103 Review Flashcards
Question 1
1/1 point
The recommended fit up for a 3G 10-gauge weld would include: (24)
1/8-inch root spacing
tacks between 1/8-1/4-inch
no high-low
all of the above
all of the above
What is the primary purpose of the shielding gas used for gas metal arc welding? (2)
reduce the carbon content in the weld metal
protect the weld from the atmospheric air
combines with weld metal to improve mechanical properties
increases the heat in the weld puddle to improve fusion
protect the weld from the atmospheric air
What is an advantage of using argon over helium shielding gas for GMAW on aluminum? (5)
* stable arc
* superior cleaning
* arc is easy to start
* all of the above
- all of the above
In the wire classification E491T-6, what does the E stand for? (21)
electrode
electrical
elastic
elongation
electrode
When lap joint surfaces are positioned at a 45-degree angle to the horizontal plane for welding, it would be referred to as: (12)
4F
3F
2F
1F
1F
What does the 6 define, in the wire classification E491T-6? (21)|
60,000 pounds minimum tensile strength
slag, current, polarity and shielding gas
the type of shielding gas used
chemistry and properties
slag, current, polarity and shielding gas
The bevel angle normally used on pipe is: (3)|
* 10 degrees to 30 degrees
* 30 degrees to 37.5 degrees
* 40 degrees to 60 degrees
* 60 degrees to 75 degrees
- 30 degrees to 37.5 degrees
What is another name for globular transfer, when using carbon dioxide as a shielding gas? (9)
open arc
Co2 arc
closed arc
extension arc
open arc
What daily shutdown procedures must be followed? (11)
turn off power switch and shielding gas supply valve
disconnect the power to the machine
remove flowmeter/regulators
disconnect the welding gun
turn off power switch and shielding gas supply valve
Which electrode wire is the most versatile and popular for welding carbon steel? (12)
ER70S-4
ERZ0S-5
ER70S-6
ER70S-7
ER705-6
The method of manufacturing fluxes is classified by two categories. Choose the correct answer. (28)
fused and unfused
fused and bonded
oxidized and de-oxidized
granular and paste
fused and bonded
Which of the following may be responsible for excessive internal reinforcement after welding a 1GR carbon steel root? (35)
rotation of pipe too quick
no internal gas purge
drag technique
weld metal applied in the twelve o’clock position
weld metal applied in the twelve o’clock position
Weld bead cracking could be the result of: (30)
*using a short stick out
* using 25 shielding gas on carbon steel
* an overheated welding gun
* rigidly fixed joints
- rigidly fixed joints
Why might a flux hopper be heated? (31)
to ensure the flux remains dry
to improve welding efficiency
to preheat the flux prior to welding
to maintain fusion properties of the flux
to ensure the flux remains dry
Which three dimensions are significant to pipe size: (2)
length, weight, inside diameter
length, wall thickness, schedule
nominal size, length, schedule +
schedule, outside diameter, inside diameter
schedule, outside diameter, inside diameter
Which gas has the highest weight (specific gravity)? (4)
hydrogen
helium
argon
nitrogen
argon
Which statement is correct when referring to galvanic corrosion? (6)
any process that increases the refractory oxide causes corrosion
aluminum subjected to high temperature service
aluminum that is continually subject to oil based environments
steel contacting aluminum, while in a moist environment
steel contacting aluminum, while in a moist environment
Room temperature or preheat of up to alloys. (10)
66 degrees C (150 degrees F)
177 degrees C (350 degrees F)
232 degrees C (450 degrees F)
260 degrees C (500 degrees F)
66 degrees C (150 degrees F)
Pipe size is referred to by the term: (2)
* numerical pipe size (NPS)
* normal pipe size (NPS)
* national pipe size (NPS)
* nominal pipe size (NPS)
- nominal pipe size (NPS)
The proper power source set up for GMAW on aluminum is: (8)
AC with high frequency
DC with straight polarity
DC with reverse polarity
all of the above
DC with reverse polarity
What is the recommended procedure used to reduce distortion, when welding in the 2G position? (21)
place a 1/2-inch root tack in the joint
preset the joint 3 - 4 degrees
reduce the number of passes in the joint
preheat the joint before welding
preset the joint 3 - 4 degrees
What is the recommended electrode stick out for wire diameter 0.035 - 1/16-inch using the FCAW process?
