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Deposition data
Covered electrodes
•Electrode efficiency or metal recovery: The
weight of weld metal deposited in relation to
the weight of core wire consumed.
An electrode without any iron powder in the coating
gives a recovery factor of about 90%. The loss oc-
curs as spatter onto the plate and oxidation losses
into the slag covering.
With iron powder added to the coating the metal
recovery can be increased. Electrodes with a reco-
very factor above about 130% are normally termed
”high recovery”. A common high recovery figure
is around 180%, but there are electrodes giving
recoveries of up to 250%.
Elga’s mild steel high recovery electrodes are called
MAXETA.
e.g. Maxeta 10 135%
Maxeta 11 190%
Maxeta 21 170%
Maxeta 22 240%
•Deposition Coefficient N: The weight of weld
metal deposited in relation to the weight of
electrode consumed.
For covered electrodes N is normally around 0.7 i.e.
if you weld 1 kg of electrodes you end up with 0.7
kg of weld metal. N is useful when calculating the
electrode consumption.
e.g. If 5 kg of weld metal is required to complete a
given job, then the actual electrode consumption
would be 5 ÷ 0.7 = 7.1 kg
•Productivity: The weight of weld metal depo-
sited per hour arc time
The higher the welding current that can be used on
any job, the higher is the productivity. All deposi-
tion data given in this catalogue have been obtained
using the maximum recommended current for the
electrode. Use of a larger diameter electrode results
in increased productivity as does using electrodes
with iron powder in the coating.
e.g. P 43 Ø 3.25 : H = 1.2 kg/h
P 43 Ø 5.0 : H = 2.7 kg/h
Maxeta 11 Ø 3,25 : H = 2.5 kg/h
Maxeta 11 Ø 5.0 : H = 5.3 kg/h
Cored Wires
The deposition coefficient for a cored wire varies
between 0.85-0.95, depending on the different types
i.e. deposition efficiency is between 85-95%. The
exact efficiency figure for each cored wire is indica-
ted on the respective product page in the catalogue,
together with a deposition productivity diagram.
Solid Wires
The deposition coefficient for a solid wire is about
0.96.