Exam 17: Gas Tungsten Arc Welding of Plate

Failure to remove tungsten contamination properly will result in ____________________.

Exceeding the maximum gas flow rates ____.

___________________ is GTA welded using a rounded tip tungsten, with the welding machine set for ACHF welding current.

When setting up to make a GTA weld on low carbon steel, the tungsten should be ________ and the welding machine set for____________.

Explain why the filler rod end must be kept inside the protective zone.

What are the Experiments in this chapter designed to do?

Explain why a few molecules of gas trapped inside microscopic pockets within the steel can cause porosity in GTA welding, but not in other types of welding.

In GTA welding, the torch may be angled ____ for better visibility.

When might the GTAW process be used to make only the root pass on a pipe weld?

Under what conditions is the amperage set on a machine equal to the actual welding current?

With ____, lack of cleanliness may cause the weld pool to show overheating or poor gas coverage.

A ____ degree angle or less to the plate surface prevents air from being pulled into the welding zone behind the rod.

Why would a welder need to make a list of machine settings?

____ is inexpensive and requires the least amount of cleaning.

The ____ possible gas flow rates and the ____ preflow or postflow time can help reduce the cost of welding.

Oxides on ____ may prevent the molten weld pool from flowing together.

Explain how a new student may clean a practice weld of tungsten contamination.

Using a ____ arc current setting with ____ travel speeds is important when welding stainless steel.

Most GTA filler metals have some alloys, called ____________________, that can help prevent porosity caused by gases trapped in the base metal.

As the gas flows out of the torch it must form a(n) ____________________ around the weld.