- 1/8-inch - 1/4-inch
- 3/8-inch to 3/4-inch
- 5/8-inch - 1-inch
- stick out is automatically regulated
- 3/8-inch to 3/4-inch
Which of the following aluminum filler metals is suitable for high temperature service? (33)
4043
5356
5554
6061
5554
The primary functions of the flux in the core of the wire are to: (20)
provide deoxidizers
remove impurities
act as an arc stabilizer
all of the above
all of the above
Changing the GMAW gun inclination will: (17)
* change the depth of penetration
* have no effect on the weld
*cause the wire to pile up at the drive rolls
*cause the wire to feed unevenly
- change the depth of penetration
The FCAW process can be used without the addition of externally applied shielding gas for field applications: (17)
when working indoors with little air movement
when welding mild steel with less than 0.35% carbon content
when welding on high manganese crusher rolls
when using a self-shielded tubular flux filled electrode
when using a self-shielded tubular flux filled electrode
What type of hose should be used with helium shielding gas? (31)
* plastic type hoses
* rubber type hoses
* acetylene hose
* oxygen hose
- plastic type hoses
When using carbon dioxide shielding gas with GMAW welding, the mode of metal transfer is: (8)
* spray transfer
* globular and plasma
* short circuit and globular
* pulsed current
- short circuit and globular
The main advantage of SAW over the SMAW process is: (36)
it will not produce X-ray quality welds
it is an expensive way to get high quality welds
SAW requires highly trained operators
high welding speeds and multiple wire-set-up are achieved
high welding speeds and multiple wire-set-up are achieved
GMAW of aluminum is recommended on material: (2)
* less than 3.2 mm (1/8 in.)
* 3.2 mm (1/8 in.) or thicker
* only 12.7 mm (1/2 in.) or thicker
* all of the above
- 3.2 mm (1/8 in.) or thicker
When setting up shop welding assignments, variables change with each project. Which of the following is an essential variable to make sure the final weld has met the standards? (lab)
check and adjust the drive roll tension
clean and feather the tacks
turn on the shielding gas supply
check and adjust the parameters to the welding procedure
check and adjust the parameters to the welding procedure
Which alloys exist in an ER5356 filler wire used in the GMAW process? (17)
aluminum and manganese
aluminum and copper
aluminum and magnesium
aluminum and silicon
aluminum and magnesium
When performing a 2F weld with GMAW on 10mm (3/8-inch) material the electrode angle must remain the same for all three passes. (14)
True
False
False
What is the recommended electrode inclination for a root on a 2F lap joint using 0.045 wire with flux core? (13)
15 degrees - 30 degrees backhand
15 degrees - 30 degrees forehand
0 degrees - 20 degrees backhand
0 degrees - 20 degrees forehand
15 degrees - 30 degrees backhand
In the wire classification E491T-6, what does the 49 define? (21)
49,000 psi minimum tensile strength
minimum tensile strength measured with MPa
maximum tensile strength measured with MPa
49 percent elongation
minimum tensile strength measured with MPa
A 2G with backing, performed with the FCAW process requires the welding technique to be completed:
(37)
with weave beads
with stringers or weave bead
using all stringers
to the discretion of the welder
using all stringers
What are the most common tools for preparing a uniform, accurate land on a piece of pipe? (4)
buffers and files
grinders and files
cone stone and files
grinder and hacksaw
grinders and files
A very small percentage of oxygen mixed with argon will: (9) |
*reduce the cost of shielding gas
* increase puddle fluidity
* create a toxic gas
* oxidize the puddle
- increase puddle fluidity
Which element combined with powdered aluminum, creates a chemical reaction that generates heat used for rocket propellants. (2)
Magnesium
Iron
Oxygen
Hydrogen
Oxygen
When welding with GMAW, use a travel speed that will maintain the wire: (16)
* at the back of the puddle
*at the middle of the puddle
*at the leading edge of the puddle
*at a minimum of 6 mm (1/4 in.) in front of puddle
*at the leading edge of the puddle
When there is a buildup of frost on the carbon dioxide flowmeter, it is recommended that you: (23)
* install a line heater
* increase the gas flow
* increase the inductance
* increase the amperage
- install a line heater
Which of the following would represent the recommended position of a flowmeter? (4)
horizontal to the cylinder
vertical to the cylinder
45 degrees to the cylinder
30 degrees to the cylinder
vertical to the cylinder
Aluminum is used in many applications because of its; (2)
high strength to weight ratio
corrosion resistance
finishing options
all of the above
all of the above
When welding stainless steel, 1% to 9% oxygen is added to argon shielding gas to: (9)
reduce spatter
increase deposition rates
improve the puddle’s wetting action
reduce cost
improve the puddle’s wetting action
A record of a test specimen using variables listed in a WPS that has been thoroughly tested to ensure welders consistently yield good welds is referred to as: (22)
PQR
AWS
CWB
MSDS
PQR
Electrode angle for GMAW on aluminum is: (11)
* 1/4 the included joint angle
* 1/2 the included joint angle
* 0 degrees to 30 degrees forehand
* 0 degrees to 30 degrees backhand
- 1/2 the included joint angle
The 70 in the filler metal designation ER70S-2 refers to: (10)
the percentage of elongation or stretch
minimum of 70 000 psi tensile strength
70 kg spools of filler wire
maximum tensile strength 70 000 MPa
minimum of 70 000 psi tensile strength
When feathering a tack, it is important to also remove metal from the root face (7)
T/F
False
