JPS6320466Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a gas-shielded arc or plasma welding torch used for underwater heating, welding, fusing, and land-based field welding, and includes a bowl-shaped skirt partition that surrounds the high-temperature space between the torch and base metal. By simply attaching it to the tip of a waterproof welding torch such as TIG, MIG, CO ₂ or plasma, it can be used both underwater and on land in strong winds.

Conventionally, underwater welding using TIG, MIG, CO ₂ , plasma welding, etc. described above has been limited to either a dry method in which the weld area is placed in a chamber, or a water curtain method in which water is jetted out in a conical shape from a nozzle. was.

Simply put, the torch of this invention uses a flexible, elastic bowl-shaped skirt with a stainless steel wire brush on the outer layer attached to the tip of the torch to fill a high-temperature space with shielding gas. When welding underwater, when the gas released from the high-heat space becomes large bubbles and exits into the water, the water immediately flows back into the space, so the gas is continuously released from the narrow water as small bubbles. , which prevents water from flowing backwards. Therefore, it can be applied not only to welding but also to heating and cutting. The inner layer of the bowl-shaped skirt is an aggregate of heat-resistant fibers such as carbon fibers.

In addition, when used for wind-resistant welding on land, these flexible and elastic bowl-shaped skirt partitions have the effect of blocking the wind, and the shielding gas will not be blown away even at sites where strong winds blow. Since it covers the welded area, a good welded area can be obtained.

The structure of this invention will be explained below with reference to the illustrated embodiments.

FIG. 1 shows a state in which underwater welding is being performed using a MIG welding torch 1 which is an embodiment of this invention. In this case, the base material 2 has a ▽-shaped welding groove 2a as shown in the cross section of FIG. 4, and welding is completed in one layer. Therefore, unlike when welding the flat upper surface of the base material 2 as shown in Fig. 2, the groove portion 2a on the upper surface of the base material 2 before welding is concave, and the bead 3 after welding is raised. . Such changes in the height of the base metal are unavoidable in arc welding, but since the outer layer of the torch of this invention is made of elastic stainless steel wire, it adapts well to the changes in height, and the internal gas pressure prevents water from flowing. This prevents the intrusion of gases and turns all released gases into fine bubbles. Note that the partition material 4 will be described in detail later.

The torch 1 of this embodiment is a conventional torch which has been waterproofed and has an annular groove 5 as shown in FIG. Fit the upper edge of 4 into the groove 5.
A nut 7 is tightened to a male thread 6 provided on the inner outer surface of the groove 5, and is clamped and fixed between the outer conical surface 7a of the nut and the conical surface 5a of the outer circumferential inner surface of the groove 5. Annular groove 5
In this case, since it is formed between the diameter-reducing step provided at the tip of the metal cylinder 1a of the torch 1 and the insulating torch jacket cylinder 1b fitted to the metal cylinder 1a, it is manufactured together with the male thread 6. It's easy. However, the method of attaching the partition material 4 to the torch 1 is not limited to the above method.
In short, the connection is almost airtight, and replacement is not troublesome.

In FIG. 2, the welding wire 8 is connected to the power supply guide tube 9.
Since then, gas is only sent out from the shield gas supply pipe 10. The shielding gas may be argon to prevent oxidation of the welding area, or a mixed gas containing carbon dioxide or a small amount of oxygen, and it goes without saying that carbon dioxide alone may be sufficient depending on the purpose. In the case of underwater welding, the inside of the partition member 4 is maintained at a pressure higher than the surrounding water pressure to prevent water from entering. Then, some of the gas flows through the many pores and pores of the partition material 4,
It becomes fine air bubbles from the narrow gap between the lower edge of the partition material 4 and the surface of the base material 2 and escapes into the water. When the shielding gas escapes into the water, it becomes large bubbles and exits into the water, causing the water to flow back at that moment, but when it continuously becomes small bubbles and is dispersed and released, water enters the skirt. Never. Therefore, the partition material 4 of this invention
Water can be completely excluded without sealing the vicinity of the welding part, and the arc 11 between the wire 8 and the base metal 2 can be welded under conditions similar to welding on land. Therefore, in addition to welding, it can also be applied to heating and fusing that require raising the temperature.

Now, the bowl-shaped skirt partition material 4, which is the most distinctive feature of this invention, has a shape suitable for enclosing the high-heat space between the torch and the base material, and its opening edge conforms to the surface of the base material, which has a high resistance change. Fibers that have flexible elasticity that can be deformed, can turn the shielding gas released into the water into fine bubbles in the case of underwater welding, and have a fineness that can sufficiently block wind in the case of welding on land. The outer layer is made of stainless steel wire and the inner wall is an aggregate of heat-resistant fibers, giving sufficient heat resistance and spatter adhesion prevention properties.

