Deck 32: Oxyacetylene Welding

Question 1

Which of the following is true of the lap joint?

A) The filler rod should be added to the bottom sheet.
B) Heat is not distributed uniformly in the lap joint.
C) If the rod is added directly into the notch, the weld strength will be affected.
D) The flame must be directed at the top sheet and away from the bottom sheet.

Answer 1

B

Question 2

In a vertical weld, the ____ will constantly be solidifying, forming a new shelf to support the molten weld pool.

A) shelf
B) trailing edge
C) leading edge
D) molten weld pool

Answer 2

B

Question 3

The distance between the inner cone and the metal ideally should be ____.

A) 1/16 to 1/8 in.
B) 1/8 to 1/4 in.
C) 1/4 to 3/8 in.
D) 3/8 to 5/8 in.

Answer 3

B

Question 4

A change in the number of sparks given off by the weld as it progresses can be used as an indication of ____.

A) changes in the weld temperature
B) changes in the temperature of the atmosphere
C) changes in the torch angle
D) changes in the flame size

Question 5

The rhythm of moving the torch helps ____.

A) prevent burn-through
B) flashing
C) make the bead uniform
D) protect the molten metal with the outer flame envelope

Question 6

A ____ draws off excessive heat.

A) heat sink
B) filler rod
C) shielding gas
D) weld pool

Question 7

If the molten weld pool size increases beyond that which the ____ will support, the pool will overflow and drip down the weld.

A) core
B) pool
C) edge
D) shelf

Question 8

On thick metal, a ____ diameter filler rod may be used to ____.

A) small, decrease penetration
B) small, increase penetration
C) large, increase penetration
D) large, decrease penetration

Question 9

The ____ has a right and a left side.

A) vertical tee joint
B) flat butt joint
C) vertical lap joint
D) flat lap joint

Question 10

____ of a tee joint enables a larger weld to be made than either the butt or lap joint.

A) Uniformity in the reinforcement
B) Root penetration
C) Surface tension in the molten weld pool
D) Torch angle in the groove

Question 11

The ideal angle for the welding torch is ____.

A) 15°
B) 30°
C) 45°
D) 60°

Question 12

In a horizontal stringer bead, the weld bead will tend to sag downward, and as a result there may be a(n) ____ on the bottom edge.

A) undercut
B) overlap
C) crack
D) wormhole

Question 13

Often the number of sparks in the air increases just before a ____ takes place.

A) backfire
B) weld crater cracking
C) burn-through
D) flashback

Question 14

Some joints, such as the lap joint, may never need 100% ____; however, they do need 100% ____.

A) fusion, penetration
B) penetration, accuracy
C) depth, accuracy
D) penetration, fusion

Question 15

Which of the following is true of mild steel welds?

A) The primary flame shields the molten weld pool.
B) Carbon dioxide that is formed reacts with the molten weld pool.
C) It is possible to make welds with 100% integrity.
D) The carbon dioxide draws the surrounding atmosphere into the weld.

Question 16

Which of the following is true of the flat outside corner joint?

A) It must be made with the addition of filler metal.
B) It is one of the most difficult to make.
C) If the sheets are tacked together properly, filler metal is needed.
D) If filler metal is added, it should be added uniformly.

Question 17

Small molten weld pools are ____ large ones to drip.

A) less likely than
B) as likely as
C) more likely than
D) much more likely than

Question 18

Which of the following is true of the tee joint?

A) The tee joint does not suffer from uneven heating as the lap joint does.
B) The tee joint is easier than the lap joint.
C) The angle of the torch should be away from the direction of weld travel.
D) A large percentage of the welding heat is reflected back on the torch.

Question 19

As the diameter of the filler wire is decreased, the heat absorbing effect ____, and the molten weld pool becomes ____.

A) increases, deeper
B) decreases, wider
C) decreases, deeper
D) increases, shallower

Question 20

Which of the following is true of the vertical weld?

A) It is the most common out-of-position weld.
B) The more vertical the sheet, the easier the weld is to make.
C) Welding on a sheet at a 45 degree angle requires as much skill as a 90 degree angle.
D) The speed of the manipulation is faster when the sheet is at 45 degree angle.

Question 21

​Why should the end of the welding rod be kept inside the protective envelope of the flame?

A) ​To keep the hot end from oxidizing if it is exposed to the air.
B) ​To keep it hot so it will melt into the weld pool faster.
C) ​It is easier to see there, and you are less likely to touch it to your hand, arm, or leg.
D) ​You can add the rod quicker if it is kept close to the weld pool.

Question 22

​Which pipe welding position has the pipe held fixed horizontally?

A) ​1G
B) ​2G
C) ​5G
D) ​6G

Question 23

​What effect on the weld pool would speeding up or slowing down have?

