blowholes in the weld metal.

  Since the vertical position welding apparatus according to claim 2 of the present invention has the above-described configuration, foreign matter such as spatter can be prevented from scattering from the I-shaped groove.

  In the vertical position welding apparatus according to claim 3 of the present invention, since the above-described configuration is adopted, it is difficult for a gap to be formed between the gas receiver and the pair of steel plates, and the shield gas entering the I-shaped groove is formed. The amount of leakage can be suppressed to a smaller extent, and the vertical position welding apparatus according to claims 4 and 5 of the present invention has the above-described configuration, and therefore the unevenness in the thickness direction between the pair of steel plates is the cause. It is possible to absorb the gap, and as a result, it is possible to further reduce the leakage amount of the shield gas from the inside of the I-shaped groove.

It is side surface explanatory drawing in the welding operation condition of the standing posture welding apparatus which concerns on one Example of this invention. It is plane explanatory drawing of the standing posture welding apparatus shown in FIG. FIG. 2 is an enlarged perspective view illustrating a part of the welding torch of the vertical posture welding apparatus in FIG. 1. It is a whole perspective explanatory drawing which shows simply the welding operation condition of the standing posture welding apparatus in FIG. FIG. 2 is an enlarged perspective explanatory view showing a gas receiver of the vertical position welding apparatus in FIG. 1. Expansive perspective view (a), (b), (d) showing a gas receiver of a vertical position welding apparatus according to another embodiment and a partially enlarged perspective explanatory view (c) showing a heat-resistant cloth of the gas receiver according to another configuration example ).

Hereinafter, the present invention will be described with reference to the drawings.
1 to 5 show an embodiment of a vertical posture welding apparatus according to the present invention.

  As shown in FIGS. 1 and 2, this vertical position welding apparatus 1 is an apparatus for arc welding abutting end surfaces Wa and Wa of a pair of steel plates W and W in a vertical position with each other. A welding torch 3 having a diameter of φ20 mm is provided for feeding only the welding wire 2 fed from the feeding device to an I-shaped groove Wb formed between the end faces Wa of the pair of steel plates W, W.

In this case, the steel plate W is a steel plate employed for large structures such as shipbuilding and bridges, and is a thick steel plate having a thickness of 20 mm or more.
The groove gap G of the I-shaped groove Wb formed between the end faces Wa and Wa of the pair of thick steel plates W and W is preferably set as narrow as possible so as to keep heat input during welding low. Then, since only the welding wire 2 has only to be inserted into the I-shaped groove Wb, the width dimension of the welding wire 2 is set to 8 mm, which is slightly wider than, for example, φ1.6 mm.

The welding torch 3 is disposed on a rail 4 installed in the vertical direction along the thick steel plates W, W, for example, on a carriage (elevating means) 5 that travels in a rack and pinion system.
In this embodiment, the welding torch 3 is disposed at a predetermined angle θ with respect to the plate thickness direction (horizontal direction) so that the welding wire 2 to be fed is inserted into the I-shaped groove Wb obliquely from above. 5 is attached so as to be swingable in the vertical direction (arrow direction in FIG. 1) through a slide unit 6 which constitutes a lifting means together with the carriage 5.
As shown in FIG. 3, the welding torch 3 is integrally provided with a nozzle 8 for injecting a shielding gas into the I-shaped groove Wb.

In addition, the vertical posture welding apparatus 1 includes a control unit 20. As shown in FIG. 4, the control means 20 swings the welding torch 3 up and down by the slide unit 6 while moving the carriage 5 in the upward direction, and controls the wire feed amount from the welding torch 3. As a result, the tip of the welding wire 2 fed obliquely downward from the welding torch 3 is reciprocated in the plate thickness direction within the I-shaped groove Wb, so that the weld metals 2A are sequentially laminated.
That is, the welding operation can be performed by inserting only the welding wire 2 into the I-shaped groove Wb of the narrow groove gap G without moving the welding torch 3 in the thickness direction. Yes.

Further, the vertical position welding apparatus 1 includes a gas receiver 10 that is attached to the welding torch 3 and moves together with the welding torch 3.
The gas receiver 10 is made of copper. As shown in FIG. 5, a plate-shaped receiving body 11 covering the welding torch 3 and the I-shaped groove Wb up to the laminated weld metal 2 </ b> A is integrally formed with the receiving body 11. The formed connecting cylinder 12 and a cover portion 13 which is formed integrally with the receiving body 11 and covers the I-shaped groove Wb above the welding torch 3 are inserted, and the welding torch 3 is inserted into the connecting cylinder 12. By fixing with a screw 9, the welding torch 3 is attached.