What method is used to provide shielding from the atmosphere when performing the SAW process? (2)
a flux filled wire
an externally applied gas
a granular flux around the arc
flux coating on the wire provides shielding
a granular flux around the arc
Which standard outlines welding parameter ranges for GMAW and FCAW filler wires? (3)
* CSA standard W47-1
* CSA standard W48-14
* CSA standard W49-15
* CSA standard W59.2
- CSA standard W48-14
Which of the following gas blends will reduce high crowned weld beads on stainless steels? (13)
* helium-carbon dioxide
* argon-carbon dioxide
* nitrogen-carbon dioxide
* helium-argon-carbon dioxide
- helium-argon-carbon dioxide
When referencing SAW flux and wire combination F49P2-EH12K, the K indicates: (25)
* multi-pass welds
* killed steel
* contains molybdenum
* magnesium used as a deoxidizer
- killed steel
Which of the following GMAW aluminum filler metals are most common? (5)
4043
5156
4047
5056
4043
What is a disadvantage of using helium over argon shielding gas for GMAW on aluminum? (5)
narrow root width
poor arc initiation
decreased penetration
all of the above
poor arc initiation
Weld progression for the 5G pipe exercise using GMAW is: (27)
root, fill and cap pass uphill
root, fill and cap pass downhill O
root and fill downhill, cap pass uphill
root downhill, fill and cap pass uphill
root downhill, fill and cap pass uphill
The finishing pass of a 3G groove weld shall provide reinforcement at the center of the weld not exceeding: (14)
2.5mm - (3/32-inch)
3.2mm - (1/8-inch)
6.4mm - (1/4-inch)
4.2mm - (5/32-inch)
3.2mm - (1/8-inch)
What is the name for a welding process that uses solid continuous wire and an inert or active shielding gas?
* tungsten inert gas
* shielded metal arc welding
* gas metal arc welding
* flux cored arc welding
- gas metal arc welding
When choosing SAW consumables: (27)
* the flux must be balanced with the chemical composition of the electrode
* the required mechanical properties must be obtainable
* the flux must meet the criteria for additional alloys
* all of the above
- all of the above
Which of the following is an advantage of using the GMAW process for aluminum? (2)
no flux or slag
welds can be completed in all positions
produces higher deposition rates compared to GTAW
all of the above
all of the above
What is the minimum number of tacks required on NPS 4-inch or smaller pipe? (6)
- 2 tacks
- 3 tacks
- 4 tacks
- 5 tacks
- 3 tacks
What is the common method of adjusting the contact tube for short-circuiting metal transfer? (18)
so, it extends slightly beyond the end of the nozzle
so, it is recessed in the nozzle
3/8-inch electrode extension
all of the above
so, it extends slightly beyond the end of the nozzle
Which of the following circumstances would cause turbulence in the flow rate of GMAW shielding gases?
- high voltage settings
- spray arc mode of metal transfer
- shielding gas flow rate that is set to high
- a long electrode extension
- shielding gas flow rate that is set to high
When performing the GMAW process using an inert gas, we could refer to the process as: (4)
* MIG welding
* MAG welding
* self-shielding process
* shielded metal arc welding
- MIG welding
When selecting a power source for SAW you should consider which factors? (9)
* cost and efficiency
* color and size
* brand name and service provider
* rated amperage, duty cycle, input power
- rated amperage, duty cycle, input power
What is the recommended electrode angle for GMAW fillet welds? (16)
* 1/4 of the included angle
* 1/2 of the included angle
* 3/4 of the included angle
* the same as the inclination
- 1/2 of the included angle
When welding the root pass in the 1GR position, what could likely occur in the twelve o’clock position. (14)
* concave root
* root suck back
* excessive penetration
* incomplete penetration
- excessive penetration
Short-circuit or spray transfer may be used when welding aluminum with the GMAW process. (9)
T/F
True
Why is a wire straightener required with SAW wire-feeders? (10)
* to work harden the wire prior to welding, increasing mechanical properties
* to reduce cast, and improve arc stability
* to improve electrical conductivity
* to reduce the effects of arc blow
- to reduce cast, and improve arc stability
Which of the following GMAW modes would produce the most spatter? (9)
* globular transfer with carbon dioxide
* short circuiting transfer, with argon/carbon dioxide
* spray transfer
* spray transfer, argon/carbon dioxide
- globular transfer with carbon dioxide
What type of wire brush do you use to remove oxide film on aluminium before welding?(8)
* carbon steel
* copper
* stainless steel
* aluminum
- stainless steel
What is the cause of lack of fusion with GMAW short-circuiting metal transfer? (26)
* too slow travel speed resulting in a pillowing effect
* too large of a root opening
* too large of a root face
* too small of a root face
- too slow travel speed resulting in a pillowing effect
When performing SAW with an active or alloy flux, why must the arc voltage be closely monitored and controlled? (29)
* to eliminate preheat
* to control the travel speed
* to reduce the affects of arc blow
* to maintain the desired weld metal composition
- to maintain the desired weld metal composition
Self-shielded FCAW is a good choice for welding outdoors because: (17)
* they reduce dimensional defects
* of the portability
* humidity does does not affect the wire
* it tolerates windy conditions
*it tolerates windy conditions
The acronym SAW stands for: (2)
* Straight Arc Welding
* Submerged Arc Welding
* Swift Arc Welding
* Standard Arc Welding
- Submerged Arc Welding
What is the main factor when selecting a filler wire used with the GMAW? (6)
