GALA PULSE SYNERGIC DR ADVANCED. Instructions Manual
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6. MMA PROCESS.
Welding with coated electrode, also known as MMA (Manual Metal Arc), SMAW or 111 process, forms part of the
welding processes by electric arc. Therefore, before starting the requested welding jobs, we must bear in mind the
basic principles of the process.
Electric arc welding with coated electrode is a process whereby the
metal between the part and a coated metal electrode is melted.
As the electrical current circulates through the electrode, heat
increases at the end of the electrode that produces an arc that
melts the core or rod of the electrode, burning its coating. Thus
obtaining the appropriate atmosphere to transfer the molten metal
from the core of the electrode to the melt bath in the base material.
These drops of molten metal fall coated with molten slag from the melting of the arc coating. The slag floats on the
surface and forms, above the welding bead, a protective layer of cast metal, controlling the bead cooling speed and
avoiding the oxidation of the filler metal.
APPLICATIONS
This welding process is especially recommended for repair and maintenance welding, manufacture and installation
of pipes, as well as outdoor assembly work. Production and repair welding in naval construction, storage tanks,
structures, pressure containers, oil refineries, boilers and any type of piping, are some of its application sectors.
The main characteristics of the process are its simplicity and its low price, making it a practical and excellent
procedure for offshore use or outdoor work.
However, the welding procedure with coated electrode is not suitable for its automation or semi-automation; its
application is essentially manual.
If electrodes are used in less favourable conditions (with humidity, with no preheating, etc.) we can improve the
welding features by adjusting the control parameters in manual process.
6.1. MMA SYSTEM INSTALLATION.
Disconnect the communication and wire feeder cables. Connect the terminals depending on the type of electrode to
be used and install the remote control, if needed, in the TELENET connector.
3 Ph
(Mains)
MMA installation graphic.
6.2. MMA SYSTEM START-UP.
1st) Make sure the mains voltage is 400V/ 440V.
2nd) Connect electrode-holder clamp to polarity recommended by the electrode manufacturer. Normally to positive
pole.
3rd) Connect earth clamp to welding table or piece to be welded. Check the correct connection of welding masses.
4th) Verify that electrodes are dry. If necessary, preheat electrodes for at least one hour with a heater.
5th) Connect the supply cable with the suitable plug to the relevant tap.
Electrode-holder clamp polarity depend on the electrode (consult the characteristics provided by
the manufacturer)
