CO2 gas shielded welding operation manual, classic in the classic!
Release time:
2022-08-26
【Summary Description】 1. Arc. (1) Keep the length unchanged. (2) Reverse arc ignition method, 10-20mm at the front end of the weld. (3) The joint is worn thin to prevent the joint from melting and. 2. Arc shape. (1) Keep the length unchanged. (2) Arc at the edge of the molten pool. Arc starting and arc extinguishing technology, CO2 arc starting is simple, but if you want to achieve certain quality requirements, you must master the standard operating procedures. Arc process: Press the welding torch switch before the arc, while maintaining a certain distance between the end of the welding wire and the base metal. When arcing, keep the dry elongation stable. When the temperature of the workpiece is low, the arc cannot be preheated for a long time like manual welding, so the reverse arc ignition method should be adopted to make the weld fully. Arc process: when CO2 welding arc, the dry elongation should be kept unchanged, and the ignition point should be pulled to the edge of the molten pool to stop the arc, so that the welding machine can self-complete the arc process of burning back, ball and delay gas protection. 3. Method of operation. (1) Left welding method (right→left): small height, large width, small spatter, easy observation of the weld, stable welding process, good gas protection effect (non-ferrous metals must be welded on the left), but the solution depth is shallow. (2) Right welding method (from left to right): relatively high, small width, large spatter, easy to observe the molten pool, penetration. (3) Transport gun method: sawtooth swing grab. (4) fillet welding does not swing or swing slightly. (5) vertical angle upward welding, using triangular spray gun. (6) Welding torch transition: stay on both sides of the molten pool, and the transition point is located at 1/3 of the front of the molten pool. (7) Spray gun angle: perpendicular to the weld bead, at an angle of 80-90 ° along the direction of the spray gun. (8) Test plate: the gap is 2.0-2.5mm, and the arc point is slightly smaller than the arc. No blunt edge, 1 ° deformation resistance. 4. Welding parameters. (1) Current and voltage. U = 14 0.05I(U is the voltage I am current). The welding current should be selected correctly according to the thickness of the base metal, the type of joint and the diameter of the welding wire. During short-circuit transition, under the premise of ensuring welding penetration, try to choose a small current, because when the current is too large, it is easy to cause the pool to roll, not only the spatter is large, but also the formability is very poor. The welding voltage must be well matched to the current. Welding voltage is too high or too low will cause spatter, welding voltage should be increased with the increase of welding current, should be reduced with the decrease of welding current, the best welding voltage is generally between 1-2V, so. Welding voltage should be carefully adjusted. Excessive current: arc length, large splash, the feeling of top hand, the ratio is too high, and the two sides are not well integrated. High voltage: the arc is long, the spatter is a bit large, the current is unstable, how high is too small, every time the welding is too wide, the arc ignition is easy to burn the conductive nozzle. (2) dry elongation. The length of the wire out of the contact nozzle is the dry elongation, the general empirical formula is I =(10~20)d, try to keep it within the range of 10~20mm. When the norm is large, it is slightly larger. Standard hours, slightly smaller. Dry stretching is too long: When the length of the welding wire is too long, the greater the resistance of the welding wire, the faster the welding wire melting speed, which is easy to cause the welding wire to fuse, splash, large melting depth, and unstable arc combustion. At the same time, the gas protection effect is not good. Dry stretching too short: easy to burn the conductive nozzle. At the same time, the conductive nozzle is easy to clamp when heated. The spatter can easily clog the nozzle. Deep melt. (3) Gas flow. Filament welding is (5-15) L/min, thick wire welding L =(20-25)I/min Excessive: turbulence is generated, air intrusion is caused, and air holes are generated. Too small: gas protection is not good. Wind speed ≤ 2 m/s is not affected. Measures shall be taken when the wind speed is ≥ 2 m/s. Increase gas flow. Take wind measures. Note: When air leakage occurs, it will cause pores in the weld. The air leakage point must be treated and cannot be supplemented by increasing the flow rate. (4) Arc force. When different thickness, different position, different specifications, different welding wire, choose different arc force. Big: hard arc, big splash. Too small: soft arc, small splash. (5) The pressure. Over-tightening: the wire is deformed and the wire feeding is unstable. Too loose: the steel wire slips and the steel wire is delivered slowly. (6) Power supply polarity. DC reverse polarity: large penetration, small spatter, good arc stability of weld formation, low hydrogen content of weld. DC positive: under the same conditions, the welding wire melting speed. It is 1.6 times the opposite polarity, the melting depth is large, how high, and the splash is large. For surfacing, cast iron repair welding, high-speed welding. (7) welding speed. When the current and voltage are constant, the welding speed has an important influence on the internal and external quality of the weld. Too fast welding speed: penetration, width, residual height reduction, projection welding or humping bead, weld toe bite. When the welding speed is too fast, it will destroy the gas protection effect and easily produce pores. At the same time, the cooling rate will be accelerated, so the plasticity and toughness of the weld metal will be reduced. And it will make the middle of the welding encounter an edge, resulting in poor forming. The welding speed is too slow: the molten pool becomes larger, the weld seam becomes wider, and the weld toe is full. The welding speed is slow, and it is easy to discharge the gas in the molten pool. Overheating can cause the weld metal structure to be rough or burn through. The welding parameters shall be selected according to the following conditions: the weld is beautiful in appearance and free of defects such as burn through, undercut, pores and cracks. The penetration depth is controlled within an appropriate range. The welding process is stable and the spatter is small. The sound of sand when welding. At the same time, it should have the highest productivity.
1. Arc.
(1) Keep the length unchanged.
(2) Reverse arc ignition method, 10-20mm at the front end of the weld.
