CN107322143B

CN107322143B - Long-distance digital gas-shielded double-wire welding robot

Info

Publication number: CN107322143B
Application number: CN201710762120.9A
Authority: CN
Inventors: 张毅
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-08-30
Filing date: 2017-08-30
Publication date: 2023-03-17
Anticipated expiration: 2037-08-30
Also published as: CN107322143A

Abstract

The invention relates to a long-distance digital gas-shielded double-wire welding robot, which structurally comprises an operation vehicle, a welding trolley and a cable, wherein the operation vehicle is connected with the welding trolley; the operation vehicle is used for integral control and provides materials and electric power required by welding for the welding trolley, the welding trolley is used for controlling the stable movement and swing of a welding gun in the welding process, and the operation vehicle is connected with the welding trolley through a cable; the cable is composed of welding pipes of two wire feeders on the operation vehicle, and the tail end of the cable is connected with a double-wire welding gun on the welding trolley. The advantages are that: 1) The mixed protective gas is adopted, so that the service life of a welding gun is prolonged, the welding quality is improved, and splashing is reduced; 2) The program control and digital program control are adopted, so that the efficiency is improved, the manual labor is reduced, and the cost is reduced; 3) By adopting the double-wire welding technology, the method is efficient and quick, reduces the material consumption, can save 25% of electric power and improves the welding quality.

Description

Long-distance digital gas-shielded double-wire welding robot

Technical Field

The invention relates to a long-distance digital gas melting and gas protecting double-wire welding robot, and belongs to the technical field of robot welding.

Background

In the prior art, the traditional monofilament welding such as gas shield welding and submerged arc welding has singleness, a large amount of manpower and material resources are consumed during operation, the work efficiency is difficult to improve, and the requirements of modern industrial production on high speed, high efficiency and low energy consumption of the welding technology cannot be met; therefore, the development of the twin wire bonding technology has been one of the hot spots and difficulties in the field of the bonding technology.

For welding medium and long thick plates, a double-wire welding technology is generally adopted to improve the welding efficiency and quality, the double-wire welding current is smaller, so that larger penetration is favorably formed, two welding wires are mutually heated, the energy of electric arcs is fully utilized, larger penetration rate is realized, sufficient molten metal and base metal in a molten pool are fully fused, and the welding wires are attractive in forming; however, the structure of large medium and long thick plates is no longer suitable for manual operation, and how to solve the problems of large energy consumption, low welding efficiency and the like caused by long-distance (generally 10 to 20m) welding in the fields such as ship manufacturing, pipeline butt joint, vehicle forming and the like is very urgent. Therefore, the development of digital, fully automatic, long-distance welding robots is the key point in the technology today.

At present, the welding modes for large-scale precise structures are rail type and infrared control type, the equipment has large volume and complex structure, various additional mechanisms are heavy and inflexible, and the adsorption capacity cannot be combined; in order to ensure the inclination of the groove of the large medium-length thick plate to be fused and deposited to be consistent up and down, the problem of different fusion rates of the upper part and the lower part needs to be solved besides the control of the swinging frequency of a welding gun, so that a welding robot system which is suitable for welding the thick plate with a large structure and can move independently needs to be developed.

Disclosure of Invention

The invention provides a long-distance digital gas melting and gas protecting double-wire welding robot, which aims to provide an autonomous mobile double-wire welding robot device with high efficiency and high quality for welding medium and long thick plates, solves the problem that the motion flexibility and the adsorption capacity of the existing single-wire welding robot cannot be compatible, adopts a double-pulse welding machine, concentrates two sets of digital double-pulse welding machines to improve the efficiency in the long-distance welding process, prolongs the service life of a conductive resistor and a welding gun by improving a cooling system, improves the welding quality by additionally arranging a welding swing mechanism and adopting mixed shielding gas, greatly reduces splashes, reduces the grinding working time and improves the efficiency.

The technical scheme of the invention is as follows: the long-distance digital gas-shielded double-wire welding robot structurally comprises an operation vehicle 1, a welding trolley 3 and a cable 9; the operation vehicle 1 is used for integral control and provides materials and electric power required by welding for the welding trolley 3, the welding trolley 3 is used for controlling stable movement and swing of a welding gun in the welding process, and the operation vehicle 1 and the welding trolley 3 are connected through a cable 9; the cable 9 consists of welding pipes of the wire feeder A11-1 and the wire feeder B11-2, and the tail end of the cable 9 is connected with the double-wire welding gun 8 on the welding trolley 3.

