Submerged Arc Welding Technical Handbook - Esab

OK Flux 10.72 - Wind towers,
pressure vessels and general
construction
pt
OK Flux 10.72 is designed for multi-run fillet and butt
welding and provides reliable low-temperature toughness at
fabricators to increase productivity further with four-wire and
tandem-twin arc welding. The flux is well established in wind
tower fabrication, but also in the manufacturing of pressure
vessels, penstocks and in general fabrication.
Tandem-twin – a major step forward.
The development of tandem-twin SAW coincided with the
development of OK Flux 10.72. The process brings welding
productivity to new levels. It can be used for all welds with
most importantly the circumferential welds that make up the
majority in wind tower fabrication. OK Flux 10.72 is capable
of accommodating the high deposition rate of the tandemtwin
process. The table on this page compares the
deposition rates for various SAW techniques and shows the
superior productivity from the tandem-twin process.
Productivity can be further increased by reducing the joint
included angle from 60 to 50°, enabled by the excellent slag
detachability in narrow joints of OK Flux 10.72. Comparing a
50° joint welded with tandem twin (19% joint volume), it can
be calculated that the arc time is almost halved (see
Svetsaren 2/2005 p.16).
Comparison of deposition rates for various
SAW techniques.
SAW process Wire combination Deposition rate at 100% duty
cycle
Single wire 1 x 4.0 mm 12 kg/h
Twin-wire 2 x 2.5 mm 15 kg/h
Tandem wire 2 x 4.0 mm 25 kg/h
Tandem-Twin 4 x 2.5 mm 38 kg/h
Reduction of joint cross section by reduced opening angle,
using OK Flux 10.72
Plate thickness
Cross section
Y- joint 60°
Cross section
Y- joint 50°
(mm) 5mm land, no gap (mm 2 ) 5mm land, no gap (mm 2 ) (%)
25 231 187 -19
35 520 420 -19
45 924 746 -19
Reduction
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