5.3 CONNECTOR FOR MIG WELDING
with a Spool or Push-Pull torch
1) Connect the earth cable to the appropriate '-'
socket. (14 of figure 1). Insert by lining up the
key with the groove and turn in a clockwise
direction until it stops. Do not fasten too tightly!
2) Connect the torch to the appropriate socket
on the front of the device (11 of Fig 1), turning
in a clockwise direction until it stops. Do not
fasten too tightly!
3) Insert the connector of the torch into the
appropriate female socket.
In the event the Spool torch is not suitable for
connection with connector 11, making it
therefore impossible to proceed to step 2,
follow these instructions:
1) Connect the earth cable to the appropriate
'-' socket (14 of figure 1). Insert by lining up
the key with the groove and turn in a
clockwise direction until it stops. Do not
fasten too tightly!
2) Connect the torch cable to the '+' socket (15
of figure 1). Insert by lining up the key with the
groove and turn in a clockwise direction until it
stops. Do not fasten too tightly!
3) Insert the gas tube of the torch into socket
12 of figure 1.
4) Insert the torch trigger signal into the
appropriate female socket.
MIG WELDING:
Connect the pressure regulator to the cylin-
der, after which attach the gas tube of the
torch to the latter.
Fig.5
MIG welding
is
usually carried out
with a constant cur-
rent, with a positive
pole ("+ "see fig.5).
The MIG torch cable
is connected to the
Euroconnector (11
of fig.1), whilst the
earth cable of the
workpiece is con-
nected to the '-'
socket on the front
(14 di fig.1).
At this stage adjust the welding current using
the potentiometer (9 of Fig.1), situated on the
front panel.
6. STRIKING AN ARC IN MIG WELDING
The MIG-MAG welding process is when an
electric arc is created between a consuma-
ble wire and the workpiece, protected within
a gas atmosphere. This atmosphere can be
either inert (Argon) or active (CO2 or a mix-
ture of Argon and CO2).
The wire is continuously fed through a torch
by a wire feeder to the weld pool. A solid wire
or flux-cored wire can be used.
The transfer methods of the filler material defi-
ne different arc types:
SHORT ARC (short-circuit transfer):
this brings the electrode into direct contact
with the weld pool, which creates a short-cir-
cuit that extinguishes the arc, after which the
arc reignites and the cycle is repeated.
SPRAY ARC (spray transfer):
this allows the droplets to detach from the tip of
the electrode, which successively reach the
weld pool.
The fact the arc is visible, reduces the need for the
operator to strictly observe the adjustment tables,
allowing for direct control of the welding pool.
- the tension directly influences the appea-
rance of the welding seam, but the dimen-
sions of the welding surface can be varied,
according to requirements, by manual move-
ment of the torch to obtain variable deposits
with a constant tension.
- the speed of the movement of the wire is
in relation to the welding current.
13