What forms ozone? - ANS-When oxygen and atmospheric air comes in contact with ultraviolet
light
Chlorinated solvents such as brake clean combined with ultraviolet light create? -
ANS-Phosgene gas
dizziness and euphoria are signs of? - ANS-Oxygen difficiency
Most wire fed applications use what type of current - ANS-Direct current reverse polarity, DCRP
A wire feeder system includes what? - ANS-Drive roll system, variable speed motor
Gun and cable assemblies are rated by what? - ANS-Current carrying capacity
What is the purpose of a shielding gas - ANS-Protect weld metal from atmospheric air
The regulator does what? - ANS-reduces gas source pressure to a working pressure
What do flow metres do? - ANS-Indicate volumetric flow rate in liters, per minute or cubic feet
per hour
Construction of power sources and duty cycles are meant to specification of who? - ANS-NEMA
What type of volt amp curve does CV machines have? - ANS-Relatively flat volt amp curve
What type of volt amp curved do cc machines have - ANS-Drooping volt amp curve
Filler wires must be manufactured to? - ANS-Match the chemistry of base metal and mechanical
properties such as tensile strength, ductility and impact strength
What csa specification covers filler metals - ANS-Csa w48
What three types of wire drive systems are there - ANS-Push, pull and push pull
Where are the drive rolls located in a push system - ANS-In the wire feed unit
In a push system what is the max distance of cable - ANS-15ft
Where are the drive rolls located in a pull system - ANS-Mounted in the gun close to the contact
tip
, What problem does the pull system overcome - ANS-Wire hang ups with soft wires
What type of wire is used in a pull system - ANS-Small diameter or soft electrode wires such as
aluminum wires
What is a pull system also known as - ANS-Spool on gun
Push pull system has drive rolls where - ANS-The gun and wire feeder
A push system is normally used for what types of welding? - ANS-Gmaw, fcaw and mcaw
Constant speed wire feeders use what power source - ANS-CV
Voltage sensing wire feeders use what power source - ANS-CC
CV power sources automatically adjust what - ANS-Amperage output as the stick out changes
Voltage sensing wire feeders set speed according to what - ANS-Arc voltage
V groove and u groove drive rolls are used for what types of wires - ANS-Solid wire, as they
provide a 3 point contact to grip the wire with minimum pressure while maintaining the wires
shape
Serrated or knurled drive rolls used for what type of wires? - ANS-Flux cored and metal cored
wires (hollow wires)
When you change wire size what should you also change - ANS-Drive rolls
Contact tubes do what? - ANS-Transfer electrical current to the electrode and direct wire to weld
zone.
Contact tubes are specific to what? - ANS-Size of wire
In short circuit mode of transfer your contact tube should be - ANS-Flush or extended
Nozzles do what - ANS-Direct shielding gas onto weld zone
What type of liner is recommended for hard wires - ANS-Stainless steel helical liners
What type of liner is recommended for soft wires (aluminum) - ANS-Nylon Teflon or plastic
What is cast - ANS-The diameter formed by one loop of a maximum of 10 feet of electrode wire
when cut from a package and laid unrestrained on a flat surface (curve a wire has off a spool)