JPH0741588Y2 - Butt welding equipment for piping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a welding device used for butt welding welding of pipes.

[Prior Art] When welding a butt-welding joint of a pipe made of a metal having a high melting point, for example, titanium, conventionally, as shown in FIGS. 3 and 4, the pipes 1a and 1b as base materials are conventionally used. The TIG welding torch 3 is set to face the butt-welding joint 2 of No. 3, and an inert gas such as argon is blown out as the shield gas G through the gas nozzle 3a, and the tungsten electrode 3b and the portion to be welded in an inert gas atmosphere. An arc is generated between the two and the heat of the butt welding joint 2 is welded over the entire circumference.

[Problems to be Solved by the Invention] However, in the conventional welding method, the butt welding joint 2 is welded in the circumferential direction while the shielding gas G is sprayed only around the tip of the TIG welding torch 3. Therefore, it takes time to suppress the heat input to the vicinity of the welded portion, and the heat input to the welding may oxidize the metal.
Since the butt welding joint 2 is welded at a low speed,
Since the heating time is long and the melting point is high, the position near the welded portion may be damaged.

Therefore, the present invention is intended to prevent the weld metal from being oxidized by the heat input to the weld and to efficiently cool the weld by suppressing the heat input to the vicinity of the weld.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a ring-shaped shield on one side in a donut-shaped shield case that can be fitted to pipes to be joined. A gas injection pipe having a large number of gas injection holes along the circumference is installed so that the gas injection holes face forward, and at the front position of the gas injection pipe,
A punching metal, a fluid resistor that creates a turbulent flow in the gas to equalize the gas concentration, and an injection focusing plate that has multiple holes in the radial direction that inject the gas diagonally inward and have a large number around the entire circumference. A shield gas ejecting device that is installed in order and allows the shield gas ejected from the gas ejecting pipe to be ejected uniformly from the front surface of the shield case by sequentially passing through the holes of the punching metal, the fluid resistor, and the injection focusing plate. The shield gas jetting device is fitted to both pipes to be joined so as to face each other with a butt-welding joint portion of the two pipes sandwiched therebetween, and is jetted out from the hole of the jet focusing plate on the front face. A state in which shield gas is jetted from the shield gas jetting device to the entire surface of the butt weld joint so that the gas is focused on the butt weld joint. The projecting alignment weld joint and configuration so as to weld in TIG welding torch.

[Operation] When an inert gas such as argon is ejected as a shield gas from the gas injection pipe in the shield case, the inert gas passes through the punching metal and the fluid resistor to have a uniform concentration over the entire circumference, and the front surface is ejected. Since it is uniformly ejected from the holes of the focusing plate, the inert gas is uniformly blown over the entire circumference of the butt-welding joint of the pipe, and the butt-welding joint is gas-shielded. When welding is performed with the TIG welding torch in this state, the vicinity of the weld becomes an inert gas atmosphere, heat input to the vicinity of the weld can be suppressed small, and oxidation of the deposited metal can be prevented. Further, since the butt-welded joint is cooled by gas over the entire circumference, cooling efficiency is improved.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention, which is formed into a donut shape by forming a hole in the center so that it can be fitted to the outside of the pipes 1a and 1b as the base materials to be joined. Inside the shield case 5, a porous gas injection pipe 6 formed in a ring shape and provided with a large number of gas injection holes 7 on the entire circumference on one side.
Is installed so that the gas injection hole 7 faces forward, and at a position in front of the porous gas injection pipe 6 in the shield case 5,
Punching metal 8 and a fluid resistor 9 such as a wire mesh for generating a turbulent flow in a gas to equalize the gas concentration
Then, the injection focusing plate 10 having the holes 10a for injecting the gas obliquely inward so as to focus the gas on the butt-welding joint 2 of the pipes 1a and 1b is installed in order from the rear to the front, and the porous gas injection is performed. A shield gas jetting device in which the gas G jetted from the pipe 6 is jetted forward from the jet focusing plate 10 after being made turbulent by the fluid resistor 9 through the punching metal 8 to equalize the gas concentration. 4 sets 2 sets. An inert gas supply pipe 13 having a pressure gauge 11 and a flow rate adjusting valve 12 is connected to the porous gas injection pipes 6 of each of the shield gas ejection devices 4 to connect the pipes 1a and 1b by butt welding. The inert gas supply pipe 13 is connected to the inert gas supply pipe 14 for supplying the inert gas to the TIG welding torch 3 for welding 2. Reference numeral 15 is a guide and support ring attached to the rear end of the shield case 5, 16 is a pressure gauge, 17 is a flow rate adjusting valve, and 18 is a welding rod.

When welding the butt-welding joint 2 of the pipes 1a and 1b, the shield gas injection device 4 is inserted along the pipes 1a and 1b at the joint-side ends of the pipes 1a and 1b, and the shields are inserted. The front side of the gas ejection device 4, that is, the injection converging plates 10 are opposed to each other and set on the pipes 1a and 1b, and then the gas ejected from the front surface of the shield gas ejection device 4 is applied to the butt welding joint portion 2. The facing dimension L of both shield ejection devices 4 is adjusted so as to be sprayed.

