Circ Seam Milling Machines for narrow-gap preparation of the welding seam
Graebener gained its experiences during the period when it ran its own pipe mill. It was a major task to produce extremely long piles. The importance of a clean and fast preparation of external circumferential weld seams on pipes, vessels, and apparatus became apparent. For this reason, the Graebener longitudinal and circumferential milling machines were developed. The longitudinally welded shells are used to produce apparatus, reactors, pipe constructions, dolphins and spud piles. They are internally submerged-arc welded, milled from the outside and then welded from the outside.
Circumferential milling can sometimes reduce the costs for one meter weld seam by more than 50 %. This is, on the one hand, due to a reduction of the time necessary to prepare the weld seam and, on the other hand, due to the reduced weld metal volume being applied, as well as the reduction of the welding time. The machines are equipped with a sensor system which automatically follows the ovality of the pipe, thus guaranteeing a constant seam depth (seam geometry).
Various models of Graebener circ seam milling machines are available for three different milling depths, with and without undercarriage.
|GRF 30||GRF 45||GRF 55||GRF 45-V||GRF 55-V|
|Capacity||30 kW||45 kW||55 kW||45 kW||55 kW|
|Milling depth up to||60 mm||100 mm||100 mm||125 mm|
|Transport||shop crane, fork lift||with carriage on rails|
Portable integrated circular seam milling machine