* the type of deoxidizers used
* the correct cast
* current carrying capacity
* match base metal chemistry
- match base metal chemistry
Which of the following is a priority procedure before starting to weld on base materials? (3)
- preheat all materials before welding
- match the wire to the chemical and mechanical properties of the material
- material heat numbers must match filler wire heat numbers
- adjust voltage and current settings for the material thickness
- match the wire to the chemical and mechanical properties of the material
What is the most used regulator/flowmeter for shielding gas? (28)
* floating ball type
* dual gauge type
* regulator type
* two stage type
- floating ball type
The term schedule of pipe is used to reference: (3)
- the percentage of carbon in the pipe
- the recommended service intended for the pipe
- the length of pipe with reference to its wall thickness
- the weight of pipe with reference to its wall thickness
- the weight of pipe with reference to its wall thickness
The wall thickness of standard-weight pipe is equal to: (3)
* schedule 20 from 1/2-inch to 10-inch NPS
* schedule 30 from 1/2-inch to 10-inch NPS
* schedule 40 from 1/2-inch to 10-inch NPS
* schedule 80 from 1/2-inch to 8-inch NPS
- schedule 40 from 1/2-inch to 10-inch NPS
High wire resistance in the liner and contact tip is likely to cause: (22)
* porosity in the weld
* nesting at the drive rolls
* excessive undercut
* damage to the liner
- nesting at the drive rolls
Which filler wire is used with the FCAW process? (23)
* E70T-1
* ER7OU-1
* ER7OS-2
* E70S-1
- E70T-1
According to the AWS flux and wire classification F7A3-EL12K what does the 12 define? (25)
* 12 percent carbon content of the wire
* 1.2 percent carbon content of the wire
* 0.12 percent carbon content of the wire
* 0.012 percent carbon content of the wire
- 0.12 percent carbon content of the wire
Which of the following aluminum filler metals is used to weld 6061 base metal alloys? (33)
4043
4047
5856
5053
4043
Final oxide removal of the weld area takes place by: (7)
* using a file
*using solvents
* using a wire brush
* the welding arc
- the welding arc
When using SAW, the welding head assembly requires which components to function? (5)
filler wire, wire feed motor, feed roll, wire straightener, torch
feed rolls, flux recovery, and power source
power source, contact tip, and spooled wire
wire feed rolls, gas flowmeter, and a nozzle
filler wire, wire feed motor, feed roll, wire straightener, torch
What degree of preset is recommended for a 2G welded with GMAW and MCAW? (20)
* 1 to 2 degrees
* 2 to 3 degrees
* 3 to 4 degrees
* 4 to 5 degrees
- 3 to 4 degrees
The use of backhand inclination is avoided when using GMAW on aluminum: (11)
* because it causes porosity
* because it produces shallow penetration
* because slag could become trapped in the weld
* because a black soot oxide appears on the surface of the weld
- because a black soot oxide appears on the surface of the weld
Wire brushes used for cleaning aluminum, prior to welding should be: (5)
* stainless steel
* low carbon steel
- stainless steel
A general rule of thumb is that all GMAW on aluminum should be done with the uphill progression for best overall results. (22)
T/F
True
What is the recommended technique for a 2G root pass using GMAW short-circuit metal transfer? (21)|
* stringer technique
* weave technique
* sawtooth technique
* drag technique
- sawtooth technique
When using GMAW on aluminum, a longer contact tip produces: (5)
* poor wire feed ability
* less efficient current transfer
* an increased chance of burn-back * more efficient current transfer
- more efficient current transfer
An advantage that FCAW has over GMAW in the welding industry is: (2)
* wire is less expensive
* deposition rates are higher
* less maintenance on equipment
* the volume of shielding gas used is lower
- deposition rates are higher
Shielding gas flow rates are influenced by: (6)
* conduit liner size
* position of the weld
* the polarity used
* the current rating of the gun
- position of the weld
Using the jog button to advance the wire into the gun assembly will: (7)
* automatically adjust the break tension
* purge contaminants in the conduit line
* save shielding gas
* prevent the wire from unravelling
- save shielding gas
When referencing the wire classification number E491T-6, what does the 1 define? (21)
* weld metal chemistry and properties
* 100,000 pounds minimum tensile strength
* welded in all positions
* welded in the flat position
- welded in all positions
A light preheat is beneficial prior to welding aluminum: (10)
* to ensure a hard HAZ
* to ensure a ductile HAZ
* to ensure moisture is eliminated
* to speed up the quench rate of HAZ
- to ensure moisture is eliminated
The main benefit of using FCAW or MCAW over GMAW is: (2)
* less fumes are emitted
* less training is required
* more productivity is achieved
* costs are considerably lower
- more productivity is achieved
A 3F lap joint, done on 3/8-inch thick plates, welded with the MCAW process could be completed with how many passes when using the triangular welding technique? (27)
1 pass
2 passes
3 passes
4 passes
1 pass
When performing SAW, excessive wire speed, arc voltage set to low, or insufficient flux coverage could:
(33)
* cause stubbing
* cause burn-back
* require an increased travel speed to compensate
* require special wire to reduce the effects of these deficiencies
- cause stubbing
The gas metal arc welding process is sometimes called:
A) MIG welding
B) flux cored welding
C) self-shielding process
D) shielded metal arc welding
C) self-shielding process
Which welding process is not classified as a continuous wire feed system?
