SMAW EQUIPMENT 120102A Flashcards
1. Define SMAW-related terms. 2. Describe AC and AC-DC rectified welding power sources. 3. Describe AC and DC generator welding power sources. 4. Describe multi-process inverter welding power sources. 5. Identify welding cables and accessories for welding power sources. 6. Identify the effect of arc length on amperage and voltage.
Which term describes the voltage output of the machine while welding is being done?
a) arc rectification
b) arc blow
c) arc voltage
d) inductance
c) arc voltage
When current flows through a coil wrapped around an iron core, what is created?
a) a magnetic field
b) reverse polarity
c) transformer rectifier
d) duty cycle
a) magnetic field
This device in a welding machine is designed to have a certain number of turns of wire.
a) circuit
b) core
c) coil
d) cycle
c) coil
The main function of this device is to change AC to DC.
a) resistor
b) rectifier
c) relay
d) reactor
b) rectifier
Which term describes the NEMA rating of a welding machine?
a) duty cycle
b) direct current
c) arc voltage
d) amperage
a) duty cycle
This term describes the influence exerted by a magnetic field on neighbouring bodies without physical contact.
a) voltage
b) amperage
c) frequency
d) inductance
d) inductance
Electrode negative is:
a) straight polarity.
b) reverse polarity.
c) AC transformer.
d) alternating current.
a) straight polarity.
This term describes a noisy, uncontrollable arc that flares from side to side.
a) arc voltage
b) arc blow
c) inductance
d) resistance
b) arc blow
What term describes a medium that provides an electrical path for current to flow through?
a) cycle
b) circuit
c) conductor
d) core
c) conductor
This is the fundamental unit of electricity and they move through a conductor when current is flowing.
a) resistors
b) electrons
c) conductors
d) rectifiers
b) electrons
This current flows in one direction only and has either a positive or negative value.
a) direct current
b) alternating current
c) open circuit voltage
d) arc voltage
a) direct current
Which term describes a piece of equipment used to create electricity of sufficient volume for welding?
a) transformer
b) resistor
c) inductor
d) generator
d) generator
This is a graphical illustration that plots the relationship between voltage and amperage output of a welding power source.
a) open circuit voltage
b) electromotive force
c) volt-amp curve
d) duty cycle
c) volt-amp curve
Which term expresses the strength of a current of electricity?
a) amperage
b) voltage
c) electron
d) conductor
a) amperage
When no current is flowing in the circuit, but the machine is turned on, you can measure the:
a) constant current.
b) open circuit voltage.
c) alternating current.
d) volt-amp curve.
b) open circuit voltage.
The speed at which AC changes direction is called the:
a) voltage.
b) amperage.
c) frequency.
d) resistance.
c) frequency.
This term describes the property of an electrical conductor that opposes the flow of current.
a) resistance
b) inductance
c) voltage
d) amperage
a) resistance
In welding, this term describes what is created when there is enough amperage and voltage to overcome the natural resistance to the flow of the electricity.
a) amp
b) volt
c) cycle
d) arc
d) arc
This welding machine transforms AC to DC.
a) line transformer
b) transformer rectifier
c) DC generator
d) AC transformer
b) transformer rectifier
This term describes one complete revolution of the AC generator.
a) circuit
b) core
c) coil
d) cycle
d) cycle
These machines convert high voltage, low amperage to low voltage, high amperage by the use of a primary and a secondary coil.
a) AC transformer
b) AC generator
c) DC generator
d) AC alternator
a) AC transformer
This term describes a material that can stop current flow through itself.
a) inductor
b) inverter
c) conductor
d) insulator
d) insulator
Electrode positive means:
a) straight polarity.
b) reverse polarity.
c) AC transformer.
d) alternating current.
b) reverse polarity.
Which term describes the typical sound of an AC transformer type welding machine?
a) turbine whine
b) high-pitched scream
c) buzz box
d) whisper quiet
c) buzz box
This type of welding machine is capable of changing DC to high frequency AC.
a) AC generator
b) DC rectifier
c) DC generator
d) inverter
d) inverter
What is the function of the secondary winding on a transformer welder?
a) to induce high frequency current
b) serves as a back-up in case the primary winding fails
c) to step down the voltage
d) to step down the amperage
c) to step down the voltage
One advantage of an AC transformer welder is freedom from:
a) undercut.
b) arc blow.
c) porosity.
d) slag inclusions.
b) arc blow.
What is the purpose of a silicon-controlled rectifier?
a) to change AC to DC
b) to change single phase to three phase
c) to increase the welding speed on aluminum
d) to change DC to AC
a) to change AC to DC
An advantage of an AC-DC transformer-rectifier welding machine is:
a) arc blow is not a problem.
b) purchase price is lower than AC transformer.
c) you have a choice of polarity.
d) does not have to be kept clean and cool.
c) you have choice of polarity.
How can you change the polarity on an AC generator welding machine?
a) Switch the cables at the machine.
b) Reverse the direction of the motor.
c) Change the polarity taps on the reactor coils.
d) An AC generator has no fixed polarity.
d) An AC generator has no fixed polarity.
What is one advantage of an engine-driven generator type welding machine?
a) lower cost
b) portability
c) less noise
d) less maintenance
b) portability
What is one disadvantage of all generator type welding machines?
a) higher maintenance costs
b) no choice of polarity
c) they are not portable
d) narrow choice of electrode types
a) higher maintenance costs
These welding power sources immediately rectify the incoming AC to DC and then transistors create a higher frequency AC. The higher frequency AC is then rectified to extremely smooth DC.
a) transformers
b) generators
c) buzz boxes
d) inverters
d) inverters
What is an advantage of an inverter type welding machine?
a) small and lightweight
b) generally cheaper to buy
c) portability
d) functions well in a dirty environment
a) small and lightweight
What is a disadvantage of an inverter type welding machine?
a) poor arc starting characteristics
b) higher input power requirements
c) initial cost is higher than transformers or rectifiers
d) cannot be configured for automation
c) initial cost is higher than transformers or rectifiers
Which is the largest cable size?
a) 4
b) 2
c) 2/0
d) 4/0
d) 4/0
Which size of welding cable would offer the most resistance to current flow?
a) 4
b) 2
c) 2/0
d) 4/0
a) 4
Overheating of the electrode holder can result from:
a) a poor connection between the cable and the holder.
b) using excessively long electrodes.
c) welding overhead instead of flat or horizontal.
d) using a permanently fixed work lead connection.
a) a poor connection between the cable and the holder.
How are electrode holders rated?
a) by voltage carrying capacity
b) by maximum electrode size
c) by amperage carrying capacity
d) by the size of welding cable used
c) by amperage carrying capacity
Loose work lead connections when using SMAW may cause:
a) electrical shock.
b) magnetic arc blow.
c) high burn-off rates.
d) arcing at the work clamp.
d) arcing at the work clamp.
An advantage to using a magnetic work lead device over a spring-loaded clamp is that the magnetic connection:
a) effectively prevents arc blow.
b) is less likely to damage the work by arcing.
c) is a permanently attached connection.
d) can be attached to all metals.
b) is less likely to damage the work by arcing.
If the welding cable from the machine is size 1/0, then the whip cable could be what size?
a) 4/0
b) 3/0
c) 2/0
d) 2
d) 2
