CIGWELD 255 - Basic Troubleshooting; Troubleshooting Beyond Welding Terminals; Solving Porosity Problems

TRANSMIG 225, 255 MIG Power Source, 255 2R MIG Wirefeeder
26 Sep 16, 2008
SECTION 14: Basic Troubleshooting
WARNING 11
There are dangerous voltage and power levels present inside this product. Do not attempt to open or repair unless you
are a qualified electrical tradesperson and you have had training in power measurements and troubleshooting
techniques.
If major complex subassemblies are faulty, then the Welding Power Source must be returned to an Accredited CIGWELD Service Agent
for repair.
The basic level of troubleshooting is that which can be performed without special equipment or knowledge and without removing the
covers from the Wirefeeder.
14.01 Solving Problems Beyond the Welding Terminals
The general approach to fix Gas Metal Arc Welding (GMAW) problems is to start at the wire spool then work through to the MIG torch.
There are two main areas where problems occur with GMAW, Porosity and Inconsistent wire feed
14.02 Solving Problems Beyond the Welding Terminals - 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
CAUSE
1
Gas cylinder contents and flow meter.
Ensure that the gas cylinder is not empty and the flow meter is
correctly adjusted to 15 litres per minute.
2
Gas leaks.
Check for gas leaks between the regulator/cylinder connection and
in the gas hose to the Power Source.
3
Internal gas hose in the Power Source.
Ensure the hose from the solenoid valve to the torch adaptor has
not fractured and that it is connected to the torch adaptor.
4
Welding in a windy environment.
Shield the weld area from the wind or increase the gas flow.
5
Welding dirty, oily, painted, oxidised or
greasy plate.
Clean contaminates off the work piece.
6
Distance between the MIG torch nozzle and
the work piece.
Keep the distance between the MIG torch nozzle and the work
piece to a minimum. Refer to section 11.03 on page 21.
7
Maintain the MIG torch in good working
order.
A
B
C
Ensure that the gas holes are not blocked and gas is exiting out of
the torch nozzle.
Do not restrict gas flow by allowing spatter to build up inside the
torch nozzle.
Check that the MIG torch O-rings are not damaged.
CAUTION 5
Disengage the drive roll when testing for gas flow by ear.