Clarke 195TE, Руководство по эксплуатации и техническому обслуживанию

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PREPARATION FOR WELDING
1. Attach the earth clamp to the bare metal to be welded. Ensure contact is good .
2. Make sure that the wire-roller groove in the roller corresponds to the diameter of the
welding wire being used. Refer to “Loading wire” above.
3. Plug the machine into a 230V AC 50Hz outlet.
4. Open the gas valve on the gas cylinder regulator, (turn knob clockwise)and adjust
the gas regulator to the proper setting position. NOTE: this varies with different metals,
thicknesses and currents. Refer to a MIG welding manual for instructions.
TUNING THE WELDER
The tuning of a Mig welding machine requires some practice, due to the fact that
- contrary to the arc welding procedure - two parameters must be accommodated
to achieve a perfect weld. These are:
(A) Wire Feed Speed, and (B) Welding Voltage.
It is important to arrive at the correct combination to suit the type and thickness of
material to be welded.
The current necessary for welding is directly dependent
upon the wire feed speed.
If the wire feed speed is increased, the current is also increased, but the arc length
is decreased. Conversely, if the wire feed speed is decreased, and current is
therefore decreased, the length of arc is increased.
Increase of the welding voltage leads to a longer arc (without substantially
affecting the current). Conversely, a decreased welding voltage results in a shorter
arc, (the current again is not substantially changed).
A change in wire diameter results in changed parameters. A smaller diameter
wire requires an increase in wire feed speed to reach the same current. If certain
limits are exceeded, a satisfactory weld cannot be obtained. These are:
A) A too high wire feed speed (too high with regard to the welding voltage)
results in pulsing within the torch. This is because the wire electrode dips into
the puddle and cannot be melted off fast enough.
B) If the welding voltage is set too high, large drops can be seen at the end of
the wire electrode. These drops are often deposited beside the welding seam.
The correct rate of wire feed speed (current) and welding voltage, results in very
little spatter and a continuous, intensive hissing can be heard from the arc.
OPERATION
1. These machines have 6 welding positions (see the table below) in which to
regulate current for various conditions.
2. The selection of a welding position is determined by the thicknessof the metal
to be welded. The thicker it is, the higher the current must be.
3. According to the thickness to be welded, the amount of gas regulated to the
work also varies and must be adjusted accordingly.
4. For welding adjustments, refer to the table below.