JPH11264520A - Underwater weld nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To not only discharge a moisture content remaining in weld torch and a nozzle before underwater welding but also arbitrarily discharge water penetrating in the weld torch and the nozzle under underwater welding. SOLUTION: In this underwater weld nozzle, curtain water W is injected through an annual water curtain outlet 18 arranged at a nozzle 11 mounted on a weld torch 41 to form a cylindrical water curtain W'. Meanwhile, shield gas G is injected through a shield gas passage 29 arranged between the weld torch and the nozzle to form a cavity part S at the inside of the water curtain. In this case, a drain pipe 61 having a check valve 62 is connected to the shield gas passage 29.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater welding nozzle provided with a means for removing water remaining or entering water in a welding torch and a nozzle.

[0002]

2. Description of the Related Art Curtain water is ejected from an annular water curtain outlet provided on a nozzle mounted on a welding torch to form a cylindrical water curtain, and a shielding gas provided between the welding torch and the nozzle. A submerged welding nozzle that ejects shielding gas through the passage inside the water curtain and forms a local cavity inside the water curtain to remove water from the arc and around the molten pool and perform arc welding. Proposed.

[0003]

The conventional underwater welding nozzle has no problem in the case of so-called downward welding in which the nozzle is welded downward. However, in the case of so-called upward welding, in which the nozzle is directed upward, the water that has penetrated into the nozzle or the welding torch is sprayed into the cavity as a mist, so that the cavity or arc becomes unstable. This has the problem of adversely affecting the shape of the bead.

The present invention has been made to solve such a problem, and not only can water remaining in a welding torch or a nozzle be discharged before underwater welding,
It is an object of the present invention to provide an underwater welding nozzle capable of discharging water that has entered a welding torch or a nozzle at any time during underwater welding.

[0005]

In order to achieve the above object, a submerged welding nozzle according to the present invention blows out curtain water from an annular water curtain outlet provided in a nozzle attached to a welding torch to form a tube. To form a water curtain,
In a submerged welding nozzle that blows out shielding gas through a shielding gas passage provided between a welding torch and a nozzle to form a cavity inside a water curtain, a drain pipe equipped with a check valve in the shielding gas passage is used. Connected.

[0006] According to this configuration, moisture remaining in the welding torch or the nozzle accompanying the shield gas branched from the drain pipe connected to the shield gas passage into the drain pipe, The water that has invaded the water is drained. Further, since the check valve is attached to the drain pipe, water does not flow back into the nozzle or the welding torch.

Here, it is desirable to connect a drain pipe provided with a check valve at the deepest part of the shield gas passage.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the nozzle 11 attached to the tip of the welding torch 41 has a nozzle tip 11
A has a double structure of the inner cylinder 12 and the outer cylinder 13,
An annular gap 14 formed therebetween is formed by a partition wall 15
Is connected to an annular rectification chamber 16 having

The curtain water W supplied from the water supply pipe 17 attached to the outer cylinder 13 to the flow straightening chamber 16 is straightened while flowing over the partition wall 15 into the gap 14, so that the flow velocity becomes uniform. I have. The gap 14 is connected to a flared tubular outlet 19 whose diameter gradually increases as approaching the nozzle tip. The spouting part 19 is
And a tapered surface 22 provided on the back surface of the flange portion 21 of the inner cylinder 12, and the gap is defined by the outlet of the ejection portion 19, that is, the water curtain. It gradually narrows as it approaches the exit 18.

The slit interval of the water curtain outlet 18 is
0.5 to 1.0 mm is desirable. In the case of downward welding, the angle θ1 of the ejection portion 19 is desirably 55 ° to 65 °. The nozzle 11 is configured such that an inner cylinder cover 27 made of copper is screwed inside the inner cylinder 12 to protect the inner wall surface of the inner cylinder 12 and the end face of the flange portion 21. When spatter or the like adheres to the inner cylinder cover 27, it is replaced with a new inner cylinder cover to prevent disturbance of the shield gas. At this time, the inner cylinder cover 2 having an appropriate inner diameter D
When 7 is selected, there is an advantage that the selection of the shield condition becomes easy.

