MIG welding certification exams are a sort of unusual for structural welding jobs. They’re further typically used for pipe welds.
MIG Weld exams that are given for pipe welder jobs are typically 6-inch schedule 80 pipe welded throughout the 6G place (pipe is positioned at a 45 diploma angle).
This is a fairly frequent test setup:
- 6-inch carbon steel pipe, schedule 80, 37.5 diploma bevel with a 0″ to 1/16″ land. 1/8″ gap.
- E70S6 bare wire with 75/25 argon/CO2 shielding gasoline.
- The premise is welded downhill, and the rest of the passes are welded uphill.
Some MIG welding exams use Flux core combine for the fill passes after the idea is welded with bare wire MIG. E70S6 is used for the idea and E71-T1 is used for the flux core fill passes.
Usually, if the idea goes is downhill, it is an open butt joint with no backing. If backing is used, an uphill root go is widespread.
For open butt root passes, the issue that will kill a test is slipping and capturing wire by way of the once more side. Some test inspectors will fail your test for that…and all it takes is one slip, so being rock common is significant.
A 6G place downhill root goes with no backing requires the welder to repeatedly reposition his physique to maintain up gun angle and to stay throughout the sweet spot of the puddle with out capturing whiskers by way of. Sounds simple, nonetheless under the pressure of realizing paying pipe welding job is in peril, the shakes can take over and destroy your day. That’s the reason it is vital to watch ample so that you just will not be nervous on test day.
- Stick out = the hole between your arc and the contact tip. Maintain it temporary on bare wire combine and longer on flux core
- MIG gun angle. A pipe is spherical. Duh. correct? defending the gun angle acceptable on the 6-inch pipe means altering place simply and sometimes. All the whereas guaranteeing you don’t shoot wire by way of the idea.
- Maintain the nozzle clear. A nozzle full of spatter will lastly temporary out whilst you contact the copper nozzle to the pipe. It on a regular basis happens on the worst time. Clear the nozzle every go.