When the shield gas ejection device 4 is placed at a predetermined position as described above, the TIG welding torch 3 is set to face the butt welding joint portion 2 and the flow rate adjusting valve 17 of the inert gas supply pipe 14 is adjusted appropriately. And gas nozzle for TIG welding torch 3
An inert gas is supplied as a shield gas G into the inside of 3a, and is ejected from the gas nozzle 3a toward the tip of the TIG welding torch 3 so as to surround the tungsten electrode 3b. At this time, the shields which are opposed to each other on the pipes 1a and 1b are shielded. The flow control valve 12 is appropriately adjusted to the porous gas injection pipe 6 of the gas injection device 4 to supply an inert gas as the shield gas G, and the inert gas is ejected from the front surface of each shield gas ejection device 4 so that the butt welding joint 2 Focus the shielding gas on the front side. The amount of inert gas ejected from the TIG welding torch 3,
The amount of gas jetted from each of the shield gas jetting devices 4 is adjusted by the flow rate adjusting valves 17 and 12. The inert gas jetted from the front surface of the shield gas jetting device 4 is diffused while the gas jetted from the hole 7 of the porous gas jet pipe 6 passes through the punching metal 8 and the fluid resistor 9 to pass through the gas. Since the concentration is equalized, it is possible to uniformly cover the entire circumference of the butt welding joint portion 2.

When the butt welding joint portion 2 is welded by the TIG welding torch 3 in such a state, the welded portion is also covered with the shield gas G ejected from the shield gas ejecting device 4, so that the weld metal portion is welded. Becomes an inert gas atmosphere and the butt-welded joint 2 is efficiently cooled, so that heat input to the vicinity of the weld can be suppressed to be small and oxidation of the deposited metal can be prevented. Even in the case of high melting point welding, the vicinity of the welded portion is not damaged.

[Advantages of the Invention] As described above, according to the welding device of the present invention, the shield case is formed in a donut shape so that it can be fitted into the pipes to be joined, and the shield case is formed in a ring shape over the entire circumference on one side. A gas injection pipe having a large number of gas injection holes is installed such that the gas injection holes face forward, and a punching metal and a turbulent flow are generated in the gas at the front position of the gas injection pipe to make the gas concentration uniform. The flow resistance element and the injection focusing plate having a large number of holes for injecting gas obliquely inward in the radial direction and having a large number around the entire circumference are installed in order, and the shield gas injected from the gas injection pipe is punched. , A fluid resistor, and a shield gas ejecting device which is configured to be capable of ejecting uniformly from the front surface of the shield case by sequentially passing through the holes of the fluid concentrator and the jet focusing plate. Set on the pipes so that they face each other with the butt-welding joint sandwiched between them, and with the TIG welding torch in a state in which the shield gas is ejected by the shield gas ejection device to the entire circumference of the butt-welding joint to form a barrier. Since the welding is performed, the inert gas ejected from the front surface of the shield gas ejector has a resistance to the gas ejected from the holes of the gas injection pipe having a large number of gas injection holes through the punching metal and the fluid resistance. Since it is diffused while passing through the body and the gas concentration is equalized, it must be sprayed from the many holes of the front focusing plate to the butt weld joint of the pipes to be joined over the entire circumference. As a result, the entire circumference of the butt-welded joint can be uniformly covered, and the molten metal is covered with an inert gas atmosphere during welding, so that the contact with the atmosphere is maximized. The heat input to the vicinity of the weld can be suppressed to a minimum and the metal oxidation due to the heat input of the weld can be prevented.At the time of welding, the entire surface of the butt weld joint is shielded. Since the gas is blown, the welded part can be cooled efficiently, and further, the welded part can be kept covered with a uniform inert gas atmosphere even after the welding.
It is possible to achieve excellent effects such as cooling the welded joints uniformly and efficiently.

[Brief description of drawings]

FIG. 1 is a partially cut front view showing an example of butt welding contact of pipes of the present invention, FIG. 2 is a view taken along the line II-II in FIG. 1, and FIG.
FIG. 4 is a schematic front view of the conventional method, and FIG. 4 is a view on arrow IV of FIG. 1a, 1b …… Piping, 2 …… Butt weld joint, 3 …… TIG welding torch, 4 …… Shield gas injection device, 5 ……
Shield case, 6 ... Porous gas injection tube, 7 ... Hole, 8
…… Punching metal, 9 …… Fluid resistor, 10 …… Jet focusing plate.

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. A gas injection tube, which is formed in a ring shape and has a large number of gas injection holes on one side over the entire circumference, in a doughnut-shaped shield case that can be fitted to pipes to be joined. Install it so that it faces forward,
At the front position of the gas injection pipe, a punching metal, a fluid resistor for generating a turbulent flow in the gas to equalize the gas concentration, and a hole for injecting the gas obliquely inward are formed in multiple stages in the radial direction. A large number of injection focusing plates are installed in sequence over the entire circumference, and the shield gas injected from the gas injection pipe is sequentially ejected from the front surface of the shield case by sequentially passing through holes in the punching metal, the fluid resistor, and the injection focusing plate. A shield gas jetting device configured as described above is configured so that the shield gas jetting device is fitted to both pipes to be joined so as to face each other with a butt-welding joint portion of the both pipes sandwiched therebetween, and the front face is jetted. The facing distance is set so that the shield gas ejected from the hole of the focusing plate is converged to the butt welding joint, and the shield gas is ejected from the shield gas ejecting device over the entire surface of the butt welding joint. Butt welding apparatus of the pipe, characterized by comprising a projecting alignment weld joint to be welded with TIG welding torch in a state of being ejected Rudogasu.