CN104668743B - A kind of device utilizing TIG weld method to realize PLASMA ARC WELDING - Google Patents

Abstract

The invention relates to a device for realizing plasma arc welding by using a TIG welding method, which comprises an upper torch body and a lower torch body. The upper nozzle is connected to the lower end of the upper gun body, and the coaxial connection between the upper nozzle and the lower gun body is realized by adopting a mechanical connection method. A water-cooling tank, an upper water inlet pipe, an upper water outlet pipe, and an upper air intake pipe are opened in the wall of the upper gun body, and a flow guide, a tungsten pole clip and a tungsten pole are coaxially arranged in the upper gun body, and the tungsten pole passes through the tungsten pole Clip and extend into the lower gun body. A water cooling tank, a lower water inlet pipe, a lower water outlet pipe and a lower air intake pipe are opened in the wall of the lower gun body, and a lower nozzle is connected to the inner wall of the lower end of the lower gun body, and a hole is opened in the center of the lower nozzle, and the tungsten electrode There is a certain distance between the end of the nozzle and the central channel of the lower nozzle, and the outer wall of the lower end of the lower gun body is connected with a protective cover. The invention can realize plasma arc welding, can significantly improve the efficiency of TIG welding and the quality of welding seam, and the welding cost is lower than that of traditional plasma arc welding.

Description

A device for plasma arc welding using TIG welding method

technical field

The invention relates to a device for realizing plasma arc welding by using a TIG welding method.

Background technique

Tungsten argon arc welding (TIG) has the advantages of low welding cost, stable welding process, beautiful weld shape and good protection effect. It has been widely used in production, especially for high-quality non-ferrous metals, stainless steel and titanium alloys. Welding is the most advantageous. However, due to the limited current-carrying capacity of the tungsten electrode, the arc power is restricted, resulting in a shallow molten pool and low welding efficiency. The compression arc welding process born on the basis of TIG welding - plasma arc welding technology (PAW) can significantly improve the low production efficiency of TIG welding. The tungsten electrode of the plasma arc welding torch is retracted into the nozzle, and the aperture of the nozzle is relatively small. When the arc passes through the nozzle hole, the cross-sectional area of the arc column is limited, the arc cannot expand freely, and an external restraint effect is generated to form a plasma arc with high current density. High-current plasma arc welding (100-300A) can completely penetrate the workpiece and realize plasma arc welding, that is, under the action of the plasma arc, a small hole is formed through the molten pool to realize single-sided welding and double-sided forming.

Compared with traditional TIG welding, due to its special pinhole effect, plasma arc welding has the advantages of large weld depth-to-width ratio, narrow heat-affected zone, good forming quality, and high welding productivity. It can be widely used in welding of various metal materials , surfacing, spraying, cutting, etc. However, because the equipment cost of the plasma welding machine is much higher than that of the TIG welding machine with the same electric power, the one-time investment of the equipment is large; because the structure of the traditional plasma welding torch is complex and heavy, it is not conducive to manual operation. The above two reasons limit the industrial application of plasma arc welding technology.

To sum up, the existing TIG welding technology has low welding efficiency, while the traditional plasma arc welding technology improves the welding productivity, but the welding cost is high, and the welding device is relatively heavy. If the existing TIG welding torch can be modified to realize plasma Arc welding can not only improve the welding efficiency of TIG welding, but also significantly reduce the production cost of plasma arc welding method, and can also enhance the flexibility of plasma arc welding, so it has great application value.

Contents of the invention

Based on the above deficiencies, the purpose of the present invention is to provide a device that utilizes the TIG welding method to realize plasma arc welding, in order to realize low-cost plasma arc welding technology, which can be performed by manual or automatic welding. Significantly lower compared to plasma arc welding.