The partition member 4 in the embodiment shown in FIG. 2 is for experimental purposes.
The entire circumference is made up of parallel layers of heat-resistant stainless steel wires in the form of a brush. The wires are 0.05-0.3 mm in diameter and arranged in a bowl-shaped brush shape at a density of 200-1000 wires per square centimeter, with the angle between the brush and the base material being 40°-60°. This satisfies the above-mentioned requirements for a skirt-shaped partition material, including shape, elasticity, fineness, etc.
It satisfied the requirements for durability and wind resistance, and the experimental results were also good.
In manual welding, the distance between the torch 1 and the base metal 2 constantly changes, but by setting the angle between the stainless steel wire cup-shaped partition 4 and the base metal at 40° to 60°, the torch 1 moves up and down smoothly, and even if the torch 1 moves up and down about 10 mm above the base metal 2, the opening edge does not float above the base metal 2. Of course, the welder moves the torch 1 up and down about 10 mm above the base metal 2.
The welding is carried out while lightly pressing the part against the side.

Since the above-mentioned thin wire is used as the partition material 4, this stainless steel wire partition material 4 is well protected against vertical displacement of the torch 1, dents caused by the groove 2a of the base material 2, and protrusions of the weld bead 3. In the case of break-in and underwater welding, fine air bubbles mainly come out into the water from the narrow area near the opening edge. Moreover, since the intense arc light weakens as it passes between the wires and exits, there is no need for safety glass, and underwater welding has the advantage of being able to see the bead 3 immediately after welding with the naked eye and judge whether it is good or bad. I have it too. Even when used on land, as described above, the partition material 4 is in close contact with the surface of the base material, so it exhibits a sufficient wind resistance effect, and the shielding gas is not blown away by the wind.

However, as a result of continuing this experiment for a long time, it was found that welding spatters adhered to the inner circumferential surface of the partition member 4, connecting the wires to each other, and gradually losing the brush-like flexibility. If you clean regularly to remove spatter, the wire will break and the wire density will decrease, making it easier for water to enter the welding area. Therefore, the bowl-shaped partition material will need to be replaced after 20 minutes to an hour of welding time. Ta.

Therefore, in order to impart spatter adhesion prevention properties to the bowl-shaped partition material, at least the inner circumferential layer of the bowl-shaped partition material is preferably composed of heat-resistant fibers. As a heat-resistant fiber, carbon fiber, for example, has a high firing temperature and a high melting temperature, and has sufficient welding spatter adhesion prevention properties. Moreover, the form
It also satisfies the requirements of flexibility and precision. Therefore, if the stainless steel wire of the bowl-shaped partition material 4 in Fig. 1 is replaced with this carbon fiber, it will be extremely effective in improving the efficiency of underwater welding without the need for spatter removal or replacement even when used continuously for a long time. be.

Note that carbon fiber is highly flexible, but in order to give it a spring action similar to that of stainless steel wire, it may be made into a composite material with, for example, epoxy resin. Since the compound purpose is a spring action,
It is not necessarily limited to epoxy resin, but other adhesives may be used. However, commercially available composite materials that use epoxy resin contain a large amount of epoxy resin, so spatter tends to adhere to the resin portion. To eliminate this problem, you can either create a composite material with a reduced amount of epoxy resin, or you can reduce the epoxy content by soaking a conventional composite material in a solvent while it is still uncured. In experiments, spatter adhesion could be prevented by soaking 10 g of composite material in 100 cubic cm of acetone.

2 to 5 wire-shaped pieces of this carbon fiber composite material
A bowl-shaped skirt partition 4 made of brush-like parallel layers with a thickness of mm exhibits a suitable spring constant of 5 to 15 kg/cm.

The inner peripheral layer of the bowl-shaped skirt partition material 4 shown in FIGS. 3 and 4 is composed of the carbon fiber composite wire 12 described above. In this embodiment, an intermediate layer 4b made of a fine mesh of stainless steel wire is placed on the outside of the inner circumferential layer made of brushes of carbon wire 12, and an outer circumferential layer 4c made of brushes of stainless steel wire is superimposed on the outside thereof. A bowl-shaped skirt partition material 4 is used.

If you create a triple structure with an intermediate layer 4b of wire mesh,
The effect of fine-graining the emitted shielding gas increases, and a good shielding effect can be obtained with less gas consumption, but of course, it is possible to obtain a good shielding effect with only a brush layer of carbon wire or stainless steel wire, or even with only a wire mesh layer. Any partition material 4 may be used as long as it is suitable for the target welding part and welding conditions. However, the inner peripheral layer is a fiber aggregate composed of heat-resistant fibers,
It has a spatter adhesion prevention effect. In addition to carbon fiber, ceramic fiber and other high melting point materials can be used as the heat-resistant fiber.

