COMPLETE 90 QUESTIONS AND CORRECT DETAILED
ANSWERS
What is the term used to describe the following condition of lost corrosion
resistance?
"When certain stainless steels are heated between 500-850° C, carbides form at the
grain boundaries and cause a local depletion of chromium."
(A) Oxidization
(B) Increased toughness
(C) Solution heat treatment
(D) Sensitization - ANSWER: (D) Sensitization
Note: Also known as "carbide precipitation" -- Chromium binds to carbides, and
"sweats out" at the grain boundaries
On a radiograph, undercut appears as a _________ line.
(A) light
(B) dark - ANSWER: (B) dark
What is the Canadian Standard for safety in welding? - ANSWER: CSA W117.2
What is the typical three-phase input voltage in most Canadian welding shops? -
ANSWER: 600V
True or False: The cable from the workpiece back to the welding machine is called
the "ground lead". - ANSWER: False. The correct term is the "work lead".
What is the type of radiation that can damage living cells? - ANSWER: Ionizing
Name two examples of ionizing radiation. - ANSWER: X-rays and Gamma rays
What is the minimum suggested shade for a welding helmet when using 5/32 SMAW
electrode at 150 A? - ANSWER: Shade 10
Approx. how far could spatter travel when welding/cutting from 2.5m high? -
ANSWER: Possibly up to 6m
What is the toxic component contained in some copper alloys? - ANSWER: Beryllium
Which welding process will likely have the highest fume generation rate?
[SMAW / SAW / FCAW] - ANSWER: FCAW
,What do the terms TLV and TWA stand for? - ANSWER: TLV: Threshold limit value
TWA: Time weighted average
The action of UV light on oxygen produces which toxic gas? - ANSWER: Ozone
Which common fuel gas has the widest range where it can become flammable when
mixed with air? - ANSWER: Acetylene
What substance should you NEVER apply to a stiff pressure-adjusting screw on an
oxygen regulator? - ANSWER: Oil or grease
What is the maximum gauge pressure that acetylene should be used? (kPa/psi) -
ANSWER: 103 kPa (15 psi)
Which toxic gas is produced when welding on surfaces with chlorinated hydrocarbon
solvents? - ANSWER: Phosgene gas
What is the typical max. OCV of an AC welding machine? - ANSWER: 80 V
In an isometric drawing, the lines (for width, length and depth) are inclined at an
angle of how many degrees? - ANSWER: 30°
What are the maximum number of views in an orthographic drawing? - ANSWER: 6
What are the two general classes of picture drawings? - ANSWER: Perspective and
Isometric
What are the 5 basic joints? - ANSWER: 1) Butt
2) Corner
3) T
4) Lap
5) Edge
What are the 5 basic weld types? - ANSWER: 1) Groove
2) Fillet
3) Plug/Slot
4) Surfacing
5) Edge
Plasma cutting torch temp can reach temperatures of __________ ° Celsius. -
ANSWER: 30,000
True or False: All plasma arc cutting equipment is operated using DCEN. - ANSWER:
True
,True or False: Stainless steel can be readily cut with a normal oxy-fuel gas process. -
ANSWER: False
What are the two basic methods of plasma torch operation? - ANSWER: Transferred
and Non-Transferred arc
In North America, the 3 othographic views most commonly-used are: TOP, FRONT
and __________ Side.
[RIGHT / LEFT] - ANSWER: LEFT
What is the difference between a "weld symbol" and a "welding symbol"? -
ANSWER: A "weld symbol" indicates the specific kind of weld to be used (ex. fillet),
and is contained inside of "welding symbol".
In a welding symbol, is the size of the weld located to the LEFT or RIGHT of the fillet
weld symbol? - ANSWER: LEFT
In a welding symbol, is the length of the weld located to the LEFT or RIGHT of the
fillet weld symbol? - ANSWER: RIGHT
In what direction do the electrons flow in an electrical arc?
(A) anode --> cathode
(B) cathode --> anode - ANSWER: (B) cathode --> anode
In arc welding, the arc temperature can exceed temperatures of __________ °
Celsius? - ANSWER: 30,000
Which welding process has the highest arc efficiency? - ANSWER: SAW
Arc voltage __________ when arc length is increased.
[Increased / Decreased] - ANSWER: Increases
In GTAW, what type of penetration and weld width can be expected when using
DCEP? - ANSWER: Shallow penetration, and wide weld
Which polarity is most often chosen for direct current GTAW welding of steels and
why? - ANSWER: DCEN. More heat concentrated at the workpiece --> deeper
penetration
Does SMAW use CC or CV? - ANSWER: CC
For out-of-position welding, would you select a small or large diameter electrode? -
ANSWER: A small diameter electrode
, Does GMAW use CC or CV? - ANSWER: CV
What happens to the SAW weld when you switch from DCEP to DCEN? - ANSWER:
Increased deposition rate, but less penetration
What is the temperature for storing low-hydrogen electrodes? - ANSWER: 120°
Celsius
When using a consumable electrode in DCEN, the majority of the heat is
concentrated on the __________.
(A) Electrode
(B) Workpiece - ANSWER: (A) Electrode
When using a non-consumable electrode in DCEN, the majority of the heat is
concentrated on the __________.
(A) Electrode
(B) Workpiece - ANSWER: (B) Workpiece
Which has a "drooping" curve characteristic - CC or CV? - ANSWER: CC
AC transformer welding power sources use a:
(A) step-up transformer
(B) step-down transformer - ANSWER: (B) Step-down transformer
What is a diode used for in a welding machine?
(A) To produce AC current
(B) To produce DC current - ANSWER: (B) To produce DC current
The typical duty cycle for a Class 1 industrial welding power source is:
(A) 20%
(B) 35%
(C) 60%
(D) 150% - ANSWER: (C) 60%
What current/polarity is used when welding aluminum with GTAW?
(A) DCEN
(B) DCEP
(C) AC - ANSWER: (C) AC
True or False: a welding cable size designation "No. 4" is larger than a "No. 2". -
ANSWER: False.