The technology adopted in the present invention is as follows: a device for realizing plasma arc welding by using TIG welding method, including electrode cap (1), sealing ring (2), upper gun body (3), tungsten pole clip (4), diversion piece (6), upper nozzle (7), centering ring (8), lower gun body (9), lower outlet pipe (10), protective cover (11), lower nozzle (12), tungsten pole (13), lower Air inlet pipe (14), lower water inlet pipe (15), upper air inlet pipe (21), upper water inlet pipe (22) and upper water outlet pipe (23); thread pair connection is adopted between electrode cap (1) and upper gun body (3) , the sealing ring (2) is located between the electrode cap (1) and the upper gun body (3), the upper gun body (3) has a water cooling groove (5) in the wall, and the center of the electrode cap (1) has two The tunnel, the upper air inlet pipe (21), the upper water inlet pipe (22) and the upper water outlet pipe (23) are connected on the side wall of the upper gun body (3), and the upper gun body (3) is equipped with tungsten electrode clips (4) and flow guides (6) and tungsten pole (13), tungsten pole clamp (4), flow guide (6) and tungsten pole (13) are coaxially arranged with the upper gun body (3), and the tungsten pole clamp (4) passes through the electrode cap The short channel of (1) extends into the inner hole of the deflector (6) along the axis of the upper gun body (3), and the tungsten pole (13) passes through the long channel of the electrode cap (1) and the tungsten electrode along the axis of the upper gun body (3). Pole clamp (4), the lower end of the upper gun body (3) is threadedly connected with the upper end of the upper nozzle (7), the lower end of the upper nozzle (7) is coaxially fastened with the upper end of the lower gun body (9), and the lower end of the lower gun body (9) Connect with the upper end of the lower nozzle (12) through the inner wall thread, the center of the bottom end of the lower nozzle (12) has an air flow restriction hole, and the lower end of the lower gun body (9) is connected with the protective cover (11) through the outer wall thread; the lower gun body (9) ) inner wall is provided with a water-cooling groove, the side wall of the lower gun body (9) is connected with the lower water outlet pipe (10), the lower air inlet pipe (14) and the lower water inlet pipe (15), and the centering ring (8) is fixed on the lower gun body (9 ) at the stepped structure of the inner wall along the axial direction, the tungsten pole (13) extending into the lower gun body (9) passes through the centering ring (8).

The present invention also has the following technical features:

1. Two channels as mentioned above, one is the same as the outer diameter of the tungsten pole (13), and the other is the same as the outer diameter of the tungsten pole clamp (4).

2. As mentioned above, the inner wall of the upper gun body (3) and the outer wall of the flow guide (6) have a stepped structure along the axial direction, and the flow guide (6) is fixed on the upper gun body (3) through the stepped structure. ); the inner wall of the flow guide (6) is an inclined step structure, the inner diameter of the flow guide (6) gradually decreases at the inclined step, and the inner diameter of the narrowest part is 1-1.5mm larger than the diameter of the tungsten pole (13).

3. The lower end of the upper nozzle (7) is tightly connected with the upper end of the lower gun body (9) through threads.

4. The outer sides of the upper gun body (3) and the lower gun body (9) as mentioned above are respectively covered with clamps (16); the two clamps (16) are fastened and connected by bolts.

5. The welding power supply system of this device is composed of two power sources, one power source is connected between the tungsten electrode (13) and the lower nozzle (12), and is the arc starting power source; the other power source is connected between the tungsten electrode (13) and the workpiece between the main power supply; high-frequency arcing is used to generate a small arc between the tungsten electrode (13) and the inner wall of the lower nozzle (12). A charged high-temperature gas layer is gradually generated. Under the high no-load voltage of the main power supply, the arc is automatically transferred to burn between the electrode and the workpiece. When the arc passes through the channel of the lower nozzle (12), it is restrained due to the arc compression effect, the energy density of the arc increases, and the temperature increases, thereby realizing plasma arc welding.

6. Adjust the tungsten electrode (13) so that the length protruding from the upper nozzle (7) is 5-10 mm, and adopt appropriate welding process parameters to realize traditional TIG welding.

Features and beneficial effects of the present invention:

(1) The traditional TIG welding torch has been properly modified, and TIG welding equipment can be used to realize plasma arc welding, which improves the welding efficiency and weld quality of TIG welding;

(2) Compared with traditional plasma arc welding, the device for plasma arc welding using TIG welding method can significantly reduce the welding cost;

(3) TIG welding can be realized when only the upper gun body structure is used for welding, and the plasma arc welding can be realized after the upper gun body and the lower gun body are assembled coaxially, which expands the application range of traditional TIG welding tools;

(4) The plasma arc welding can be realized manually, or the device can be assembled into an automatic welding system to realize automatic plasma arc welding, which is flexible and convenient.

Description of drawings

Fig. 1 is a structural diagram of a welding gun according to Embodiment 1 of the present invention.

Figure 2 is the first schematic diagram of the welding power supply circuit.