The nozzle 11 is formed such that the inner diameter of the mounting portion 28 matches the outer diameter of the welding torch 41 so that the nozzle 11 can be mounted on the welding torch 41. Also, the welding torch 41
Gas G supplied from a plurality of holes 43 provided radially at the tip end 42 of the nozzle 11 passes through a shield gas passage 29 provided between the welding torch 41 and the nozzle 11, from the tip of the nozzle 11 to the curtain water. Spouted inside W '.

In the drawing, reference numeral 44 denotes a frustoconical tip mounted on the tip of the welding torch 41, and reference numeral 45 denotes a welding wire. On the other hand, a copper drain pipe 61 is connected to the innermost part of the shield gas passage 29. The drain pipe 61 includes a check valve 62 in the middle thereof. However, when performing upward welding in water,
Curtain water is ejected from an annular water curtain outlet 18 provided at the nozzle tip 11A to form a trumpet-shaped water curtain W ', and a shielding gas G is supplied from the shielding gas passage 29 to the inside of the water curtain W'. It gushes and forms the cavity S inside the water curtain W '.

At this time, a part of the shield gas branches and flows into the drain pipe 61 connected to the shield gas passage 29, and remains in the welding torch 41 and the nozzle 11 along with the shield gas. Moisture is drained. Since the check valve 62 is attached to the drain pipe 61, it is possible to prevent water from entering the nozzle 11 from the drain pipe 61.

[0014]

As described above, according to the present invention, since the drain pipe having the check valve is connected to the shield gas passage in the underwater welding nozzle, it remains in the welding torch or the nozzle before underwater welding. Not only can water be drained, but water that has entered the welding torch or nozzle during underwater welding can be drained at any time.

Therefore, the water remaining in the welding torch or the nozzle or the water that has entered the welding torch or the nozzle is not sprayed into the cavity S in the form of a mist, so A stable cavity can be formed. Further, the arc was stabilized, and a beautiful bead could be continuously formed as in the atmosphere.

Further, according to the present invention, since a drain pipe provided with a check valve is connected to the deepest part of the shield gas passage in the underwater welding nozzle, even in the case of upward welding, it remains in the welding torch or nozzle. It is possible to discharge water that has entered or water that has entered the welding torch or nozzle.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a submerged welding nozzle according to the present invention.

[Explanation of symbols]

11 Nozzle 18 Water curtain outlet 29 Shield gas passage 41 Welding torch 61 Drain pipe 62 Check valve G Shield gas S Cavity W Curtain water W 'Water curtain

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Nobuo Kitamura, No. 1 Kumoido Kokancho, Tsu City, Mie Prefecture Inside the Nippon Kokan Co., Ltd. Tsu Research Center (72) Inventor Katsumi Tonomori 1 Kumotsu Kokancho, Tsu City, Mie Prefecture Address: Nippon Kokan Co., Ltd., Tsu Research Center (72) Inventor Katsumi Nishida 1) Kumoide Kokancho, Tsu City, Mie Prefecture Nippon Kokan Co., Ltd., Tsu Research Center (72) Inventor: Takahiro Irie, Yawata Kaigandori, Ichihara City, Chiba Prefecture No. 1 Mitsui Engineering & Shipbuilding Co., Ltd. Chiba Works Co., Ltd. (72) Inventor Yutaka Ohno 1 No. 1 Mitsui Engineering & Shipbuilding Co., Ltd.

Claims (2)

[Claims] 1. A cylindrical water curtain is formed by jetting curtain water from an annular water curtain outlet provided in a nozzle mounted on a welding torch, and a shielding gas provided between the welding torch and the nozzle. An underwater welding nozzle for discharging a shielding gas through a passage to form a cavity inside a water curtain, wherein a drain pipe having a check valve is connected to the shielding gas passage. 2. The underwater welding nozzle according to claim 1, wherein a drain pipe provided with a check valve is connected to the innermost portion of the shield gas passage.