The welding method comprises the following steps:

1) Mounting and fixing run-on plates at two end points of a welding seam of a workpiece to be welded, and mounting a ceramic liner at the bottom of the welding seam;

2) Placing a welding trolley on an arc striking plate at the starting position of a welding seam, starting an operating vehicle, setting welding speed and welding gun swinging frequency according to the thickness of a workpiece and the degree of a welding seam groove, enabling the welding trolley to synchronously move along a track on the welding seam along with the operating vehicle, enabling 2 welding machines to start to give out air and lead wires, and starting welding after arc striking;

3) When the welding trolley moves on a welding seam, the moving process of the trolley is stabilized through the rear guide wheel, the moving direction of the trolley is controlled by the front guide wheel, and the swinging frequency of the twin-wire welding gun in the welding process is controlled by the welding swinging mechanism;

4) The control box monitors and adjusts the movement of the operation vehicle and the welding trolley in real time, the wire feeding speed is controlled, the deviation of the welding trolley in the walking process is reduced, and when the undercut and the deviation of a welding seam are observed, the control box timely corrects the deviation;

5) After one round of welding is finished, adjusting the positions of the operation vehicle and the welding trolley, improving the height of a welding gun, keeping the swinging frequency of the welding gun unchanged, performing the welding process of the steps 2) -4) again until the welding seam is finally finished, and achieving double-sided forming through single-sided welding;

6) When carrying out full position welding, can open strong magnetism ground jack for the welding carriage adsorbs on the welding surface, reaches the all-round welding to curved surface, inclined plane.

The invention has the advantages that:

1) The arrangement mode of the cooling water pipes of the welding gun is adjusted, and the number of the cooling water pipes is reduced, so that the weight of welding equipment and the volume of a connecting pipeline are greatly reduced, the overall weight of the welding gun is reduced by about 1/3, the energy consumption of a welding trolley in a long-distance welding process is reduced, and the comprehensive welding requirements can be met;

2) The power supply of the double-pulse electric welding machine is adopted, and program-controlled digital program control is adopted, so that the efficiency is improved, the deviation can be corrected in time in the welding process, the designed welding swing mechanism enables the swing amplitude of a welding gun to follow the welding process, the quality of a welding seam is high, and the time of a polishing process is reduced;

3) By using Ar-CO ₂ Protective gas is mixed, the service life of a welding gun is prolonged through multipoint cooling, the welding quality is improved, and splashing is reduced;

4) The welding gun nozzle is made of rare earth copper alloy, so that the welding gun nozzle is wear-resistant and good in conductivity, and the inner hole of the conductive nozzle is triangular, so that the welding gun nozzle is suitable for long-time and long-distance welding processes.

Drawings

FIG. 1 is a schematic structural diagram of a long-distance digital gas-shielded twin-wire welding robot.

FIG. 2 is a schematic structural view of the welding carriage.

Fig. 3 isbase:Sub>A sectional viewbase:Sub>A-base:Sub>A of the welding swing mechanism.

FIG. 4 is a schematic view of a twin wire torch.

FIG. 5 is a cross-sectional view B-B of a twin wire torch A welding tube.

Wherein 1 is an operation vehicle, 2 is a bearing base, 3 is a welding trolley, 3-1 is a walking motor, 3-2 is a guide motor, 4 is a rear guide wheel, 5 is a front guide wheel, 6 is a strong magnetic jack, and 7 is a welding swing mechanism; 7-1 is a transmission gear, 7-2 is a swing motor, 7-3 is a sector gear, 7-4 is a screw rod, 7-5 is an upright post, 7-6 is a connecting slide block, 7-7 is a sliding track, 7-8 is a lifting bottom plate, 7-9 is a top limiting plate, and 7-10 is a limiting rod; 8 is a twin-wire welding gun, 8-1 is an A welding pipe, 8-2 is a B welding pipe, 8-3 is a sleeve, 8-4 is a nozzle, 8-1-1 is an A cooling water pipe, 8-1-2 is an A wire feeding air pipe, 8-1-3 is an A wire outlet, 8-1-4 is an A welding pipe outer shell, 8-1-5 is an A welding pipe inner pipe, 8-2-1 is a B cooling water pipe, 8-2-2 is a B wire feeding air pipe, 8-2-3 is a B wire outlet, 8-2-4 is a B welding pipe outer shell, 8-2-5 is a B welding pipe inner pipe, 9 is a cable, 10 is a tuner, 11-1 is an A wire feeder, 11-2 is a B wire feeder, 12-1 is an A welding power supply, 12-2 is a B welding power supply, 13-1 is an A protective gas cylinder, 13-2 is a B protective gas cylinder, 14 is a water tank, 15 is a control box, and 16 is a manual control lever.