A) GMAW
B) SMAW
C) FCAW
D) SAW
A) GMAW
The name for an arc welding process that uses a solid continuous wire and an inert shielding gas is:
A) tungsten inert gas
B) shielded metal arc welding
C) gas metal arc welding
D) flux cored arc welding
GMAW welding does NOT:
A) require the use of a shielding gas
B) reduce clean up cost
C) have a fast metal deposit
D) use a flux around the electrode
GMAW CANNOT be used on:
A) aluminum and magnesium
B) mild steel and stainless steel
C) stainless, carbon and low alloy steels
D) zinc diecast
D) zinc diecast
One disadvantage of GMAW iS:
A) equipment is inexpensive
B) the equipment requires more maintenance
C) thin metal may be welded
D) an operator can learn to MIG weld more quickly
B) the equipment requires more maintenance
FCAW uses two variations in the process. What are they?
A) self shielded and gas shielded
B) short circuit and globular
C) globular and spray
D) buried arc and spray
A) self shielded and gas shielded
Under what conditions can the FCAW process be used without the addition of externally applied shielding gas?
A) while working indoors with little air movement
B) on mild steels with less than 0.35% carbon content
C) when welding on high manganese crusher rolls
D) when using a self shielded tubular flux filled electrode
D) when using a self shielded tubular flux filled electrode
Which of the listed items is NOT a basic requirement for GMAW?
A) shielding gas
B) wire feeder
C) gun and cable assembly
D) tungsten wire
D) tungsten wire
The type of current used for most GMAW applications is:
A) AC (alternating current)
B) DCRP (direct current - reverse polarity)
C) DCSP (direct current - straight polarity)
D) AC (with high frequency on continuous)
B) DCRP (direct current - reverse polarity)
When a constant current (CC) power source is used for GMAW it should be set:
a) direct current - reverse polarity
b) direct current - straight polarity
c) alternating current - either polarity
d) alternating current - no fixed polarity
a) direct current - reverse polarity
The polarity used for most applications in the GMAW process is:
a) DC reverse
b) DC straight
c) AC straight
d) AC reverse
a) DC reverse
The FCAW flowmeter is designed to measure:
A) pressure of the gas
B) speed of the gas
C) temperature of the gas
D) volume of the gas being used
D) volume of the gas being used
Short circuiting mode of metal transfer requires a:
a) CC machine and high voltage settings
b) CV machine and small diameter wires
c) CP machine and high voltage settings
d) AC machine and large diameter wires
b) CV machine and small diameter wires
What is an advantage of GMAW, when compared to SMAW?
A) it takes less experience to set up the machine
B) there is less electrode waste
C) the weld can be done outdoors
D) large diameter rods can be used
B) there is less electrode waste
As compared to SMAW, GMAW can increase:
A) cost
B) work
C) safety
D) productivity
D) productivity
One disadvantage of GMAW is:
A) equipment is inexpensive
B) welds are more prone to lack of fusion
C) thin metal may be welded
D) an operator can learn to MIG weld more quickly
B) welds are more prone to lack of fusion
Which power source and feeder combination would be recommended for gas-shielded FCAW?
A) constant current and arc voltage sensing control
B) constant potential and voltage sensing feeder
C) constant current and constant speed control
D) constant potential and constant speed feeder
D) constant potential and constant speed feeder
Which power source is most commonly used for self-shielding flux core arc welding?
A) constant current and arc voltage sensing control
B) constant potential and voltage sensing control
C) constant voltage and constant wire speed control
D) constant current and amperage control
A) constant current and arc voltage sensing control
The amperage is set on a constant voltage (CV) welding machine while using FCAW:
A) with the wire speed control
B) with the dial on the welding machine
C) with the stick out length
D) with the contact tube
A) with the wire speed control
What is considered FCAW’s main advantage(s)?