Fig. 3 is a structure diagram of a welding gun according to Embodiment 2 of the present invention.

detailed description

Below according to the accompanying drawing of the description, give an example to further illustrate:

Example 1

As shown in Figure 1, a device using TIG welding method to realize plasma arc welding, including electrode cap 1, sealing ring 2, upper gun body 3, tungsten pole clamp 4, flow guide 6, upper nozzle 7, and centering ring 8 , the lower gun body 9, the lower water outlet pipe 10, the protective cover 11, the lower nozzle 12, the tungsten pole 13, the lower air inlet pipe 14, the lower water inlet pipe 15, the upper air inlet pipe 21, the upper water inlet pipe 22 and the upper water outlet pipe 23; the electrode cap 1 and The upper gun body 3 is connected by a pair of threads, the sealing ring 2 is located between the electrode cap 1 and the upper gun body 3, a water cooling groove 5 is opened in the wall of the upper gun body 3, and the center of the electrode cap 1 is respectively opened with a tungsten electrode 13 The channel with the same outer diameter and the same channel as the outer diameter of the tungsten pole clip 4; the upper air inlet pipe 21, the upper water inlet pipe 22 and the upper water outlet pipe 23 are connected to the side wall of the upper gun body 3, and the upper gun body 3 is equipped with a tungsten pole clip 4, The deflector 6 and the tungsten pole 13, the tungsten clamp 4, the deflector 6 and the tungsten pole 13 are coaxially arranged with the upper gun body 3, and the inner wall of the upper gun body 3 and the outer wall of the deflector 6 are located along the axial direction. Stepped structure, the flow guide 6 is fixed in the upper gun body 3 through a stepped structure, the tungsten electrode clip 4 passes through the short channel of the electrode cap 1 and extends into the inner hole of the flow guide 6 along the axis of the upper gun body 3, and the tungsten electrode 13 Pass through the long hole of the electrode cap 1 and the tungsten pole holder 4 along the axis of the upper gun body 3, the inner wall of the flow guide 6 is an inclined step structure, the inner diameter of the flow guide 6 gradually decreases at the inclined step, and the inner diameter of the narrowest part is smaller than that of the tungsten electrode 13 The diameter is 1-1.5 mm larger; when the electrode cap 1 and the upper gun body 3 are screwed together, the upper end of the tungsten electrode clamp 4 is under downward pressure, and the lower end is in contact with the inclined stepped structure of the flow guide 6, tungsten The lower end of the pole clamp 4 shrinks gradually to realize the clamping of the tungsten electrode 13; the lower end of the upper gun body 3 is threadedly connected with the upper end of the upper nozzle 7, the lower end of the upper nozzle 7 is connected with the upper end of the lower gun body 9 through threads, and the lower end of the upper nozzle 7 Coaxial with the lower gun body 9, the lower end of the lower gun body 9 is connected with the upper end of the lower nozzle 12 through the inner wall thread, and the lower end of the lower gun body 9 is connected with the protective cover 11 through the outer wall thread; the inner wall of the lower gun body 9 has a water cooling groove, and the lower gun body The 9 side walls are connected with the lower water outlet pipe 10, the lower air inlet pipe 14 and the lower water inlet pipe 15, and the centering ring 8 is fixed on the stepped structure of the inner wall of the lower gun body 9 along the axial direction, and the tungsten pole 13 inserted into the lower gun body 9 passes through Pass to Central 8.

When using the device of this invention to realize plasma arc welding, the effect of the shielding gas fed into the upper air intake pipe 21 is equivalent to that of the ion gas in plasma arc welding, and the effect of the shielded gas fed into the lower air intake pipe 14 is equivalent to that in plasma arc welding. protective gas. As shown in Figure 2, the welding power supply system consists of two power sources, one power source is connected between the tungsten electrode 13 and the lower nozzle 12, which is the arc starting power source; the other power source is connected between the tungsten electrode 13 and the workpiece, and is the main power source . A small arc is generated between the tungsten electrode 13 and the inner wall of the lower nozzle 12 by high-frequency arc starting. After arcing, as the electrode is heated, the space temperature rises, and a charged high-temperature gas layer is gradually generated between the electrode and the workpiece. Under the high no-load voltage of the main power supply, the arc automatically transfers to burn between the electrode and the workpiece. When the arc passes through the channel of the lower nozzle 12, it is restrained due to the arc compression effect, the energy density of the arc increases, and the temperature increases, thereby realizing plasma arc welding. After the lower gun body 12 is removed from the overall structure, adjust the tungsten electrode 13 so that the length protruding from the upper nozzle 7 is 5-10 mm, and adopt appropriate welding process parameters to realize traditional TIG welding.

Example 2

As shown in Figure 3, the structure of this welding torch is the same as in Embodiment 1, the difference is that the upper nozzle 7 and the outer wall of the lower torch body 9 are each covered with a clip 16, through screw holes 17, bolts 18, spring washers 19 and Nut 20 realizes clamping and connection of upper nozzle 7 and lower gun body 9 .

