Exam 18: Gas Tungsten Arc Welding of Pipe

Before the joint is assembled, to remove any sources of contamination, clean a ____ inch wide or wider band, both inside and outside of the pipe.

To purge the air out of a 10 foot section of 6 inch diameter pipe, if the flow rate is 20 cfh, the flow time will be approximately ____.

Define concave root surface and list its common causes and consequences.

The easiest method of protecting the root from atmospheric contamination is to use a(n) ____________________.

In preparing the pipe for welding, the pipe should be tack welded together with a root opening of ____ inch.

​What can be done to prevent the backing gas from being blown through the joint?

Most codes and standards for GTA pipe welding require ____ percent root penetration.

Two of the most common root defects are ____.

After the bevel has been cut, the root face is created by ____.

The end of the pipe is prepared with a bevel, leaving a root face of ____ inch.