Detailed Description

As shown in FIG. 1, the long-distance digital gas-shielded twin-wire welding robot structurally comprises an operation vehicle 1, a welding trolley 3 and a cable 9; the operation vehicle 1 is used for integral control and provides materials and electric power required by welding for the welding trolley 3, the welding trolley 3 is used for controlling stable movement and swing of a welding gun in the welding process, and the operation vehicle 1 and the welding trolley 3 are connected through a cable 9; the cable 9 consists of welding pipes of the wire feeder A11-1 and the wire feeder B11-2, and the tail end of the cable 9 is connected with the double-wire welding gun 8 on the welding trolley 3.

As shown in fig. 2, the operating vehicle 1 structurally comprises a bearing base 2, a tuner 10, an a wire feeder 11-1, a B wire feeder 11-2, an a welding power supply 12-1, a B welding power supply 12-2, an a protective gas cylinder 13-1, a B protective gas cylinder 13-2, a welding gun water tank 14, a control box 15 and a manual control rod 16; wherein the bottom of the bearing base 2 is provided with 2 pairs of travelling wheels, an A protective gas cylinder 13-1 and a B protective gas cylinder 13-2 are arranged at the foremost end of the bearing base 2 in parallel, and Ar-CO is filled in the 2 gas cylinders ₂ Mixing the gas; the control box 15 is arranged at the rear side of the protective gas cylinder; the welding power supply A12-1 and the welding power supply B12-2 are arranged on the rear side of the control box 15, the anode of the welding power supply A12-1 is connected with the wire feeder A11-1 above the welding power supply A, and the cathode of the welding power supply A is grounded; the positive electrode of the welding power supply B12-2 is connected with the wire feeder B11-2 above the welding power supply B, and the negative electrode of the welding power supply B is grounded; the air outlet end of the A protective air bottle 13-1 is connected with the air inlet of the A wire feeder 11-1 through a valve A, and the air outlet end of the B protective air bottle 13-2 is connected with the air inlet of the B wire feeder 11-2 through a valve B; a tuner 10 is arranged between the welding power supply A12-1 and the welding power supply B12-2 and is used for tuning and reducing magnetic interference between the two welding power supplies; the torch water tank 14 is provided at the rearmost end of the carrying base 2.

The control box 15 is respectively connected with a switch of the wire feeder 11-1A, a switch of the wire feeder 11-2B, a switch of the welding power supply 12-1A, a switch of the welding power supply 12-2B, an A valve of the protective gas cylinder 13-1A and a B valve of the protective gas cylinder 13-2B through cables, and is internally provided with a control circuit, a control panel, a PLC and an operating vehicle power supply, is used for digitally controlling the operation of each part of the operating vehicle 1 and the welding trolley 3 and provides power for the movement of the operating vehicle 1; the manual control rod 16 is connected with a movement mechanism of the traveling wheel and is used for manual emergency braking when a fault occurs.

As shown in fig. 3, the welding tractor 3 structurally comprises: a walking motor 3-1, a guide motor 3-2, a rear guide wheel 4, a front guide wheel 5, a strong magnetic jack 6, a welding swing mechanism 7 and a double-wire welding gun 8; wherein, the bottom of the welding trolley is provided with 2 pairs of conveying wheels, a walking motor 3-1 is connected with the 2 pairs of conveying wheels, a rear guide wheel 4 is arranged at the rear end of the welding trolley 3, and a spring is arranged above the rear guide wheel; the front directional wheel 5 is arranged at the front end of the welding trolley 3 and is connected with the guide motor 3-2; the welding swing mechanism 7 is arranged on the body of the welding trolley 3, the rear end is hung with a double-wire welding gun 8, and the strong magnetic jack 6 is arranged between 2 pairs of conveying wheels at the bottom of the welding trolley 3.

