CN106563870A - Twin-tungsten-electrode electronic swing arc (ESA) argon arc welding - Google Patents

Abstract

The invention provides a double tungsten electrode electronic swing arc argon arc welding equipment, principle and technical proposal. The invention can be applied to manual or automatic welding of the same metal or dissimilar metals, manual or automatic corrosion-resistant alloy surfacing, and can well control the burning loss, dilution, carbon migration, and appearance of the surfacing layer alloy components. and stress deformation of surfacing parts, etc. Principle of action: Before surfacing or welding, the negative electrode of the pulse DC welding machine is connected to the ESA double tungsten argon arc welding torch through the ESA controller, and the positive electrode is connected to the surfacing part or the welding base material; Alternately on and off, and alternately generate gap discharge with the metal base material connected to the positive electrode to form an argon arc. Under the control of the electronic control system, the current of one tungsten electrode is gradually reduced from large to small, and the current of the other tungsten electrode is gradually increased from small to large. When electrified, the arc swings between the two tungsten electrodes during such a repeated process; the principle is shown in Figure 1 of the abstract.

Description

Double tungsten electronic swing arc ( ESA ) argon arc welding

technical field

The present invention relates to the field of metal welding, in particular to a double tungsten electrode electronic swing arc argon arc welding equipment, principle and technical proposal, referred to as: double tungsten electrode ESA argon arc welding.

Background technique

In the field of metal welding, inert gas tungsten argon arc welding (TIG) method is usually required to ensure welding quality, especially in the fields of dissimilar metal welding and corrosion-resistant alloy surfacing, TIG welding has been widely used.

Single tungsten pole TIG welding is to connect one pole of DC or AC welding power supply through one tungsten pole, and the other pole of the power supply is connected to two pre-welded metal base materials, and the gap between the tungsten pole and the base metal is protected by inert gas. The arc is used to melt the welding wire fed into the welding arc to realize metallurgical welding between two base metals; in order to ensure the double-sided forming quality of the weld bead, single tungsten electrode TIG welding is used in the welding process of the same metal or dissimilar metal , it is necessary to continuously swing the tungsten electrode to melt the base metal on both sides of the weld, so that the molten wire and the base metal on both sides of the weld will be metallurgically fused together. The swing mode is "flat swing" when performing manual or automatic TIG welding. and "middle pendulum" two methods, as shown in the instruction manual (attachment 1); when using the "flat pendulum" method for manual argon arc welding, if the operation is not careful, it is easy to make the root unable to penetrate; when using the "middle pendulum" When performing manual argon arc welding, it is necessary to twist the arm continuously, which increases the welding labor intensity; when performing mechanical automatic corrosion-resistant alloy surfacing welding, the "flat pendulum" method is generally used, because the melting point of the base metal is generally higher than The melting point of the corrosion-resistant alloy welding wire is above 100°C. When the surface of the base metal is heated to near the melting point through the corrosion-resistant alloy molten pool, the temperature of the corrosion-resistant alloy layer has exceeded the melting point by about 100°C. Some corrosion-resistant alloys in the alloy The components are burned due to overheating, forming carbides and oxide slag inclusions, which affect the quality of the surfacing layer.

In order to overcome the shortcomings of single tungsten TIG welding, a new single power supply double tungsten argon arc welding technology is currently in the research and development process. The principle of this method is: connect two tungsten pole, the input voltage remains unchanged, the arc voltage and arc current are divided equally by the two tungsten poles to widen the arc width, and the two arcs act on the welding joints of the two pre-welded metal base materials at the same time. When the two tungsten electrodes are melted, they are deposited on both sides of the groove at the same time to realize high-efficiency argon arc welding; The relationship between the tungsten electrode and the base metal determines that when the distance between the tungsten electrode and the base metal is far away, the arc voltage increases and the current decreases; when the distance between the tungsten electrode and the base metal is close, the arc voltage decreases and the current increases. The voltage and arc current can only be the same as those of the tungsten electrode close to the base material, that is, the arc voltage and current cannot be divided equally by the two tungsten electrodes. When a smaller current is required to control the penetration depth or a larger current is required to improve When the welding wire deposition efficiency is low, it cannot really meet the welding needs; when this method is used for manual argon arc welding, the tungsten arc is concentrated at a position closer to the base metal and forms a deflected arc, and the position of the tungsten electrode needs to be adjusted manually. Arc, which is no different from single tungsten electrode welding, is meaningful only when automatic mechanical welding is performed to ensure that the distance between the two tungsten electrodes and the groove of the base metal is equal; if this method is used for surfacing operations, due to the The distance between the tungsten electrode of the surfacing layer and the surfacing welding bead is relatively close, and the distance between the tungsten electrode acting on the base metal and the base metal is relatively long, and the arc will concentrate on the side with the short distance, so mechanical swing arc surfacing is also required In order to overcome this weakness, the surfacing effect is close to that of single tungsten electrode TIG surfacing, which has no practical significance in the surfacing operation, and its weakness.

