Basic Troubleshooting; Solving Problems Beyond The Welding Terminals - Thermal Arc FABRICATOR 251 Operator's Manual

5.02 Basic Troubleshooting

The basic level of troubleshooting is that which can be performed without special equipment or knowledge, and
without removing the covers from the Power Supply.
If major components are faulty, then the Power Supply should be returned to an Accredited Thermal Arc Service Agent
for repair.

5.03 Solving Problems Beyond the Welding Terminals

The general approach to fix GMAW/FCAW problems is to start at the wire spool then work through to the MIG torch.
There are two main areas where problems occur:
Porosity
When there is a gas problem the result is usually porosity within the weld metal. Porosity always stems from
some contaminant within the molten weld pool which is in the process of escaping during solidification of the
molten metal.
Contaminants range from no gas around the welding arc to dirt on the work piece surface. Porosity can be
reduced by checking the following points:
FAULT
Porosity
Manual No. 0-4847
CAUSE
1. Gas cylinder
contents and flow meter
2. Gas leaks
3. Internal gas hose in
the power supply
4. Welding in a windy
environment
5. Welding dirty, oily,
painted, oxidized or
greasy plate.
6. Distance between the
MIG torch nozzle and
the work piece.
7. Maintain the MIG
torch in good working
order.
Table 5-1: Porosity Problems
5-3
REMEDY
a. Ensure that the gas cylinder is not
empty and the flow meter is correctly
adjusted to 25CFM (15 litres per minute)
a. Check for gas leaks between the
reulator/flowmeter connection and in the
gas hose to the power supply
a. The hose from the solenoid valve to
the MIG torch adaptor may be fractured
or disconnected from the MIG torch
adaptor. Return to an Accredited Thermal
Arc Service Agent for repair.
a. Shield the weld area from the wind or
increase the gas flow
a. Clean contaminates off the plate
a. Keep the distance between the MIG
torch nozzle and the work piece to a
minimum.
a. Ensure that the gas holes are not
blocked and gas is exiting out of the
torch nozzle. Refer to WARNING below
b. Do not restrict gas flow by allowing
spatter to build up inside the MIG torch
nozzle.
C. Check that the MIG gun O-rings are
not damaged.
FABRICATOR 251
SERVICE