As shown in fig. 3-4, the welding swing mechanism 7 structurally comprises a transmission gear 7-1, a swing motor 7-2, a sector gear 7-3, a screw rod 7-4, an upright post 7-5, a connecting slide block 7-6, a sliding track 7-7, a lifting bottom plate 7-8, a top limiting plate 7-9 and a limiting rod 7-10; the swing motor 7-2 is connected with a transmission gear 7-1, the transmission gear 7-1 is meshed with a sector gear 7-3, a limiting hole is formed in the middle of the sector gear 7-3, a rotating shaft at the bottom of the sector gear 7-3 is fixed on the welding trolley 3, and a limiting rod 7-10 penetrates through the limiting hole of the sector gear 7-3 and is fixed with a connecting sliding block 7-6; 4 upright posts 7-5 respectively penetrate through holes at four corners of a lifting bottom plate 7-8 and are fixed on a welding trolley 3, a top limiting plate 7-9 penetrates through the top ends of the 4 upright posts 7-5 and is fixed above the lifting bottom plate 7-8, small holes with threads are oppositely arranged at the right sides of the lifting bottom plate 7-8 and the top limiting plate 7-9, and a screw rod 7-4 penetrates through the small holes on the lifting bottom plate 7-8 and the top limiting plate 7-9 and is fixed; the sliding track 7-7 is arranged on the upper side of the lifting bottom plate 7-8, and the connecting slide block 7-6 is embedded with the sliding track 7-7 through a sliding groove.

The method for regulating and controlling the swing amplitude of the twin-wire welding gun 8 by the welding swing mechanism 7 comprises the following steps: the swing motor 7-2 controls the transmission gear 7-1 to drive the sector gear 7-3 to perform reciprocating motion of left-right swing, and the sector gear 7-3 drives the connecting slide block 7-6 connected with the limiting rod 7-10 to move transversely on the sliding track 7-7 so as to drive the twin-wire welding gun 8 to swing synchronously; the height of the lifting bottom plate 7-8 is adjusted by rotating the screw rod 7-4, so that the swing amplitude of the connecting slide block 7-6 is increased, and the swing amplitude of the twin-wire welding gun 8 is increased accordingly; the maximum swing amplitude of the connecting slide block 7-6 on the sliding track 7-7 is limited by the top limiting plate 7-9 and the 4 upright posts 7-5, and meanwhile, the stability of the whole welding swing mechanism 7 is improved.

As shown in FIG. 4, the twin-wire welding gun 8 comprises a welding pipe A8-1, a welding pipe B8-2, a sleeve 8-3, a nozzle 8-4, a nozzle cooling water inlet pipe 14-1, a nozzle cooling water outlet pipe 14-2 and a nozzle cooling sleeve 14-3; the welding device comprises a welding pipe A, a welding pipe B, a sleeve 8-3, a nozzle cooling sleeve 14-3, a nozzle cooling water inlet pipe 14-1, a nozzle cooling water outlet pipe 14-2, a nozzle cooling sleeve 14-3 and a welding gun water tank 14, wherein the welding pipe A8-1 and the welding pipe B8-2 are arranged in parallel, the sleeve 8-3 is arranged outside the welding pipe A8-1 and the welding pipe B8-2, the nozzle 8-4 is arranged at the top end of a twin-wire welding gun 8, and the nozzle cooling sleeve 14-3 is arranged outside the nozzle 8-4; the nozzles 8-4 are made of rare earth copper alloy, so that the conductivity is good, and the inner holes are triangular, so that the welding process can be suitable for long-time and long-distance welding.

As shown in fig. 4-5, the welding pipe a 8-1 includes a cooling water pipe a 8-1, a wire feeding air pipe a 8-1-2, a wire outlet 8-1-3, a welding pipe outer shell 8-1-4, and a welding pipe inner pipe a 8-1-5; wherein the A wire feeding air supply pipe 8-1-2 is arranged at the center of the A welding pipe 8-1, the A wire feeding air supply pipe 8-1-2 is externally provided with an A welding pipe inner pipe 8-1-5, the A welding pipe inner pipe 8-1-5 is externally provided with an A cooling water pipe 8-1-1, and the outermost layer of the A cooling water pipe 8-1-1 is an A welding pipe outer shell 8-1-4; a part of the A cooling water pipe 8-1-1 penetrates through the pipe wall of the A welding pipe inner pipe 8-1-5 and is close to the A wire feeding air supply pipe 8-1-2; the A wire outlet 8-1-3 is arranged at the tail end of the A welding pipe 8-1.

