Arc welding method
A consumable electrode type arc welding method for generating arc between a plate-shaped work and a welding wire by a mixed shield gas including argon gas to weld the plate-shaped work, includes: making a state of reverse polarity in which the polarity of the welding wire is positive at the welding start time, and switching at least once to a state of positive polarity in which the polarity of the welding wire is negative.
1. A consumable electrode type arc welding method for generating arc between a plate-shaped work and a welding wire by a mixed shield gas including argon gas to weld the plate-shaped work, comprising:
starting a welding while making a polarity state into a reverse electrical polarity state (EP) in which an electrical polarity of the welding wire is positive; continuing the welding while maintaining the reverse electrical polarity state before a welding wire feeding speed reaches 25 m/min; and
switching, after welding wire feeding speed reaches 25 m/min, at least once the electrical polarity state from the reverse electrical polarity state to a positive electrical polarity state (EN) in which the electrical polarity of the welding wire is negative,
wherein a welding current is 600 A or more.
2. The arc welding method according to claim 1 , wherein
when a welding-wire feeding speed is below 25 m/min., a state of reverse electrical polarity is made, and
when the welding-wire feeding speed is 25 m/min or more, the state of reverse electrical polarity is switched to the state of positive electrical polarity.
3. The arc welding method according to claim 2 , wherein
the thickness of the plate-shaped work is 8 mm or more, the wire diameter of the welding wire is 1.2 to 1.6 mm.
4. The arc welding method according to claim 1 , wherein
the state of reverse electrical polarity is switched to the state of positive electrical polarity after several seconds has passed after the welding-wire feeding starts.
5. The arc welding method according to claim 4 , wherein the thickness of the plate-shaped work is 8 mm or more, the wire diameter of the welding wire is 1.2 to 1.6 mm.
6. The arc welding method according to claim 1 , wherein
the thickness of the plate-shaped work is 8 mm or more, the wire diameter of the welding wire is 1.2 to 1.6 mm.
7. The method of claim 1 , wherein a wire tip droplet and en electric arc do not rotate.
8. A consumable electrode type arc welding method for generating arc between a plate-shaped work and a welding wire by a mixed shield gas including argon gas to weld the plate-shaped work, comprising:
making a state of reverse electrical polarity in which the electrical polarity of the welding wire is positive at the welding start time, and
switching at least once to a state of positive electrical polarity in which the electrical polarity of the welding wire is negative and
a welding current is 600 A or more,
wherein
the state of reverse electrical polarity is switched to the state of positive electrical polarity after several seconds has passed after the welding-wire feeding starts
wherein
switching the state of reverse electrical polarity to the state of positive electrical polarity, when the welding-wire feeding speed is 25 m/min. or more, or after several seconds has passed since the welding-wire feeding starts, and
repeating to switch the state of positive electrical polarity to the state of reverse electrical polarity at a frequency of 10 Hz or more.
9. The arc welding method according to claim 8 , wherein
the thickness of the plate-shaped work is 8 mm or more, the wire diameter of the welding wire is 1.2 to 1.6 mm.
10. The method of claim 8 , wherein a wire tip droplet and en electric arc do not rotate.