Double power supply double tungsten electrode TIG surfacing welding is an automatic mechanical surfacing welding method developed on the basis of single tungsten electrode TIG surfacing welding. It is a surfacing welding technology imported from abroad. The argon arc of this method directly heats the surface of the base metal. The welding wire is melted between the two tungsten electrodes and deposited on the surface of the base metal; the dual power supply, double tungsten electrode inert gas shielded surfacing welding does not require mechanical swing, and the width between the double tungsten electrode arcs determines the width of the surfacing welding bead. Cylindrical workpieces are mechanically rotated by the workpiece or rotated in parallel after one revolution. For flat workpieces, the overlap between the weld beads is realized by the mechanical parallel displacement of the workpiece relative to the base material to ensure the continuity of the surfacing layer; the surfacing welding The advantage of the method is to make up for the shortcomings of the single tungsten electrode TIG surfacing method, improve the surfacing welding efficiency, and improve the flatness of the surfacing layer surface; the disadvantage is that the energy of the two tungsten electrode arcs concentrates on a smaller The base metal area increases the heat input in this area and increases the penetration depth of the base metal. When it is used for corrosion-resistant alloy surfacing, it will cause excessive dilution and burning of the corrosion-resistant alloy components. For thinner surfacing welders Parts are likely to cause large physical deformation; two welding power sources are connected to two tungsten poles that are relatively close to each other, which is likely to cause arc interference, and the synchronous control system is easily damaged.

With the development of surfacing and welding technology and the further expansion of application fields, higher requirements are put forward for dimensional restoration, wear-resistant surfacing and corrosion-resistant surfacing, and welding quality, mainly in the following aspects:

1) The penetration depth of the base metal should be reduced as far as possible to control the total amount of the base metal incorporated into the surfacing layer, and reduce the change in the chemical properties of the base metal and the surfacing layer caused by the dilution of the corrosion-resistant alloy composition;

2) Because the degree of change of the microstructure of the weld bead and the base metal depends on the energy of the overlay welding line, and the change of the microstructure of the weld bead or the base metal will affect the chemical and mechanical properties, so the heat input to the base metal should be minimized , in order to prevent the microstructure on the side of the base metal in the fusion zone from greatly changing and affecting the mechanical properties of the base metal;

3) In order to prevent the change of the external physical form of the base metal caused by the welding stress, such as the shrinkage of the steel pipe end due to the stress of the surfacing layer and the bending deformation of the flat plate parts, the thickness of the surfacing layer and the surfacing line should be controlled the amount of energy;

4) For anti-corrosion surfacing welding parts with specific size range requirements, such as surfacing welding inside the welding joint of steel pipes, it must be ensured that the inner diameter range of the surfacing welded pipe end will not exceed the relevant standards due to welding stress shrinkage;

5) In order to ensure the effective thickness of the anti-corrosion surfacing layer and reduce the waste of rare metals, the unevenness of the surfacing layer should be controlled. The plane distance refers to the radial distance between the crests and troughs between two adjacent weld beads in circumferential surfacing).

Contents of the invention

The purpose of the present invention is to provide a double tungsten electronic swing arc electronic swing arc argon arc welding equipment, principle and technical scheme. The present invention can not only be conveniently applied to manual or automatic welding of the same metal or dissimilar Applied to manual or automatic corrosion-resistant alloy surfacing; not only can well control the burning loss, dilution, carbon migration and other factors that affect the internal quality of the surfacing layer, but also can well control the surfacing layer The appearance and stress deformation of surfacing parts are as follows:

(1) Equipment:

1. Electronic swinging arc double tungsten argon arc welding torch:

The head of the welding torch is respectively installed with two tungsten poles which are insulated from each other and parallel with a certain distance. The two tungsten poles are respectively connected to the two output terminals of the electronic arc swing controller. Hot argon hood, referred to as: double tungsten pole ESA argon arc welding torch;

2. Electronic arc swing controller:

The input end of the device is connected to the negative terminal of the pulsed DC welding machine, and the two output ends are respectively connected to the two tungsten electrodes of the ESA welding torch. The voltage of the output terminals is the same and controlled by the pulsed DC welding machine, the current of the two output terminals can be adjusted separately, referred to as: double tungsten pole ESA welding controller;

(2) Principle of action:

Before surfacing or welding operation, the negative electrode of the pulse DC welding machine is connected to the ESA double tungsten argon arc welding torch through the ESA controller, and the positive electrode is connected to the pre-surfacing or welding base material to the positive electrode; The poles are alternately on and off, and alternately generate gap discharge with the metal base material connected to the positive electrode, forming an argon arc. In the repeated process of energizing from small to large, the arc is shown as swinging between the two tungsten electrodes; the principle of the present invention is shown in the description (attached to Figure 2);

(3) Double tungsten electrode ESA welding technical scheme:

When used for welding of the same or dissimilar metals, after the arc is started, the two alternating arcs directly act on the base metal on both sides of the welding joint, and indirectly act on the welding wire fed continuously or intermittently between the two tungsten electrodes to melt the welding wire. And deposited in the welding joint, with the relative movement of the welding torch and the base metal welding joint, the welding process is completed; when applied to welding two metal materials with different wall thicknesses or different melting points, the welding of the two tungsten electrodes can be adjusted separately Current to meet different melting temperature requirements, referred to as: double tungsten ESA welding as shown in the manual (attached to Figure 3);

(4) Double tungsten electrode ESA automatic surfacing technology scheme:

When applied to automatic mechanical surfacing welding, when the surfacing welding of the first pass is performed, the two alternating arcs act on the metal base metal, and indirectly act on the welding wire fed continuously or intermittently between the two tungsten electrodes, so that the welding wire Melting and cladding on the surface of the base metal, with the relative movement of the welding torch and the base metal, the first bead welding is completed. The width of the bead welding bead is determined by the distance between the two tungsten electrodes, and the thickness of the bead It is determined by the relative moving speed and the amount of wire feeding; during the surfacing welding of the second welding pass, the horizontal distance between the welding torch and the first welding pass is automatically moved, and the distance is determined by the surfacing welding process. At this time, a tungsten arc acts on The metal base metal and another tungsten arc act on the edge of the previous welding bead, and the welding wire is continuously fed to melt and deposit the welding wire at the junction of the base metal and the first welding bead. Relatively move to complete the surfacing welding of the second welding pass. Repeat this process to form a continuous surfacing welding layer. The surfacing welding current of the two tungsten electrodes can be adjusted respectively to meet the melting temperature requirements of the base metal and welding material. Abbreviation: ESA surfacing welding such as As shown in the instruction manual (attached to Figure 4);

(5) Anti-corrosion surfacing welding technical scheme for the inner wall of the pipe weld:

When it is applied to the anti-corrosion surfacing welding of the inner wall of the steel pipe weld, after the welding torch is fixed and the steel pipe is rotated to complete the first round of surfacing welding, the welding torch can be automatically shifted to realize the overlap with the previous weld bead, or the spiral can be used. Control the distance of the welding torch to realize the surfacing welding of the continuous surfacing layer; during surfacing welding, one tungsten electrode acts on the base material requiring a larger current, and the other tungsten electrode acts on the surfacing layer requiring a smaller current, which can ensure that the base metal The surface is melted and the corrosion-resistant alloy surfacing layer is not over-melted, referred to as: ESA anti-corrosion surfacing on the inner wall of the pipe weld.

The present invention also has the following features:

1, The content (1) 1. Electronic swinging arc double tungsten argon arc welding torch, referred to as: double tungsten ESA double tungsten argon arc welding torch;

2, The content (1) 2. Double tungsten electrode ESA welding controller;

3. The principle of action in the content (2);

4. The double tungsten electrode ESA welding of the content (3);

5. Double tungsten ESA surfacing welding of the content (4);

6. The content (5) is double tungsten electrode ESA anti-corrosion surfacing on the inner wall of the pipeline weld.

Principle of the present invention is:

1, Controlled by the double tungsten ESA controller, the tungsten arc can swing between the two tungsten electrodes of the double tungsten ESA argon arc welding torch;

2, During the double tungsten ESA welding operation, the two sides of the weld can be heated evenly;

3. During the surfacing operation of corrosion-resistant alloy double tungsten electrode ESA, one tungsten arc directly heats the base metal to ensure that the surface of the base metal reaches the melting temperature; the other tungsten arc heats the previous weld pass to ensure the flatness of the surfacing layer; welding wire Indirect melting between two tungsten arcs prevents burning of the corrosion-resistant components of the wire.