The B welding pipe 8-2 comprises a B cooling water pipe 8-2-1, a B wire feeding air supply pipe 8-2, a B wire outlet 8-2-3, a B welding pipe outer shell 8-2-4 and a B welding pipe inner pipe 8-2-5; wherein the B wire feeding air supply pipe 8-2-2 is arranged at the center of the B welding pipe 8-2, the B welding pipe inner pipe 8-2-5 is arranged outside the B wire feeding air supply pipe 8-2-2, the B cooling water pipe 8-2-1 is arranged outside the B welding pipe inner pipe 8-2-5, and the B welding pipe outer shell 8-2-4 is arranged at the outermost layer of the B cooling water pipe 8-2-1; a part of the cooling water pipe 8-2-1 of the B passes through the pipe wall of the inner pipe 8-2-5 of the welding pipe B and is close to the wire feeding air supply pipe 8-2-2 of the B; the B wire outlet 8-2-3 is arranged at the tail end of the B welding pipe 8-2.

A. B, transforming the cooling water pipe in the welding pipe: will originally establish 4 condenser tube (2 inlet tube, outlet pipe to the UNICOM) of intraductal, outer both sides respectively in the welding pipe simplify to 1 to condenser tube, through buckling condenser tube's structure for condenser tube can cool off welding pipe outer wall and inside send a blast pipe simultaneously, has not only reduced the whole weight and the volume of welding pipe, has also reduced the demand of long distance welding to material and energy consumption, improves long distance welded efficiency from each side.

The model that strong magnetic jack 6 adopted is strong magnetic jack of high magnetism 10SH, can adjust magnetic strength according to the welding condition for welding carriage 3 can hug closely the welding surface action, and does not lose removal and wobbling flexibility, adsorbs freely, conveniently, has overcome the various mechanisms that install additional among the prior art heavy, the dumb, the problem that adsorption capacity can not have concurrently, can make welding process more smooth.

The A wire feeder 11-1 and the B wire feeder 11-2 adopt MIG/MAG-TANE double-pulse welding wire feeders, 2 welding machines adopt indirect working frequency and same-frequency phase difference of 180 degrees, and meanwhile, the tuner 10 is adopted to reduce electromagnetic interference and improve working efficiency.

The long-distance digital gas-shielded double-wire welding robot comprises the following operation steps:

1) Mounting and fixing run-on plates at two end points of a welding joint of a workpiece to be welded, and mounting ceramic liners at the bottom of the welding joint;

2) Placing a welding trolley at the starting position of a welding seam, starting an operation vehicle, setting welding speed and welding gun swinging frequency according to the thickness of a workpiece and the degree of a welding seam groove, enabling the welding trolley to synchronously move along a track on the welding seam along with the operation vehicle, enabling 2 welding machines to start to give out air and lead wires, and starting welding after arc striking;

5) After one round of welding is finished, adjusting the positions of the operation vehicle and the welding trolley, improving the height of the welding gun, keeping the swing frequency of the welding gun unchanged, performing the welding process of the steps 2) to 4) again until the welding seam is finally finished, and achieving double-sided forming through single-sided welding;

6) When the all-position welding is carried out, the strong magnetic jack can be opened, so that the welding trolley is adsorbed on the welding surface, and the all-dimensional welding of the curved surface and the inclined surface is achieved.

Claims

1. The long-distance digital gas-shielded double-wire welding robot is characterized by comprising an operation vehicle, a welding trolley and a cable; the operation vehicle is used for integral control and provides materials and electric power required by welding for the welding trolley, the welding trolley is used for controlling the stable movement and swing of a welding gun in the welding process, and the operation vehicle is connected with the welding trolley through a cable; the cable consists of welding pipes of a wire feeder A and a wire feeder B, and the tail end of the cable is connected with a double-wire welding gun on the welding trolley;

the welding tractor includes: the welding device comprises a walking motor, a guide motor, a rear guide wheel, a front directional wheel, a strong magnetic jack, a welding swing mechanism and a double-wire welding gun; wherein, the bottom of the welding trolley is provided with 2 pairs of conveying wheels, the walking motor is connected with the 2 pairs of conveying wheels, the rear guide wheel is arranged at the rear end of the welding trolley, and a spring is arranged above the rear guide wheel; the front directional wheel is arranged at the front end of the welding trolley and is connected with a guide motor; the welding swing mechanism is arranged on the body of the welding trolley, a double-wire welding gun is hung at the rear end of the welding swing mechanism, and the strong magnetic jack is arranged between 2 pairs of conveying wheels at the bottom of the welding trolley;