  In this case, the receiving body 11 is formed with a bead accommodating portion 14 extending downward from the base of the connecting cylinder 12 and accommodates the weld bead B placed on the I-shaped groove Wb during welding. ing.

  Reference numeral 7 in FIGS. 1 and 2 is a backing plate made of a heat-resistant member located on the opposite side to the wire insertion side of the I-shaped groove Wb, and closes the back-side opening of the I-shaped groove Wb to weld metal 2A. Is prevented from leaking. Here, the opening at the lower end of the I-shaped groove Wb is normally closed with another thick steel plate W or weld metal 2A.

  In the vertical position welding apparatus 1 having such a configuration, first, a pair of thick steel plates W and W are erected so that an I-shaped groove Wb having an extremely narrow groove gap G is formed between the end faces Wa and Wa. In addition to installing the vertical position welding device 1 and the backing plate 7 at predetermined positions, and setting the welding torch 3 at a predetermined angle θ with respect to the plate thickness direction (horizontal direction). The tip portion 2a of the welding wire 2 protruding from the welding torch 3 is inserted into the I-shaped groove Wb obliquely from above.

  Next, when energization control is started based on a current value and a voltage value set in advance according to the diameter and length of the welding wire 2, that is, the end surfaces Wa of the thick steel plates W and W from the distal end portion 2a of the welding wire 2. , Wa, when arc welding is started and arc welding is started, melting of each end face Wa, Wa of the welding wire 2 and the pair of thick steel plates W, W starts, and the weld metal is formed in the I-shaped groove Wb. Generation of 2A is started.

As shown in FIGS. 1 and 2, at the stage where arc welding is started in this way, the welding torch 3 is swung up and down by the slide unit 6 while moving the carriage 5 upward, and the control means 20 By controlling the amount of wire delivered from the welding torch 3 by means of this, the tip portion 2a of the welding wire 2 delivered obliquely downward from the welding torch 3 is reciprocated in the plate thickness direction within the I-shaped groove Wb. The weld metal 2A is sequentially laminated.
During this time, a shield gas for protecting the weld metal 2A is injected from the nozzle 8 provided integrally with the welding torch 3 into the I-shaped groove Wb.

Here, in order to reduce the amount of use of the weld metal 2A or to keep the heat input during welding low, the groove gap G of the I-shaped groove Wb is narrowed. Although the gas supply amount is inevitably limited, the gas receiver 10 mounted on the welding torch 3 moves together with the welding torch 3 to form an I shape in a range from the laminated weld metal 2A to the upper side of the welding torch 3. Since the groove Wb is covered, the amount of shielding gas that has once entered the I-shaped groove Wb is reduced, and the amount of gas necessary for the shield is maintained.
That is, butt arc welding in a vertical posture can be performed without causing defects such as oxidation and blowholes in the weld metal 2A.

Further, in this embodiment, since the cover portion 13 covering the I-shaped groove Wb above the welding torch 3 is provided integrally with the main body 11, foreign matter such as spatter is scattered from the I-shaped groove Wb. It can be blocked.
Furthermore, in this embodiment, the bead accommodating portion 14 formed in the receiving body 11 of the gas receiver 10 is adapted to receive the weld bead B placed on the I-shaped groove Wb. The gap between the thick steel plates W and W is less likely to be generated, and as a result, the leakage amount of the shield gas that has entered the I-shaped groove Wb can be reduced.

  As described above, in this embodiment, by forming the bead accommodating portion 14 in the receiving body 11 of the gas receiver 10, the leakage amount of the shield gas from the inside of the I-shaped groove Wb is suppressed. As another embodiment, as shown in phantom lines in FIG. 5, a heat-resistant cloth 15 that is in contact with the pair of thick steel plates W and W forming the I-shaped groove Wb is pasted on the back side of the bead accommodating portion 14. If it does so, even if there is unevenness in the thickness direction between the pair of thick steel plates W, W, the heat-resistant cloth 15 absorbs the gap generated between the receiving body 11 and the pair of thick steel plates W, W. As a result, the leakage amount of the shield gas from the inside of the I-shaped groove Wb can be further reduced.

Further, as another embodiment, as shown in FIG. 6A, the heat-resistant cloth 15 may be attached so as to extend downward from the end portion of the bead accommodating portion 14, and this configuration is adopted. In addition, similarly to the case where the heat-resistant cloth 15 is attached to the back side of the bead housing part 14, the leakage amount of the shield gas from the inside of the I-shaped groove Wb can be further reduced.
At this time, the heat-resistant cloth 15 can be attached to the receiving body 11 using screws 16 or can be attached so as to be sandwiched between the pressing plate 17 and the receiving body 11 as shown in FIG. .