A) its lack of shielding gas requirements with all wires
B) its high deposition rate
C) it has less complicated equipment than SMAW
D) all of the above
B) its high deposition rate
A disadvantage of FCAW is
A) equip is cheap and easy to set up and maintain
B) it can generate large amounts of smoke
C) there is no slag to remove
it can be run at a great distance from the wire feeder
B) it can generate large amounts of smoke
Why might you choose FCAW over other welding processes?
A) good weld appearance
B) high quality weld deposits
C) resistance to underbead cracking
D) all of the above
D) all of the above
List why you would NOT use FCAW processe(s)
A) slag removal is required
B) equipment is more costly than for SMAW
B) limited to welding ferrous metals and nickel based aloys
D) all of the above
D) all of the above
Constant voltage (CV) machines produce a:
a) drooping volt-amp curve
b) rising volt-amp curve
c) relatively flat volt-amp curve
d) constantly changing volt-amp curve
c) relatively flat volt-amp curve
The power source least suited for the short circuit method of welding is a:
a) CV machine
b) AC machine
c) CC machine
d) An inverter
b) AC machine
The power source best suited for the short circuit method of welding is a:
a) rising voltage power source
b) constant voltage power source
c) constant current power source
d) constant amperage power source
b) constant voltage power source
Which current type is generally used with the GMAW process?
a) DCEN
b) ACHF
c) DCSP
d) DCEP
d) DCEP
A constant potential power source can also be referred to as a:
a) constant voltage machine
b) constant amperage machine
c) constant current machine
d) constant resistance machine
a) constant voltage machine
From these power sources, select the one recommended for GMAW:
a) AC
b) DC constant current
c) AC reverse polarity
d) DC constant voltage
d) DC constant voltage
What type of power source would be best suited for GMAW welding?
a) constant current machines
b) motor generator machines
c) constant voltage machines
d) ac/dc transformer rectifier machines
c) constant voltage machines
In applications where gas metal arc processes are the only processes used, the power source type should be:
a) conventional AC
b) constant potential
c) conventional CC
d) a drooping curve
b) constant potential
The recommended power source and volt-amp curve setting for short circuiting GMAW is:
a) CC moderately drooping
b) CV relatively flat
c) CV relatively steep
d) RAV slightly rising
b) CV relatively flat
What controls amperage in GMAW?
a) voltage
b) diameter of wire
c) watts
d) wire feed speed
d) wire feed speed
A welding machine that produces a relatively flat volt/amp curve is a:
a) constant current machine
b) constant voltage machine
c) rising arc voltage machine
d) high potential welding machine
b) constant voltage machine
Which parameter remains relatively constant while welding with a constant voltage welding machine
A) voltage
B) amperage
C) current
D) resistance
A) voltage
The voltage is set on a constant voltage (CV) welding machine:
A) voltage cannot be set on a CV powere source
B) by changing the length stick out
C) by manipulating the voltage dial on the power source
D) by manipulating the wire feed dial on the power source
C) by manipulating the voltage dial on the power source
A machine with a relatively fat volt amp curve would be best suited for:
a) PAW
b) SMAW
c) GMAW
d) GTAW
c) GMAW
GMAW Welding machines are constucted to specifications set by?
a) AMSE
b) ASTM
c) NEMA
d) FUBAR
c) NEMA
What color and type of clothing is best suited for the GMAW processes?
a) light colored wool shirts and leather gloves
b) light colored long sleeved shirts leather gloves
c) dark colored nylon shirts and leather gloves
d) dark colored long sleeved shirts and leather gloves
d) dark colored long sleeved shirts and leather gloves
High ultraviolet emissions from GMAW will cause oxygen in the air to convert to:
a) ozone
b) carbon monoxide
c) carbon dioxide
d) argon
a) ozone
One reason good ventilation is required for GMAW is to prevent:
a) loss of shielding gas
b) overheating of the weld
c) build-up of metal particles
d) oxygen deficiency
d) oxygen deficiency
A potential source of poisonous chemical exposure in welding is:
a) shielding gases
b) degreasers
c) carbon dioxide extinguishers
d) anti-spatter sprays
b) degreasers
- Water cooled guns are best suited for GMAW when using:
a) low voltage and low amperage
b) high voltage and low amperage
c) low voltage and high amperage
d) high voltage and high amperage
d) high voltage and high amperage
The preferred way of measuring shielding gas flow is:
A) pounds per square inch (kilograms per square centimeter)
B) pounds per hour (kilograms per minute)
C) cubic feet per hour (liters per minute)
D) surface feet per hour (surface meters per minute)
C) cubic feet per hour (liters per minute)
Shielding gas flow is measured in:
A) PSI
B) CFH
C) SFM
D) RPM
B) CFH
The shielding gas flow valve is operated by a:
A) toggle switch
B) solenoid
C) pressure relief valve
D) foot control
B) solenoid
What is a gas solenoid?
