– 12 –
13
FIG.
(14)
(14.1)
8.8 DIRECTION OF WELD – FIG. 14
Strike the initial arc perpendicular to the parent metal
before moving the electrode holder in the direction of
travel 20-30° (Z,Y axis) and tilt it 20-30° (Z,X axis).
Maintain a constant gap between the electrode tip and
the weld pool of approximately 1 to 1.5 times the
diameter of the electrode for a stable arc. This machine
is equipped with two additional features ‘Arc Force’ and
‘Anti-Stick’ to ensure smooth welding and reduce the
instances of the electrode becoming stuck to the parent
metal.
Z
-Z
-X
-Y
XY
Direction
of weld
14
FIG.
Definition:
ARC FORCE
The machine will automatically create a specific
overpower when the electrode is too near, forcing it back
to help avoid the risk of sticking.
Definition:
ANTI-STICK
The machine will automatically reduce the intensity of
the current in order to aid quick and simple separation of
the electrode and parent metal.
The position of the electrode is critical to the arc and the
end result. Achieving a good weld will take practice.
For more detailed information refer to a welding book
and/or seek training on the subject.
Use of an anti-spatter spray Draper stock No.05709 will
help to achieve a cleaner finished weld. This welding
power source has a maximum material thickness
capability of 5mm.
8.9 THERMAL CUT-OUT
If welding for extended periods the thermal cut-out will
activate prohibiting use of the machine until sufficiently
cool.
Attention: After completion of any welding task leave
the unit connected to the power supply for a sufficient
period to allow the cooling fan to continue working.
8.10 DEFINITION:
DUTY CYCLE:
Duty Cycle is a percentage of 10 mins. in which a
machine can operate at a rated load without overheating
and interruption from the thermal cut-out device.
Example:
150A @ 30% Duty factor
150A welding for 3 minutes
7 minutes down time
Example:
95A @ 100% Duty factor
95A continuous welding
To increase the operation time, reduce the amperage.
Note: The heating tests have been carried out at
ambient temperature and the duty cycle (duty factor) at
20°C has been determined by simulation
Definition:
ARC WELDING:
Fusion welding in which heat for welding is obtained
from an electric arc.
Definition:
MANUAL METAL ARC (MMA welding):
Also known as
SMAW (Shielded metal arc welding).
Metal-arc welding† with straight covered electrodes of a
suitable length and applied by the operator without
automatic or semi-automatic means of replacement. No
protection in the form of gas from a separate source is
applied to the arc or molten pool during welding.
†Arc welding using a consumable electrode.
Definition:
TUNGSTEN INERT-GAS (TIG welding)
Also known as GTAW (Gas tungsten arc welding)
Gas-shielded arc welding using a non-consumable pure
or activated tungsten electrode where the shielding is
provided by a shroud of inert gas.
Note: Although the tungsten electrode is classed as
non-consumable compared to the filler rod type
electrode it will be consumed by the TIG process and