(3) The joint is worn thin to prevent the joint from melting and.
2. Arc shape.
(1) Keep the length unchanged.
(2) Arc at the edge of the molten pool.
Arc starting and arc extinguishing technology, CO2 arc starting is simple, but if you want to achieve certain quality requirements, you must master the standard operating procedures.
Arc process: Press the welding torch switch before the arc, while maintaining a certain distance between the end of the welding wire and the base metal.
When arcing, keep the dry elongation stable. When the temperature of the workpiece is low, the arc cannot be preheated for a long time like manual welding, so the reverse arc ignition method should be adopted to make the weld fully.
Arc process: when CO2 welding arc, the dry elongation should be kept unchanged, and the ignition point should be pulled to the edge of the molten pool to stop the arc, so that the welding machine can self-complete the arc process of burning back, ball and delay gas protection.
3. Method of operation.
(1) Left welding method (right→left): small height, large width, small spatter, easy observation of the weld, stable welding process, good gas protection effect (non-ferrous metals must be welded on the left), but the solution depth is shallow.
(2) Right welding method (from left to right): relatively high, small width, large spatter, easy to observe the molten pool, penetration.
(3) Transport gun method: sawtooth swing grab.
(4) fillet welding does not swing or swing slightly.
(5) vertical angle upward welding, using triangular spray gun.
(6) Welding torch transition: stay on both sides of the molten pool, and the transition point is located at 1/3 of the front of the molten pool.
(7) Spray gun angle: perpendicular to the weld bead, at an angle of 80-90 ° along the direction of the spray gun.
(8) Test plate: the gap is 2.0-2.5mm, and the arc point is slightly smaller than the arc. No blunt edge, 1 ° deformation resistance.
4. Welding parameters.
(1) Current and voltage.
U = 14 0.05I(U is the voltage I am current).
The welding current should be selected correctly according to the thickness of the base metal, the type of joint and the diameter of the welding wire. During short-circuit transition, under the premise of ensuring welding penetration, try to choose a small current, because when the current is too large, it is easy to cause the pool to roll, not only the spatter is large, but also the formability is very poor.
The welding voltage must be well matched to the current. Welding voltage is too high or too low will cause spatter, welding voltage should be increased with the increase of welding current, should be reduced with the decrease of welding current, the best welding voltage is generally between 1-2V, so.
Welding voltage should be carefully adjusted.
Excessive current: arc length, large splash, the feeling of top hand, the ratio is too high, and the two sides are not well integrated.
High voltage: the arc is long, the spatter is a bit large, the current is unstable, how high is too small, every time the welding is too wide, the arc ignition is easy to burn the conductive nozzle.
(2) dry elongation.
The length of the wire out of the contact nozzle is the dry elongation, the general empirical formula is I =(10~20)d, try to keep it within the range of 10~20mm. When the norm is large, it is slightly larger. Standard hours, slightly smaller.
Dry stretching is too long: When the length of the welding wire is too long, the greater the resistance of the welding wire, the faster the welding wire melting speed, which is easy to cause the welding wire to fuse, splash, large melting depth, and unstable arc combustion. At the same time, the gas protection effect is not good.
Dry stretching too short: easy to burn the conductive nozzle. At the same time, the conductive nozzle is easy to clamp when heated. The spatter can easily clog the nozzle. Deep melt.
(3) Gas flow.
Filament welding is (5-15) L/min, thick wire welding L =(20-25)I/min
Excessive: turbulence is generated, air intrusion is caused, and air holes are generated.
Too small: gas protection is not good.
Wind speed ≤ 2 m/s is not affected.
Measures shall be taken when the wind speed is ≥ 2 m/s.
Increase gas flow. Take wind measures.
Note: When air leakage occurs, it will cause pores in the weld. The air leakage point must be treated and cannot be supplemented by increasing the flow rate.
(4) Arc force.
When different thickness, different position, different specifications, different welding wire, choose different arc force.
Big: hard arc, big splash.
Too small: soft arc, small splash.
(5) The pressure.
Over-tightening: the wire is deformed and the wire feeding is unstable.
Too loose: the steel wire slips and the steel wire is delivered slowly.
(6) Power supply polarity.
DC reverse polarity: large penetration, small spatter, good arc stability of weld formation, low hydrogen content of weld. DC positive: under the same conditions, the welding wire melting speed. It is 1.6 times the opposite polarity, the melting depth is large, how high, and the splash is large. For surfacing, cast iron repair welding, high-speed welding.
(7) welding speed.
When the current and voltage are constant, the welding speed has an important influence on the internal and external quality of the weld.
Too fast welding speed: penetration, width, residual height reduction, projection welding or humping bead, weld toe bite. When the welding speed is too fast, it will destroy the gas protection effect and easily produce pores. At the same time, the cooling rate will be accelerated, so the plasticity and toughness of the weld metal will be reduced. And it will make the middle of the welding encounter an edge, resulting in poor forming.
The welding speed is too slow: the molten pool becomes larger, the weld seam becomes wider, and the weld toe is full. The welding speed is slow, and it is easy to discharge the gas in the molten pool. Overheating can cause the weld metal structure to be rough or burn through.
The welding parameters shall be selected according to the following conditions: the weld is beautiful in appearance and free of defects such as burn through, undercut, pores and cracks. The penetration depth is controlled within an appropriate range. The welding process is stable and the spatter is small. The sound of sand when welding. At the same time, it should have the highest productivity.
Related News
Telephone:+86-18594983359
E-mail:Firmkim@cn-huaguang.com
Zip Code: 311112
Address: No. 82, Qihang Road, Renhe Street, Yuhang District, Hangzhou City, Zhejiang Province
Douyin QR code
We chat number
WeChat public account