Claims (6)

1. A device for plasma arc welding by TIG welding method, comprising electrode cap (1), sealing ring (2), upper gun body (3), tungsten pole clip (4), flow guide (6), upper Nozzle (7), centering ring (8), lower gun body (9), lower outlet pipe (10), protective cover (11), lower nozzle (12), tungsten pole (13), lower air intake pipe (14), The lower water inlet pipe (15), the upper air inlet pipe (21), the upper water inlet pipe (22) and the upper water outlet pipe (23); it is characterized in that the electrode cap (1) and the upper gun body (3) are connected by thread pairs, and the airtight The ring (2) is located between the electrode cap (1) and the upper gun body (3), the upper gun body (3) has a water cooling groove (5) in the wall, and the center of the electrode cap (1) has two holes respectively, Upper air inlet pipe (21), upper water inlet pipe (22) and upper water outlet pipe (23) are connected on the side wall of upper gun body (3), and tungsten pole clip (4) and guide piece (6) are housed in upper gun body (3). ) and the tungsten pole (13), the tungsten pole clip (4), the deflector (6) and the tungsten pole (13) are coaxially arranged with the upper gun body (3), and the tungsten pole clamp (4) passes through the electrode cap (1 ) along the axis of the upper gun body (3) extends into the inner hole of the flow guide (6), and the tungsten pole (13) passes through the long channel of the electrode cap (1) and the tungsten pole clamp along the axis of the upper gun body (3) (4), the lower end of the upper gun body (3) is threadedly connected with the upper end of the upper nozzle (7), the lower end of the upper nozzle (7) is coaxially fastened with the upper end of the lower gun body (9), and the lower end of the lower gun body (9) passes through the inner wall The thread is connected with the upper end of the lower nozzle (12), and the center of the bottom end of the lower nozzle (12) is provided with an air flow restricting hole, and the lower end of the lower gun body (9) is connected with the protective cover (11) through the thread on the outer wall; the inner wall of the lower gun body (9) There is a water cooling groove, and the side wall of the lower gun body (9) is connected with the lower water outlet pipe (10), the lower air inlet pipe (14) and the lower water inlet pipe (15), and the centering ring (8) is fixed on the inner wall of the lower gun body (9) At the stepped structure along the axial direction, the tungsten pole (13) extending into the lower gun body (9) passes through the centering ring (8). 2. A kind of device utilizing TIG welding method to realize plasma arc welding according to claim 1, characterized in that: of the two channels, one has the same outer diameter as the tungsten pole (13), and the other has the same outer diameter as the tungsten pole clamp (13). 4) The outer diameter is the same. 3. A device for realizing plasma arc welding by TIG welding method according to claim 1, characterized in that: the inner wall of the upper gun body (3) and the outer wall of the flow guide (6) are separated along the axial direction. There is a stepped structure, and the flow guide (6) is fixed in the upper gun body (3) through the stepped structure; the inner wall of the flow guide (6) is an inclined step structure, and the inner diameter of the flow guide (6) gradually decreases at the inclined step. Small, the inner diameter at the narrowest point is 1-1.5 mm larger than the diameter of the tungsten pole (13). 4. A device for realizing plasma arc welding by TIG welding method according to claim 1, characterized in that: the lower end of the upper nozzle (7) and the upper end of the lower gun body (9) are fastened by threads. 5. A kind of device utilizing TIG welding method to realize plasma arc welding according to claim 1, characterized in that: the outer sides of the upper gun body (3) and the lower gun body (9) are respectively covered with clamps ( 16); the two clamps (16) are fastened and connected by bolts. 6. A kind of device utilizing TIG welding method to realize plasma arc welding according to any one of claims 1-5, it is characterized in that: the welding power supply system of this device is made of two-way power supply, and one-way power supply is connected to tungsten pole ( 13) and the lower nozzle (12) is an arc starting power supply; the other power supply is connected between the tungsten pole (13) and the workpiece as the main power supply; high-frequency arc starting is used to make the tungsten pole (13) and the lower nozzle ( 12) A small arc is generated between the inner walls. After the arc is started, as the electrode is heated, the space temperature rises, and a charged high-temperature gas layer is gradually generated between the electrode and the workpiece. Under the high no-load voltage of the main power supply, the arc is automatically transferred to burn between the electrode and the workpiece When the arc passes through the channel of the lower nozzle (12), it is restrained due to the arc compression effect, the arc energy density increases, and the temperature increases, thereby realizing plasma arc welding.