A) ​The weld will move to the right and to the left.
B) ​It has no effect on the weld pool, just on how the filler metal is added.
C) ​It will make the weld pool larger or smaller.
D) ​None of the above

Question 24

Which of the following is true about overhead welding?

A) The height of the sheet does not affect your progress.
B) The direction that you choose to weld is a matter of personal preference.
C) The height of the sheet does not affect your skill.
D) Welders should always stand when welding in the overhead position.

Question 25

​Why would you move the welding hoses before you start welding?

A) ​To make sure it is not too stiff from being cold.
B) ​To eliminate any twisting it may have that could make it harder to manipulate the torch.
C) ​It will give you a sense of how heavy the torch and hose are before you start welding.
D) ​To make sure you have a good grip on the torch.

Question 26

Welding rod size and ____________________ can be used to control the weld bead characteristics.

Question 27

​By controlling the torch flame carefully it is possible to ____________.

A) ​make a weld bead vertically on a horizontal plate.
B) ​make a weld bead horizontally above the horizontal plate.
C) ​accurately control the weld bead in out-of-position welds.
D) ​All of the above

Question 28

Which of the following is true of horizontal welds?

A) The weave pattern required for a horizontal weld is similar to other positions.
B) The sheet should not be tipped back at a 45 degree angle for stringer beads.
C) They must rely on some part of the weld bead to support the molten weld pool.
D) Care must be taken not to allow a shelf to build up under the molten weld pool.

Question 29

Which of the following is true of making a proper stop?

A) You should slightly taper down the molten weld pool by flashing the torch off.
B) Flashing the torch off prevents the molten weld pool from solidifying.
C) If the flame is removed too late from the molten weld pool, it will rapidly oxidize.
D) Pockets of oxides add strength to the weld.

Question 30

____________________ is the depth into the base metal that the weld fusion or melting extends from the surface, excluding any reinforcement.

Question 31

Building up the molten weld pool before it is ended will help prevent crater ____________________.

Question 32

​Which pipe welding position has the pipe held vertically?

A) ​1G
B) ​2G
C) ​5G
D) ​6G

Question 33

​Why would you not reduce the flame size below its correct setting if the torch flame is too large for the job?

A) ​Lowering the flame can result in the tip overheating.
B) ​The flame would go out so you would have to relight the torch.
C) ​Because lowering the gas flow will not reduce the flame heat.
D) ​You would lower the flame so you would not burn through the metal due to the excessively large flame.

Question 34

​What gas from the flame can protect the molten weld metal from oxidizing?

A) ​C2H2
B) ​O2
C) ​CO2
D) ​NO2

Question 35

The ____________________ angle and the angle between the inner cone and the metal have a great effect on the speed of melting and size of the molten weld pool.

Question 36

​What would happen if the secondary flame is suddenly moved away from the molten weld pool?

A) ​The pool will cool off.
B) ​The molten pool will not have any change because it takes a while for it to cool and become solid.
C) ​The torch flame may go out from the sudden movement.
D) ​The molten pool would throw off a large number of sparks.

Question 37

With the ____ weld, the molten weld pool is held to the sheet by surface tension.

A) overhead
B) vertical
C) flat
D) horizontal

Question 38

The ____________________ must be protected by the secondary flame to prevent the atmosphere from contaminating the metal.

Question 39

Which of the following is true of welding mild steel pipe and tubing?

A) They cannot be gas welded.
B) The welding process for pipe and tubing is different.
C) Even thin-walled material requires grooved preparation.
D) Gas welding is seldom used to manufacture piping systems.

Question 40

​Why would you use a back stepping welding technique?

A) ​It is easier to see where you are welding.
B) ​It is easier to make a uniform weld with fewer defects.
C) ​To minimize distortion.
D) ​It gives the weld bead a more uniform appearance.

Question 41

Whenever a weld is performed in a position other than flat, it is said to be ____________________.

Question 42

____________________ the torch off allows the molten weld pool to cool by moving the hotter inner cone away from the molten weld pool itself.

Question 43

In a lap joint, heat is conducted away faster in the ____________________ plate.

Question 44

Describe how the correct diameter of filler metal will help control the weld bead width, buildup, and penetration.

Question 45

Explain how to make a flat butt joint.

Question 46

When welding in the ____________________ position, it is important to wear the proper personal protection, including leather gloves, leather sleeves, a leather apron, and a cap.

Question 47

Suppose you want to practice welding on tubing, but none is available.What can you do?

Question 48

Why should the filler rod be added to the top sheet in a lap joint?

Question 49

Explain how torch angle and the distance between the inner cone and the metal affect the rate of heating.

Question 50

Burn-through does not happen to molten metal until it reaches the ____________________ temperature.