Types of packaging
Electrodes in packaging type A must be stored
with the plastic wrapping unbroken in a climatically
controlled environment according to the above. If
low hydrogen weld metal is specified then electrodes
in packaging type A must be re-dried before use,
following the instructions in the data sheet or on
the label.
Elga’s non-alloy and low alloy electrodes are supplied in two different types of packaging, depending
on the required level of resistance to moisture pickup from the atmosphere in the unopened condition.
A) Cardboard box with shrink plastic wrapping.
This is the most common packaging for electrode
type 1 and type 2 non-alloy C-Mn electrodes.
B) Hermetically sealed steel can or aluminiumlaminated plastic foil vacuum pack (DryPac). This
is the most common packaging for type 3 stainless
electrodes and type 2 low alloy electrodes.
Electrodes in packaging type B are completely
moisture diffusion-proof and do not therefore require any special storage instructions. Electrodes
taken directly from newly opened packaging of this
type do not require re-drying before use.
To avoid condensation forming on electrodes that
have been stored at a lower temperature than ambient, unopened packaging should be allowed to
reach ambient temperature before being opened,
independent of packaging type.
Of these two packaging forms, it is only for type B
that Elga guarantees low moisture content at point
of opening. Products delivered in packaging type A
are guaranteed to have been tested to comply with
low moisture content following final baking in the
factory, but no guarantee can be given that they have
not subsequently picked up moisture during delivery
to, or storage at, the customer. Electrodes in type A
packaging must therefore be re-dried before use if
low hydrogen weld metal is specified.
Type 2 and 3 electrodes from opened packaging can be stored in a storage cabinet held at
105-150 °C without the risk of moisture pick-up.
It is important here that these electrodes are not
mixed together with type 1 electrodes in the same
cabinet, because the latter can transfer moisture to
the former.
Points to consider when handling and
storing unopened packaging
Handling in the workshop
Storage
Elga’s type 2 and 3 electrodes are manufactured
according to the MR-design concept (Moisture Resistant) which ensures low initial moisture content
together with a slow moisture pick-up rate.
In general, moisture pick-up of electrodes depends
on the temperature and humidity of the surrounding
atmosphere, which can be measured as the relative
humidity (RH) at a given temperature.
However, moisture pick-up occurs relatively slowly
with storage under the following conditions:
5-15 °C
15-25 °C
>25 °C
For electrodes in type B packaging the following
exposure times are valid for conditions of 26.7 °C
and 80% RH, in order to guarantee low hydrogen
level in the weld metal or sufficiently low moisture
content in the coating (stainless electrodes).
<60% RH
<50% RH
<40% RH
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