The advantages of the present invention are:

1, Invented a double tungsten electrode ESA argon arc welding method, during the double tungsten electrode ESA welding operation, it can make both sides of the welding joint heated evenly, cancel the manual or mechanical arc swing, and avoid single power source double tungsten electrode argon arc welding The weakness of uneven heating on both sides of the weld;

2, Invented a double tungsten electrode ESA argon arc surfacing method, which maintains the characteristics of smooth surfacing layer and high deposition efficiency of the dual power source and double tungsten electrode surfacing method, and avoids the surfacing layer of the single power source and single tungsten electrode surfacing method The weakness of insufficient flatness and low deposition efficiency; maintains the characteristics of single power supply and single tungsten electrode that can control the thinner surfacing layer, and avoids the weakness that the strip surfacing method and MIG surfacing method cannot control the thinner surfacing layer; In the surfacing operation of corrosion-resistant alloys, the different arc voltages and currents of the two tungsten electrodes are adapted to the different melting points of the welding material and the base metal, which reduces the penetration depth of the base metal and the dilution of the corrosion-resistant alloy components; Compared with the tungsten surfacing method, it reduces power consumption and equipment investment; the smaller surfacing line energy controls the surfacing operation temperature and controls the physical deformation of the base metal caused by the surfacing stress.

Description of drawings

Figure 1 is a schematic diagram of the swing mode of the tungsten electrode during TIG welding with a single tungsten electrode: a, the tungsten electrode swings horizontally, and the arrow points to the swing direction and mode of the tungsten electrode; .

Figure 2 is a schematic diagram of the invention principle of double tungsten pole ESA welding: a, the state where the arc occurs at the left tungsten pole; b, the state where the arc occurs at the right tungsten pole; c, the state where the arc occurs alternately at the left and right tungsten poles.

Figure 3 is a schematic diagram of double tungsten electrode ESA welding: (1) left tungsten electrode; (2) right tungsten electrode; (3), (4) pre-welded metal base metal; (5), (6) tungsten electrode arc action position; (7) Wire feeding position.

Figure 4 is a schematic diagram of double tungsten electrode ESA automatic surfacing welding: (1) the position of the front tungsten electrode and the tungsten electrode and the shape of the argon arc mask; (2) the position of the rear tungsten electrode and the tungsten electrode and the shape of the argon arc mask; (3) ) arc metal base metal; (4) surfacing layer formed by continuous welding passes; (5) wire feeding direction and position; (6) welding torch travel distance direction; (7) relative movement direction of welding torch and base metal.

The above is only the equipment, device and principle of the present invention and the specific technical solutions applied to welding and surfacing, but the scope of protection of the present invention is not limited thereto, and any person familiar with the technical field shall be informed by the disclosure of the present invention Within the technical scope, changes or substitutions can be easily thought of, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (7)

1. it is an object of the invention to provide a kind of couple of tungsten electrode electronics swinging arc Electronic swing Arc argon arc welding equipments, principle and technical scheme, referred to as：Double tungsten electrode ESA argon arc weldings；The present invention can not only be conveniently applied to the manually or automatically welding of same metal or dissimilar metal, can also be conveniently applied to manually or automatically corrosion resistant alloy built-up welding；Not only can be very good scaling loss, dilution, carbon diffusion of control weld overlay alloy composition etc. affects the factor of overlay cladding inherent quality, can also well control the stress deformation of overlay cladding mode of appearance and heap weldment, and its particular content is as follows：

（One）, equipment：

1）Electronics swinging arc electrode TIG rifle：Arc welding gun head portion is respectively mounted mutually insulated, parallel, and with certain distance two tungsten electrodes, two tungsten electrodes connect respectively two lead-out terminals of electronics swinging arc controller, equipped with the heat-resisting argon gas cover with tungsten electrode insulation outside two tungsten electrodes, referred to as：Double tungsten electrode ESA argon-arc welding guns；

