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Welding economy
The use of ceramic backing offers significant econo-
mic advantages. Take a look at a couple of examples
based on labour cost and time to complete the job.
Switching from MMA to FCAW with Elga Cera-
mic Backing
In this example we have used an average welding
speed (55 mm/min for MMA and 150 mm/min for
FCAW with backing) and a labour cost of 40€/h
for the welder.
Using a 2,5 mm electrode:
Typical deposition rate is 0,6-0,7 kg/h.
Welding speed 40-70 mm/min.
Characteristic of MMA is a low arcing time factor.
With a 2,5 mm electrode, only a 50-70 mm weld
length can be achieved between electrode changes.
Flux cored wire and backing (single-sided
welding):
Switching from two-sided welding to single-
sided with flux cored wire and ceramic
backing
Labour cost
€/ m
1. Back-gouging
3. Rewelding on the re-
verse side, depending on
the construction.
Substantially higher
productivity since all
”extra work” has been
eliminated.
2. Grinding
Two-sided welding
means additional
time for:
Single-sided welding
with flux cored wire
and backing:
Two-sided welding Single-sided welding
with backing
0
20
40
60
80
100
120
MMA
FCAW with backing
Typical deposition rate is 2,5-3,0 kg/h.
Welding speed 100-200 mm/min.
Characteristic of flux cored wire with backing is a
very high arcing time factor. A 1 meter long root
pass can be welded non-stop.
Total time comparison
0
10
20
30
40
50
60
70
80
90
100
12
Rewelding of reverse side
Gouging & grinding
Mounting of backing
Root welding