JPS6049864A - Underwater welding device - Google Patents

Abstract

PURPOSE:To mount easily a casing in the stage of mounting the casing to the material to be welded in water by guiding the gas overflowing from a gas holding skirt to a discharge path to permit observation from above the water without interference. CONSTITUTION:A welding torch 1 is attached to a casing 4 and while a shielding gas is ejected from a welding nozzle 3, the casging 4 is successively sunk into water and is mounted to a part 6 to be welded, by which the periphery of the part 6 and an electrode 2 is maintained in a gaseous atmosphere. The shielding gas overflowing from the bottom surface of a gas holding skirt 8 enters the inside of an outside skirt 12 and is guided via a discharge pipe 13 and a discharge hose 15 to the water surface. The sure observation of the relative position of the material 5 to be welded and the casing 4 from above the water surface is thus made possible without rising of foam around the casing 4 and the mounting of the casing 4 is made easy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an underwater welding device for welding in a gas space provided underwater.

[Technical background of the invention and its problems]

As shown in Fig. 1, conventional underwater welding equipment is designed to prevent the electrode (2) provided in the welding torch (1) from overflowing with water.
Attach the casing (4) to one of the objects to be welded (5) and (5&) while blowing out shielding gas from the welding nozzle (3) provided in advance on the welding torch (1). , the part to be welded (6) and the electrode (2) are kept in a gas atmosphere. In order to maintain a large gas space (7) for retaining a gas atmosphere, a gas retaining skirt (8) is provided throughout the lower part of the casing (4) to surround the welded portion (6). In this case, bubbles from the shielding gas overflowing from the entire lower surface of the gas retaining skirt (8)
) rises around the casing (4) and the workpiece (5).
), (5a), it was difficult to observe the relative position between the casing (4) and the object to be welded (5) +' (5a), making it difficult to attach the casing (4). In addition, with the conventional casing (4), it was not possible to check the attachment status to the object to be welded (5), and welding work for nuclear equipment that required high quality relied on the intuition of experts, resulting in poor reliability. Ta.

[Purpose of the invention]

It is an object of the present invention to provide an underwater welding apparatus in which the position relative to the object to be welded can be observed well when the casing is attached, and the casing can be easily attached.

[Summary of the invention]

In the present invention, the part to be welded underwater is housed in a gas space having the entire gas retaining skirt and kept in a gas atmosphere, but even before the part to be welded is attached to the part to be welded, the part to be welded is inserted into the gas space through the welding nozzle around the electrode. In an underwater welding device equipped with a casing that is attached to a workpiece underwater while supplying shielding gas, the shielding gas overflowing from the lower end of the gas holding skirt does not obstruct observation of the workpiece from above the water. By providing an exhaust passage that guides the weld, the relative position between the casing and the workpiece to be welded can be observed easily, and the casing can be easily attached.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3. In these figures, the same parts as in FIG. 1 are designated by the same reference numerals, and their explanation will be omitted.

Fully insert the welding torch (1) into the casing (4) and insert the electrode (
2) is adjusted in advance with a cage (not shown), then the tightening fittings (11, (11
) to fully secure the welding torch (1). Therefore, if the casing (4) is correctly attached to the workpiece (5), the electrode (
The position 2) will also be placed at the correct aiming position.

(Gas retaining scar of casing (4))
Both f4), (5) when attaching to the workpiece to be welded (5)
) A shield gas exhaust pipe α9 is provided at a position where it does not completely block the observation of the relationship fk'. Of course, the upper part of the outer skirt is airtight except for the exhaust pipe. A distributor a4)"x is provided at the upper end of the exhaust pipe, and the distributor u4) is fixed to the casing (4). One end of the shield gas exhaust hose α is attached to the distributor u4), and the distributor u4) is fixed to the casing (4). The casing (4) is connected to the workpiece (5) by a guide member (not shown), and the other end is exposed to the atmosphere. When a plurality of (two in this case) contacts α contact the object to be welded (5) and conduct electricity.
0 to the casing (4) via the insulator ←η.