A) an impurity in the shielding gas
B) the process for making shielding gas
C) an unused waste gas from the production of shielding gases
D) an electrically operated valve to control shielding gas flow to the weld
D) an electrically operated valve to control shielding gas flow to the weld
The self-shielded flux cored arc welding process might be chosen because it does NOT require
A) a high output welding machine
B) an experienced operator
C) expensive equipment
D) the expense of a shielding gas
D) the expense of a shielding gas
One of the functions of the inner core in gas-shielded FCAW wire is to:
A) provide deoxidizers to the weld
B) lower weld temperature
C) decrease flow rate
D) increase penetration
A) provide deoxidizers to the weld
The preferred way of measuring shielding gas flow is:
A) pounds per square inch (kilograms per square centimeter)
B) pounds per hour (kilograms per minute)
C) cubic feet per hour (liters per minute)
D) surface feet per hour (surface meters per minute)
C) cubic feet per hour (liters per minute)
Inert gas welding flowmeters are calibrated in liters per minute (cubic feet per hour), which measure:
A) volume rate of gas flowing
B) capacity of gas flowing
C) pressure of gas flowing
D) density of gas flowing
A) volume rate of gas flowing
Shielding gas flow is measured in:
A) PSI
B) CFH
C) SFM
D) RPM
B) CFH
The shielding gas flow valve is operated by a:
A) toggle switch
B) solenoid
C) pressure relief valve
D) foot control
B) solenoid
A flow meter is calibrated for:
A) all inert gases
B) fuel or nonfuel gases
C) all gases used for G.M.A.W.
D) a specific type of gas
D) a specific type of gas
Flow meters are calibrated for each type of shielding gas because each gas has a different:
A) ionization potential
B) thermal or electrical conductivity
C) electrical resistance
D) specific gravity or gas density
D) specific gravity or gas density
The approximate range for shielding gas flow, using .035 steel wire and short circuit welding is
A) 4 - 7 L/min (10 - 15) cubic ft./hr.
B) 7 - 23 L/min (15 - 50) cubic ft./hr.
C) 14 - 19 L/min (30 - 40) cubic ft./hr.
D) 24 - 26 L/min (50 - 55) cubic ft./hr.
B) 7 - 23 L/min (15 - 50) cubic ft./hr.
What is the most accurate regulator/flowmeter?
A) floating ball type
B) dual gauge type
C) inverted orifice type
D) the cheapest one available
A) floating ball type
What type of hose should be used with helium shielding gas?
A) plastic type hoses
B) rubber type hoses
C) garden type hoses
D) flexible copper lines
A) plastic type hoses
What is the purpose of the shielding gas in the gas metal arc welding process?
a) reduce the carbon content in the weld metal
b) protect the weld from the atmospheric contaminants
c) combine with the weld metal to increase ductility
d) unite with oxygen which will increase weld properties
b) protect the weld from the atmospheric contaminants
When oxygen and nitrogen become mixed in the molten weld metal, they:
a) strengthen the metal
b) are very harmful to the weld
c) help ductility of the weld zone
d) increase the yield point of the metal
b) are very harmful to the weld
The addition of oxygen to argon will cause temperature of the molten metal to:
a) decrease
b) increase
c) stabilize
d) oxidize
b) increase
When using COshielding gas with GMAW welding, the transfer of the filler metal is by:
a) spray transfer only
b) globular and plasma transfer
c) short circuit and globular transfer only
d) pulsed current and spray transfer
c) short circuit and globular transfer only
What is the main purpose of adding oxygen
(1-9%) to argon when welding mild steel or stainless steel?
a) eliminates porosity
b) gives better penetration
c) allows weld metal to wet out at the toes
d) allows for a greater selection of filler wire to be used
c) allows weld metal to wet out at the toes
Identity the toxic fume created when carbon dioxide is subjected to the heat of the arc in GMAW and FCAW.
a) lead
b) carbon monoxide
c) hydrocarbon
d) argon
b) carbon monoxide
GMAW, with a carbon dioxide shielding gas, requires good ventilation because of emission of:
a) excessive smoke
b) carbon monoxide
c) excessive sparks
d) excessive heat
b) carbon monoxide
The shielding gas most commonly used for GMAW of non-ferrous metals is:
a) carbon dioxide
b) nitrogen
c) helium
d) argon
d) argon
Which shielding gas is used primarily for welding mild steel?
a) carbon dioxide
b) nitrogen
c) helium & argon
d) argon
a) carbon dioxide
If 1% to 9% oxygen is added to the argon shielding gas, it is to:
a) reduce spatter
b) increase deposition rate
c) improve wetting action
d) reduce welding costs
c) improve wetting action
Which of the following gas blends tends to reduce high crowned weld beads on stainless steels?
