Specifications

8
317AU : IPRM 2007 : SECTION 8 : CONSUMABLES
WARNING Welding can give rise to electric shock, excessive noise, eye and skin burns due to the arc rays, and a potential health hazard if you breathe in the emitted fumes and gases.
Read all the manufacturer’s instructions to achieve the correct welding conditions and ask your employer for the Materials Safety Data Sheets. Refer to www.boc.com.au or www.boc.co.nz
Fundamentals of Manual Metal Arc (MMA) Welding
Practical Considerations
Storage and Re-drying
MMA electrodes should be stored in dry, well-ventilated and
preferably heated stores. For critical applications it is also
recommended that they be held in temperature and humidity
controlled conditions, maintaining humidity below 60%RH (Relative
Humidity) and a temperature above the dew point to avoid
moisture condensing onto the electrodes. Electrodes held in dry
conditions will remain in prime condition for several years, but if the
coating absorbs moisture, this will lead to a gradual deterioration.
Evidence of deterioration includes the presence of white powdery
areas on the surface of the coating, cracks in the coating or missing
pieces of coating.
Electrodes with rutile or cellulosic coating require some moisture in
the coating to operate properly and should not be re-dried. If rutile
electrodes get wet, re-drying at about 80°C is all that is needed.
Cellulosic electrodes must not be dried. In some hot environments
they may need wetting to function efficiently.
Basic coated electrodes need to be dry to give low-hydrogen weld
metal. Before use, these electrodes should be re-dried according
to manufacturers’ recommendations, put in holding ovens and
then transferred to the workstations in heated quivers until
needed. Vacuum-packed basic electrodes can be used straight from
the packet.
Electrodes for non-ferrous alloys and stainless steel always need to
be completely dry before use and should be treated in accordance
with manufacturers’ requirements.
Welding Parameters
Some electrodes will operate satisfactorily on AC or DC current
and, for AC operation, manufacturers will recommend a minimum
OCV (Open Circuit Voltage) to initiate a welding arc with
the electrode.
Care and Conditioning of Consumables