Welding textbook CH 6

The approximate temperature of an SMAW arc is _______°F (3600–3900°C).

• 6500–7000

• 10,000–10,500

• 5600–6300

• 7600–8500

Which of the following is not a type of DC welding machine?

• Motor or engine-driven DC generator

• Motor or engine-driven DC generator with an AC rectifier

• An AC transformer with a DC rectifier

• Motor or engine-driven generator with a DC rectifier

The average no-load voltage in a DC arc welding circuit is _______ volts.

• 10–20

• 15–30

• 60–80

• 15–40

What may be the result if a person receives an arc flash?

• The person may be temporarily blinded

• The person may see white spots for a time

• Permanent damage to the retina may occur

• All the above are possible

The weave bead width should be _______ the diameter of the electrode being used.

• the same as

• no wider than 2–3 times

• no wider than 4 times

• no wider than 6 times

A whipping motion is used to _______.

• produce a thinner weld bead

• allow the weld time to cool

• allow time for the flux to reduce the oxides

• allow time for the flux to clean the metal surface ahead of the arc

Where should a weld be restarted on a previously unfinished bead?

• At the leading edge of the previous bead

• In the middle of the previous bead crater

• At the trailing edge of the previous bead

• At any point on the bead

Undercut in a horizontal inside corner joint usually is a(n) ____.

• depression in the lower piece

• depression along the upper edge of the weld on the vertical piece

• depression along the outer edge of the horizontal piece

• overhang of metal at the toe of the weld

As a weld nears the end of the joint, a DC arc has a tendency to blow ____.

• toward the end of the joint

• toward the beginning of the joint

• to the right side of the joint

• to the left side of the joint

Gravity causes the metal in the arc to fall as it travels across the arc. What can be done to minimize this effect while welding in the horizontal, vertical, or overhead positions?

• Decrease the arc gap slightly.

• Increase the arc gap slightly.

• Increase the amperage slightly.

• Increase the welding speed.