the operation vehicle comprises a bearing base, a tuner, an A wire feeder, a B wire feeder, an A welding power supply, a B welding power supply, an A protective gas cylinder, a B protective gas cylinder, a welding gun water tank, a control box and a manual control rod; wherein the bottom of the bearing base is provided with 2 pairs of travelling wheels, the A protective gas cylinder and the B protective gas cylinder are arranged at the foremost end of the bearing base in parallel, and the control box is arranged at the rear side of the protective gas cylinder; the welding power supply A and the welding power supply B are arranged on the rear side of the control box, the anode of the welding power supply A is connected with the wire feeder A above the welding power supply A, and the cathode of the welding power supply A is grounded; the positive electrode of the welding power supply B is connected with the wire feeder B above the welding power supply B, and the negative electrode of the welding power supply B is grounded; the air outlet end of the A protective gas cylinder is connected with the air inlet of the A wire feeder through a valve A, and the air outlet end of the B protective gas cylinder is connected with the air inlet of the B wire feeder through a valve B; a tuner is arranged between the welding power supply A and the welding power supply B; the welding gun water tank is arranged at the rearmost end of the bearing base; the control box is respectively connected with a switch of the wire feeder A, a switch of the wire feeder B, a switch of the welding power supply A, a switch of the welding power supply B, an A valve of the protective gas cylinder A and a B valve of the protective gas cylinder B through cables; the manual control rod is connected with a motion mechanism of the traveling wheel;

the double-wire welding gun comprises a welding pipe A, a welding pipe B, a sleeve, a nozzle cooling water inlet pipe, a nozzle cooling water outlet pipe and a nozzle cooling sleeve; the welding gun comprises a welding pipe A, a welding pipe B, a sleeve pipe, a nozzle cooling water inlet pipe and a nozzle cooling water outlet pipe, wherein the welding pipe A and the welding pipe B are arranged in parallel;

the welding swing mechanism comprises a transmission gear, a swing motor, a sector gear, a screw rod, an upright post, a connecting slide block, a sliding track, a lifting bottom plate, a top limiting plate and a limiting rod; the swing motor is connected with a transmission gear, the transmission gear is meshed with the sector gear, a limiting hole is formed in the middle of the sector gear, a rotating shaft at the bottom of the sector gear is fixed on the welding trolley, and a limiting rod penetrates through the limiting hole of the sector gear and is fixed with the connecting sliding block; the 4 stand columns respectively penetrate through holes in four corners of the lifting bottom plate and are fixed on the welding trolley, the top limiting plate penetrates through the top ends of the 4 stand columns and is fixed above the lifting bottom plate, small holes with threads are oppositely formed in the right sides of the lifting bottom plate and the top limiting plate, and the screw rod penetrates through the small holes in the lifting bottom plate and the top limiting plate and is fixed; the sliding rail is arranged on the upper side of the lifting bottom plate, and the connecting sliding block is embedded with the sliding rail through the sliding groove.

2. The long-range digital melting gas-shielded twin-wire welding robot as claimed in claim 1, wherein the A welding pipe comprises an A cooling water pipe, an A wire feeding air pipe, an A wire outlet, an A welding pipe outer shell and an A welding pipe inner pipe; the A wire feeding air supply pipe is arranged in the center of the A welding pipe, the A welding pipe inner pipe is arranged outside the A wire feeding air supply pipe, the A cooling water pipe is arranged outside the A welding pipe inner pipe, and the outermost layer of the A cooling water pipe is a welding pipe shell; a part of the cooling water pipe A passes through the pipe wall of the inner pipe of the welding pipe A and is close to the wire feeding air pipe A; the A wire outlet is arranged at the tail end of the A welding pipe.

3. The long-distance digital melting gas-shielded twin wire welding robot according to claim 1, wherein the B welding pipe comprises a B cooling water pipe, a B wire feeding air pipe, a B wire outlet, a B welding pipe outer shell and a B welding pipe inner pipe; the B wire feeding air supply pipe is arranged in the center of the B welding pipe, the B welding pipe inner pipe is arranged outside the B wire feeding air supply pipe, the B cooling water pipe is arranged outside the B welding pipe inner pipe, and the outermost layer of the B cooling water pipe is a B welding pipe shell; a part of the cooling water pipe B passes through the pipe wall of the inner pipe of the welding pipe B and is close to the wire feeding air pipe B; the B wire outlet is arranged at the tail end of the B welding pipe.

4. A welding method using the long-distance digital molten gas shielded twin wire welding robot according to claim 1, characterized in that the method comprises the steps of:

5) After one round of welding is finished, adjusting the positions of the operation vehicle and the welding trolley, increasing the height of the welding gun, keeping the swing frequency of the welding gun unchanged, performing the welding process of the step 2) 4) again until the welding seam is finally finished, and achieving double-sided forming through single-sided welding;