2）Electronics swinging arc controller：The input connection pulse direct current welding machine negative terminal of the device, two output ends connect respectively two tungsten electrodes of ESA welding guns, the effect of the controller is that the cathodal current for making pulse direct current welding machine replaces two lead-out terminals of UNICOM, the voltage of two lead-out terminals is identical and is controlled by pulse direct current welding machine, the electric current difference of two lead-out terminals is adjustable, referred to as：Double tungsten electrode ESA welding controllers；

（Two）, action principle：

Before built-up welding or weld job, pulse direct current welding machine negative pole connects ESA double-tungsten argon arc welding guns by ESA controllers, and positive pole connects pre- built-up welding or welding base metal connects positive pole；When welding or built-up welding operation, cathodal current replaces switching between two tungsten electrodes and replaces and the base material metal generation gap discharge for being connected positive pole, form argon gas electric arc, due to the control of electronic control system, a tungsten electrode electric current from greatly gradually little power-off, another tungsten electrode electric current then from it is little gradually it is big be powered so repeatedly during, show as electric arc and swing between two tungsten electrodes；

（Three）, double tungsten electrode ESA solder technology schemes：When for of the same race or different-metal material welding, the starting the arc latter two replace electric arc directly act on weld bond both sides base material metal respectively, the welding wire that indirectly-acting is continuously or intermittently sent between two tungsten electrodes, make wire melting and be deposited in weld bond, with the relative movement of welding gun and mother metal weld bond, welding process is completed；When two different walls of welding or different melting points metal materials are applied to, the welding current that can respectively adjust two tungsten electrodes is required with adapting to different fusion temperatures, referred to as：Double tungsten electrode ESA welding；

（Four）, double tungsten electrode ESA automatic surfacing technical schemes：When being applied to automation built-up welding, when the built-up welding of first welding bead is carried out, two alternating electric arcs all act on base material metal, the welding wire that indirectly-acting is continuously or intermittently sent between two tungsten electrodes, make wire melting and deposition is in base material metal surface, with the relative movement of welding gun and mother metal, complete the built-up welding of the first welding bead, the width of bead welding is determined that the thickness of welding bead is determined by relative moving speed and silk feeding quantity by the distance between two tungsten electrodes；When the second welding bead built-up welding is carried out, automatically move the horizontal range of welding gun and the first welding bead, the size of distance is determined by bead-welding technology, now, one tungsten electrode arc acts on base material metal, another tungsten electrode arc acts on the edge of previous bead welding, it is continuously introduced into welding wire, make wire melting and be deposited over the intersection of mother metal and the first welding bead, with the relative movement of welding gun and mother metal, complete the built-up welding of the second welding bead, so repeatedly, form continuous overlay cladding, the welding current that two tungsten electrodes can respectively be adjusted adapts to respectively the fusion temperature requirement of mother metal and wlding, referred to as：Double tungsten electrode ESA built-up welding；

（Five）, pipe welding port inner wall anti-corrosive technique for overlaying scheme：When steel pipe weld bond inner wall anti-corrosive built-up welding is applied to, fix in welding gun, steel pipe rotary completes the heap postwelding of first week, moved automatically away from the overlap joint realized and between previous welding bead by welding gun, it is also possible to welding gun is controlled by spiral and is moved away from realizing the built-up welding of continuous overlay cladding；During built-up welding, a tungsten electrode acts on the mother metal for requiring larger current, and another tungsten electrode acts on the overlay cladding for requiring smaller current, it is ensured that mother metal surface melting and corrosion resistant alloy overlay cladding is not superfused, referred to as：The double tungsten electrode ESA anti-corrosion built-up welding of pipe welding port inwall.

2. the content according to claim（One）In 1, electronics swinging arc electrode TIG rifle, referred to as：ESA double-tungsten argon arc welding guns.

3. the content according to claim（One）In 2）Double tungsten electrode ESA welding controllers.

4. content described in the content according to claim（Two）Described in action principle.

5. content described in the content according to claim（Three）In double tungsten electrode ESA welding.

6. content described in the content according to claim（Four）In double tungsten electrode ESA built-up welding.

7. content described in the content according to claim（Five）In the double tungsten electrode ESA anti-corrosion built-up welding of pipe welding port inwall.