JPH11264522A - Underwater welding nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a stable cavity part when lap fillet weld is executed. SOLUTION: In an underwater welding nozzle, a cylindrical water curtain W7 is formed by curtain water W injected through an annular water curtain outlet 18 of a nozzle 11 and a cavity part is formed on the inner side of the water curtain by shield gas G flowing to the inner side of the water curtain. a tip surface 31 of the nozzle is inclined by an angle β with a plane 33 orthogonal to an axis 32 of the nozzle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a barrier (barrier).
The present invention relates to a submerged welding nozzle for flowing a shielding gas inside a cylindrical water curtain constituting the above, and forming a cavity inside the water curtain, particularly to a submerged welding nozzle for overlapping fillet welding.

[0002]

2. Description of the Related Art While a trumpet-shaped water curtain is formed by curtain water ejected from an annular water curtain outlet of a nozzle, a local cavity is formed inside the water curtain by a shielding gas flowing inside the water curtain. In addition, there has been proposed an underwater welding nozzle configured to remove water from the vicinity of an arc or a molten pool.

[0003]

However, as shown in FIG. 3, two base materials 58, 5 stacked so as to form a step.
9, when the overlap fillet 71 is overlap-filled and the nozzle 11 is gripped so that the target welding angle α is 45 ° to 50 °, the water curtain W extending from the nozzle 11 to the lower surface of the one base material 58 There is a large difference between the length A2 of the 'water curtain W' extending from the nozzle 11 to the lower surface of the other one of the base materials 59 (A3> A2), and it is difficult to form a stable cavity. become.

The present invention has been made in order to solve such a problem, and when performing fillet welding,
It is an object of the present invention to provide an underwater welding nozzle capable of forming a stable cavity.

[0005]

In order to achieve the above object, the underwater welding nozzle according to the present invention forms a cylindrical water curtain by using curtain water jetted from an annular water curtain outlet of the nozzle. In a submerged welding nozzle in which a cavity is formed inside the water curtain by the shielding gas flowing inside the curtain, the tip surface of the nozzle is inclined by β with respect to a plane orthogonal to the axis of the nozzle. There is a feature.

As described above, by inclining the tip end surface of the nozzle by β with respect to a plane perpendicular to the axis of the nozzle, when performing overlap fillet welding, the nozzle is aimed at an angle α of 45 °. By gripping so as to be about 50 °, the length A2 from the nozzle to the lower surface of one base material and the length A3 from the nozzle to the lower surface of the other base material can be made substantially the same.

Here, the inclination angle β of the nozzle tip surface is 10
° to 30 ° is desirable.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. The underwater welding nozzle 10 in FIG. 1 is an underwater welding nozzle for lap fillet welding, and includes a welding torch 41.
And the nozzle 11 attached to the tip of the torch 41. The tip surface 31 of the nozzle 11 is the nozzle 1
It is inclined by β with respect to a plane 33 orthogonal to one axis 32. This inclination angle β is desirably 10 ° to 30 °.

The tip 11A of the nozzle 11 has a double structure of an inner cylinder 12 and an outer cylinder 13, and an annular gap 14 formed therebetween has an annular rectifying chamber 16 having a partition wall 15. Is in communication with Curtain water W supplied to the flow straightening chamber 16 from a water supply pipe (not shown) attached to the outer cylinder 13 is straightened while flowing over the partition wall 15 and into the gap 14 so that the flow velocity becomes uniform. ing.

The jetting portion 19 to which the gap 14 is connected has a flat trumpet-shaped tubular shape, and is composed of a depression 20 provided on the end surface of the outer tube 13 and a tapered surface 22 provided on the back surface of the flange portion of the inner tube 12. Have been. The gap of the ejection part 19 gradually narrows as approaching its outlet, that is, the water curtain outlet 18. The slit interval of the water curtain outlet 18 is desirably 0.5 to 1.0 mm.

Further, a shield gas passage 29 is provided between the nozzle 11 and the welding torch 41, and the welding torch 4
The shield gas G supplied to the shield gas passage 29 from the plurality of holes 43 provided radially at the front end portion 42 of the first unit 42 is supplied to the inside of a water curtain (not shown) through the shield gas passage 29, and is supplied to the inside of the water curtain. A local cavity is formed.

On the other hand, as shown in FIG. 1, a check valve 62 is attached to the tip of a copper drain pipe 61 connected to the root (rear part) of the shield gas passage 29, and a welding torch 41 is provided.
The water remaining inside and inside the nozzle 11 or the water that has entered the welding torch 41 and the inside of the nozzle 11 is discharged. Inside the welding torch 41 and the nozzle 11
The moisture and water in the inside are discharged accompanying the shielding gas flowing through the drain pipe.

Accordingly, the underwater welding nozzle 10 can be used in water in either a downward position or an upward position. In FIG. 1, reference numeral 44 denotes a chip, and reference numeral 45 denotes a welding wire. As shown in FIG. 2, when the overlapped portion 71 of the two base materials 58 and 59 overlapped so as to generate a step, the target fill angle α is 45 ° to 50 °. When the nozzle 11 is held in such a way that
Length A2 of the water curtain W 'reaching the lower surface of the nozzle 11 and the nozzle 11
, The length A3 of the water curtain W 'from the bottom surface of the other one of the base materials 59 becomes substantially the same, and a stable hollow portion can be formed.

[0014]

As described above, according to the present invention, the nozzle tip surface of the underwater welding nozzle is inclined by β with respect to a plane perpendicular to the axis of the nozzle. Is gripped so that the welding target angle α is 45 ° to 50 °, the length A2 of the water curtain W ′ from the nozzle to the lower surface of one of the base materials, and the lower surface of the other base material from the nozzle to the water curtain W ′. The length A3 of the reaching water curtain W 'becomes substantially the same, and a stable hollow portion can be formed.

[Brief description of the drawings]

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

FIG. 2 is an explanatory diagram showing a use state of a submerged welding nozzle according to the present invention.

FIG. 3 is an explanatory diagram showing a use state of a conventional underwater welding nozzle.

[Explanation of symbols]

Reference Signs List 10 Underwater welding nozzle 11 Nozzle 18 Water curtain outlet 31 Nozzle tip surface 32 Nozzle axis 33 Flat plane G Shield gas W Curtain water W 'Water curtain

Continuing from the front page (72) Nobuo Kitamura, No. 1 Kumoide Kokancho, Tsu-shi, Mie Japan Nippon Kokan Co., Ltd., Tsu Research Center (72) Inventor Katsumi Tonomori No. 1, Kumozu Kokan-cho, Tsu-shi, Mie Pref. Inside the Tsu Research Center Co., Ltd. (72) Katsumi Nishida, Inventor Katsumi Nishida 1 in Kumotsu Kokancho, Tsu-shi, Mie Nippon Kokan Co., Ltd. Inside the Tsu Research Center in Tsukuba Co., Ltd. (72) Inventor Yutaka Ono 1 Yawata Kaigandori, Ichihara-shi, Chiba Mitsui Engineering & Shipbuilding Co., Ltd.

Claims (2)

[Claims] 1. A cylindrical water curtain is formed by curtain water jetted from an annular water curtain outlet of a nozzle, and a hollow portion is formed inside the water curtain by a shield gas flowing inside the water curtain. An underwater welding nozzle according to claim 1, wherein the tip surface of the nozzle is inclined by β with respect to a plane perpendicular to the axis of the nozzle. 2. The inclination angle β of the nozzle tip surface is 10 ° to 3 °.
The underwater welding nozzle according to claim 1, wherein the angle is 0 °.