  Thus, when attaching the heat-resistant cloth 15 so as to extend downward from the end portion of the bead accommodating portion 14, if the notch 15 a is formed at the lower end edge of the heat-resistant cloth 15, the lower end edge side of the heat-resistant cloth 15. However, following the weld bead B, a gap is hardly formed between the heat-resistant cloth 15 and the weld bead B. Therefore, the leakage amount of the shield gas from the I-shaped groove Wb can be further suppressed.

  The number of the notches 15a and the places to be formed are not particularly limited. However, when the notches 15a are arranged at one place on the lower edge of the heat-resistant cloth 15, for example, as shown in FIGS. 6 (a) and 6 (b). In addition, it is desirable to form long slits 15a along the ridgeline of the weld bead B. On the other hand, when the slits 15a are arranged at a plurality of locations on the lower edge of the heat-resistant cloth 15, for example, as shown in FIG. As shown, it is desirable to form short cuts 15a symmetrically on both sides of the weld bead B.

  Furthermore, as another example, in the case where the heat-resistant cloth 15 is attached so as to extend downward from the end portion of the bead housing portion 14, as shown in FIG. 6 (d), a pair of thick plates of the heat-resistant cloth 15 is provided. It is good also as a structure which piled up and attached the thin steel plate (reinforcement body) 18 on the surface side facing the steel plate W and the opposite side, and if this structure is employ | adopted, it will be heat-resistant extended below from the edge part of the bead accommodating part 14. Since the cloth 15 has an appropriate rigidity, the cloth 15 can be prevented from curling up and breaking.

  In this case, if the notch 18a is formed at the lower edge of the thin steel plate 18, the lower edge side of the heat resistant fabric 15 together with the thin steel plate 18 follows the weld bead B, and the heat resistant fabric 15 and the weld bead B Since a gap is less likely to be generated between them, the amount of shielding gas leaked from the I-shaped groove Wb can be further reduced.

In the above-described embodiment, the vertical position welding apparatus according to the present invention is used to butt-arc weld the end surfaces Wa, Wa of a pair of thick steel plates W, W having a vertical thickness of 20 mm or more in a vertical position. Although the case has been shown, it is naturally applicable to butt arc welding of steel plates having a thickness of 20 mm or less.
The configuration of the vertical position welding apparatus according to the present invention is not limited to the configuration of the above-described embodiment.

DESCRIPTION OF SYMBOLS 1 Standing posture welding apparatus 2 Welding wire 2a Welding wire tip 2A Welding metal 3 Welding torch 5 Carriage (lifting means)
6 Slide unit (lifting means)
8 Nozzle (gas supply part)
DESCRIPTION OF SYMBOLS 10 Gas receiver 11 Receiver main body 13 Cover part 14 Bead accommodating part 15 Heat-resistant cloth 15a Notch 18 Thin steel plate (reinforcing body)
20 Control means B Weld bead G Groove gap (width of I-shaped groove)
W Thick steel plate (steel plate)
Wa End face of thick steel plate (end face of steel plate)
Wb type I groove

Claims (5)

A vertical position welding apparatus comprising a welding torch for delivering a welding wire, arc welding the end faces facing each other of a pair of steel plates forming an I-shaped groove having a width narrower than the diameter of the welding torch,
Elevating means for moving the welding torch along the I-shaped groove in the vertical direction;
By moving the welding torch up and down by the elevating means and controlling the amount of wire delivered from the welding torch, the tip of the welding wire delivered from the welding torch is moved in the thickness direction of the steel plate within the I-shaped groove. A control means for sequentially laminating the weld metal in the I-shaped groove,
A gas supply unit for supplying a shielding gas from the outside of the I-shaped groove into the I-shaped groove;
A vertical position welding apparatus comprising a gas receiver that is attached to the welding torch and covers at least an I-shaped groove from the welding torch to the laminated weld metal.   The vertical posture welding apparatus according to claim 1, wherein the gas receiver includes a cover portion that covers an I-shaped groove above the welding torch.   The vertical position welding apparatus according to claim 1 or 2, wherein the gas receiver includes a bead accommodating portion that accommodates a weld bead placed in the I-shaped groove.   The vertical posture welding apparatus according to claim 3, wherein a heat-resistant cloth that is in contact with a pair of steel plates forming the I-shaped groove is provided in the bead accommodating portion of the gas receiver.   The vertical posture welding apparatus according to claim 4, wherein the heat-resistant cloth is provided to extend downward from an end portion of the bead housing portion.

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