a) helium-carbon dioxide
b) argon-carbon dioxide
c) nitrogen-carbon dioxide
d) helium-argon-carbon dioxide
d) helium-argon-carbon dioxide
A disadvantage of using carbon dioxide with GMAW is that:
a) porosity may be a problem
b) undercut at the toe of the weld occurs
c) spatter is much more common
d) it is not readily available
c) spatter is much more common
If pure argon is used in the gas metal arc welding process when welding stainless steel, it may cause the weld to have:
a) undercut
b) flat bead contour
c) a vertical interface
d) excess porosity
a) undercut
Helium is used primarily as a shielding gas for which of the following metals?
a) aluminum and copper
b) mild steel and stainless steel c cast iron and cast steel
d) plain carbon steels and low alloy steels
a) aluminum and copper
Argon-oxygen mixtures are common shielding gas for the welding of what type of material?
a) aluminum
b) magnesium
c) copper alloys
d) stainless steels
d) stainless steels
Which of the following GMAW modes would produce the most spatter?
a) globular transfer and carbon dioxide
b) short circuiting transfer and argon carbon dioxide mix
c) spray transfer
d) spray transfer and argon carbon dioxide mix
a) globular transfer and carbon dioxide
With which shielding gas is spray transfer NOT possible?
a) argon-oxygen
b) 10% CO2 argon mix
c) argon
d) carbon dioxide
d) carbon dioxide
Which of the following GMAW shielding gases would require the highest flow rate?
a) argon
b) helium
c) carbon dioxide
d) nitrogen
b) helium - because its lighter than air
Which of the following has the greatest effect on the flow rate of shielding gases?
a) diameter of electrode, wire speed, climatic conditions
b) position of weld, thickness of material, polarity of current
c) type of material, diameter of rod, amount of current
d) type of gas, type of material, position of weld
d) type of gas, type of material, position of weld
- Which gas has the highest weight (specific gravity)?
A) hydrogen
B) helium
C) argon
D) nitrogen
C) argon
The effect of adding small amounts of 02 to argon shielding gas is:
A) it gives less oxidization
B) it gives less porosity
C) it gives the puddle a higher level of viscosity
D) it improves puddle fluidity
D) it improves puddle fluidity
What type of shielding gas is preferred for GMAW short circuit welding of austenitic stainless steels
A) 75% argon, 25% CO2
B) 90% helium, 7.5% argon, 2.5% CO2
C) argon
D) helium
B) 90% helium, 7.5% argon, 2.5% CO2
It is recommended that carbon dioxide cylinders be recharged when the pressure gets below:
a) 175 psi
b) 200 psi
c) 225 psi
d) 250 psi
b) 200 psi
When there is a buildup of frost on the carbon dioxide flowmeter, it is recommended that you should:
A) install a line heater
B) increase the gas flow
C) change the machine setting
D) increase the amperage
A) install a line heater
What shielding gases are generally used with the FCAW process?
A) nitrogen and carbon dioxide
B) argon and nitrogen
C) argon and helium or combinations of these two
D) carbon dioxide and argon or combinations of these two
D) carbon dioxide and argon or combinations of these two
When using FCAW process with an external shielding gas, which gas has the least amount of spatter
A) carbon dioxide
B) argon and carbon dioxide
C) argon and oxygen
D) argon
B) argon and carbon dioxide
When using FCAW, which shielding gas or gas mixture gives a smooth arc, very little spatter and good appearance on plain carbon steel?
A) argon
B) CO2
C) helium
D) 75% argon 25% CO2
D) 75% argon 25% CO2
When FCAW requires an external shielding gas, which shielding gas is most commonly used?
A) carbon dioxide
B) helium and carbon dioxide
C) argon and hydrogen
D) argon
A) carbon dioxide
When FCAW requires an external shielding gas, which gas gives the best penetration and low cost?
A) carbon dioxide
B) argon and helium
C) argon and oxygen
D) argon
A) carbon dioxide
Which shielding gas is most commonly used in flux core arc welding?
A) argon
B) helium
C) CO2
D) 25% nitrogen, 75% argon
C) CO2
Which characteristic best describes CO2 shielding gas with FCAW?
A) good surface cleaning
B) deeper penetration & lower cost
C) broad bent contour
D) smooth arc
B) deeper penetration & lower cost
What shielding gases are generally used with the FCAW process?
A) nitrogen and carbon dioxide
B) argon and nitrogen
C) argon and helium or combinations of these two
D) carbon dioxide and argon or combinations of these two
D) carbon dioxide and argon or combinations of these two
The effect of adding small amounts of 02 to argon shielding gas is:
A) it gives less oxidization
B) it gives less porosity
C) it gives the puddle a higher level of viscosity
D) it improves puddle fluidity
D) it improves puddle fluidity