The tip of the contact aQ is slightly protruded from the casing (4), and the back is pressed by the spring α, and the other end of the spring is pressed against the cover α.
Hold at 1. The detection monitor (A) is installed at a monitoring position above the water surface, and the left and right contacts (161, the
, connect the cable (2η+121)ffi.

In this case, the cable (21) is inserted through the exhaust hose tt51, pulled out from the distributor I, and wired. Detection monitor, (
Connect the ground side cable (2z) of 2I to the workpiece (5).

Next, when attaching the casing (4) to the object to be welded (5), the operation of which will be explained next, is to submerge the casing (4) in water while blowing out shielding gas from the welding nozzle (3). (5), the part to be welded (6) and the electrode (2)
A gas atmosphere can be maintained around the area. At this time, the shielding gas overflows from the lower surface of the gas retaining skirt (8), but enters the outer skirt a2 and is guided above the water surface by the exhaust pipe (1 and exhaust hose U!19), so the shielding gas flows around the casing (4). There are no air bubbles rising up, and the relative position between the workpiece (5) and the casing (4) can be reliably observed from above the water surface.Therefore, the casing (4) can be easily attached. ) has a contact (Il
19 is provided, and the casing (4) is the workpiece to be welded (5).
If the contactor [161 to 71
7. Since air flows and this is detected by the detection monitor, even unskilled workers can easily confirm that the casing (4) is installed in the correct position. Therefore, highly reliable underwater welding is easily possible.

Another embodiment shown in FIG. 4 has two contacts.

([6) One of the ground side cables (2Z fully connected [7, the detected electricity flows between the solid contacts uo and ue, and the others are implemented as shown in Figures 2 and 3. Similar to the example.

In this way, you can save one wiring cable, and
The same effects as the embodiments shown in FIGS. 2 and 3 can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, when the casing is attached to the object to be welded, shielding gas bubbles are prevented from rising around the casing, so attachment can be done easily and reliably, and there is no underwater monitoring. This not only improves the reliability of welding under certain conditions, but also shortens the construction schedule. In addition, an underwater welding device with extremely high practical value has been obtained, such as being able to quickly perform work under radiation exposure such as nuclear equipment and reducing the exposure dose to the human body.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway elevational view showing a conventional underwater welding device, Fig. 2 is a partially cutaway elevational view showing an embodiment of the underwater welding device of the present invention, and Fig. 3 is a partially cutaway elevational view showing a conventional underwater welding device. − Cross-sectional view along the line,
FIG. 4 is a sectional view showing the main parts of another embodiment. ■... Welding torch 2... Electrode 3... Welding nozzle 4... Casing 5... Welded object 6... Welded part 7... Gas space 8... Gas retaining skirt 12・・・
・Outer scar) 13...Exhaust pipe 15...Exhaust hose 16...Contactor 20...Detection monitor agent Patent attorney Inoue - Male No. 1 Fig. 2 Fig. 3 Fig. 4

Claims (3)

[Claims] (1) In order to keep the part to be welded underwater in a gas space with a gas retaining skirt and to keep it in a gas atmosphere, shielding gas is supplied to the gas space through the welding nozzle around the electrode before it is attached to the part to be welded. In an underwater welding apparatus equipped with a casing that is attached to an object to be welded underwater while supplying the gas, an exhaust gas is used to guide the shielding gas overflowing from the lower end of the gas retaining skirt so that it does not obstruct observation of the object to be welded from above the water. Underwater welding equipment characterized by a biased metal. (2) A patent characterized in that the exhaust passage is formed by an outer skirt that covers the gas retaining skirt, an exhaust pipe provided above the outer skirt, and an exhaust hose that communicates with the exhaust pipe and opens above the water. An underwater welding device according to claim 1. (3) When the casing is attached to the correct position of the workpiece to be welded, the casing is equipped with multiple contacts that contact the workpiece and conduct electricity, and is equipped with a detection monitor that detects the conduction. An underwater welding apparatus according to claim 1 or 2, characterized in that: