ESAB offers complete solutions for longitudinal pipe mills including tack welding, ID welding and OD welding.
Tack welding equipment (MAG welding in forming station)
The tack welding equipment consists of a heavy duty welding torch for MAG welding equipped with a gas nozzle for high-flow gas protection. The feeding of the welding wire is handled by a push-pull system, equipped with ESAB's well-known A6 VEC motors. The power sources used are two 1600A welding rectifiers, connected in parallel.
The ID welding station features an 18.5-meter-long internal boom for vertical operation in 20 inch diameter pipes. A 4-wire welding head is mounted at the tip of the boom. The welding head has a laser joint-tracking system which activates a slide cross with a 60x60 mm stroke. The welding head also has a support wheel to stabilize the ID boom against the pipe. The wire feeding system is of the "push-pull" type, motors being mounted at the welding head and at the rear of the boom.
The OD welding station is built on a semi-stationary column and boom supporting a 5-wire welding head. As the space for the welding head on the OD station is not so limited the wire feeders are mounted in a "rainbow" configuration enabling the wireliners between the contact nozzles and wire feed motors being straight.
The earthing system for both the internal and external welding stations are of a brush rack system. Each rack has 12 brushes and are held against the pipe by means of a pneumatic column & boom. After each completed weld, the rack with brushes are lifted up so that the pipe can be transported away from the welding station.