It should be noted that even when carbon fiber, not to mention ceramic, was used as a bowl-shaped partition material for CO ₂ arc welding, which uses carbon dioxide, which is the richest in oxygen, as a shielding gas, no burnout was observed. Carbon fiber is sufficiently stable even in corrosive environments such as seawater.

The fiber aggregate composed of carbon fibers in the inner circumferential layer of the bowl-shaped skirt partition material 4 may be formed into a brush-like parallel layer of wire-like fibers as described above, or may be formed into an air-permeable sheet layer. However, since the latter is inferior to the former in its adaptability to changes in height of the base material surface, it is necessary to consider the usage conditions. When using wire mesh or sheet fiber,
It is advisable to devise ways to adjust to the height of the base material surface by making a narrow cut near the edge of the opening or stacking short strips of narrow width.

Even with the torch 1 attached with such a bowl-shaped skirt partition material 4, if welding is continued while lightly pressing it against the base metal 2, the opening of the bowl-shaped partition material 4 will open, as in the case of the bowl-shaped skirt partition material already described in FIG. As shown in Figures 1 and 3, the edge moves to fit into the recess of the groove 2a, and the shielding gas is applied to the portion of the bowl-shaped partition material 4 near the opening edge where the narrowness is relatively large, as well as the opening edge and the base metal surface. , from the groove surface of the base material, it becomes fine air bubbles and exits into the water. Since the intense arc light is attenuated by the bowl-shaped partition 4, there is no need for protective equipment to protect the eyes and skin of the worker. The welding direction can be changed freely, weaving is possible, and welding in a vertical or upward position is of course also possible. Automatic welding is also easy by attaching this torch 1 to an automatic feed mechanism or self-propelled trolley.

Although a few examples have been explained above,
This idea can be modified in many ways without changing the gist of the idea through the well-known techniques and ingenuity of welding machine designers and welding engineers.For example, the bowl-shaped skirt partition material is not attached directly to the torch tip, It can be attached to the tip of a conventional gas cup to make it easier to replace it with the most suitable one depending on the purpose, or if the bowl-shaped partition material is long, a coil spring can be used to prevent the gap between the fibers from widening locally. It is easy to think of adding a restraining material in the horizontal direction (considering the brush-like fibers as vertical).

Furthermore, the use of the torch of this invention is not limited to the above-mentioned underwater welding and wind-resistant welding, but also for the purpose of light shielding, making it possible to perform welding operations unhindered by arc (plasma) light.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of an embodiment of this invention, Fig. 2 is a sectional view of the tip of a torch with a bowl-shaped partition made only of stainless steel wire, and Fig. 3 is a sectional view of the tip of an embodiment of this invention. 4 is a view seen from the direction perpendicular to the welding groove, and FIG. 4 is a view similarly seen from the direction of welding progress. 1...torch, 2...base material, 4...bowl-shaped skirt partition material.

Claims (1)

[Claims for Utility Model Registration] (1) In a gas-shielded arc or plasma welding torch, attached to the tip of the torch,
It is equipped with a shielding gas supply port that supplies shielding gas with a pressure higher than the water pressure in the welding work area to the welding area so as to surround the electrode, and a bowl-shaped skirt partition that surrounds the high-temperature space of the welding area, and this partitioning material is used during welding. , the opening edge in contact with the base material has flexible elasticity that allows it to adapt and deform to the surface of the base material that changes in height, and has fineness that allows the shielding gas to be released into water through the skirt partition material to form fine bubbles.
A welding torch that uses a bowl-shaped skirt partition material nozzle that enables underwater welding. (2) In a welding torch using the bowl-shaped skirt partition material nozzle described in claim (1), the outer layer of the bowl-shaped partition material is a brush layer of stainless steel wire, and the inner peripheral layer is a spatter-free material. Fiber aggregates made of non-adhesive carbon fibers or similar heat-resistant fibers. (3) In a welding torch using the bowl-shaped skirt partition material nozzle described in claim (1), the bowl-shaped skirt partition material has an outer peripheral layer of a brush layer of stainless steel wire and a fine wire mesh layer. One or both of the inner peripheral layers are carbon fiber brush layers or breathable sheet layers. (4) In a welding torch using the bowl-shaped skirt partition material nozzle described in claim (1), the carbon fiber is a composite material solidified with resin, and the ratio of the resin is determined by the welding spatter. It is suppressed to the extent that it does not adhere.