Deck 31: Oxyfuel Welding Equipment, Setup, and Operation

Question 1

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

Answer 1

B

Question 2

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.

Answer 2

D

Question 3

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.

Answer 3

D

Question 4

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 ° 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 5

____ 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 6

A ____ draws off excessive heat.

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

Question 7

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 8

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 9

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

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

Question 10

The ____ has a right side and a left side.

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

Question 11

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 12

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 ° 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 13

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 14

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

Question 15

During the early ____, the oxyacetylene flame became more popular as the primary means of welding.

A) 1800s
B) 1900s
C) 1980s
D) 2000s

Question 16

The ideal angle for the welding torch is ____.

A) 15 °
B) 30 °
C) 45 °
D) 60 °

Question 17

The rhythm of moving the torch helps ____.

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

Question 18

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 19

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

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

Question 20

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.

Question 21

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

Question 22

The oxygen and ____________________ flame is the only 100% nonpolluting fuel-gas flame.

Question 23

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 24

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 of the torch 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 25

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

A) C₂H₂
B) O₂
C) CO₂
D) NO₂

Question 26

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

Question 27

What is the minimum tensile strength of a class RG65 welding rod?

A) 35,000 to 45,000 psi
B) 45,000 to 55,000 psi
C) 55,000 to 65,000 psi
D) 65,000 to 75,000 psi

Question 28

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 29

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 30

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) It will help minimize distortion.
D) It gives the weld bead a more uniform appearance.

Question 31

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 32

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 33

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

Question 34

____ seal tips must be tightened with a wrench.

A) O-ring
B) Gasket
C) Metal-to-metal
D) Rubber

Question 35

____________________ filler rods for gas welding are small, round, or square iron castings.

Question 36

____________________ filler metals are welding rods that are mainly iron.

Question 37

When mixing oxygen and fuel gas, one method uses equal or balanced pressure and mixes gases in a(n) ____.

A) mixing chamber
B) injector chamber
C) fuel injector
D) injector mixer

Question 38

The injector allows oxygen at the higher pressure to draw the fuel gas into the chamber even when the fuel gas pressure is as low as ____.

A) 6 psig
B) 6 oz/inch²
C) 10 psig
D) 10 oz/inch²

Question 39

____ is the most widely used fuel gas for oxyfuel processes.

A) Oxygen
B) Hydrogen
C) Acetylene
D) Argon

Question 40

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 41

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

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

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

Question 44

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

Question 45

What are the properties of class RG65 welding rods?

Question 46

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

Question 47

Explain how to make a flat butt joint.

Question 48

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

Question 49

A(n) ____________________ torch must be used if a low-pressure acetylene generator or low-pressure residential natural gas is used as a fuel-gas supply.

Question 50

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