Computerized cutting Flashcards
What type of metals can be cut by plasma arc
Almost All types
Describe plasma cutting process
A process that uses high velocity jet ionized gas delivered from Constricting Orfice
What are some safety practises when operating plasma
Long sleeves gloves high protection dark goggles or welding shield
What happens if the nozzle is not in place for a safety safety feature
If it’s not in place in arc will not start
What are components of plasma
The shield ,retaining cap ,nozzle ,electrode and swirl ring
What are consumable parts on Plasma machine
Electrode and nozzle
If you cut thick metal what type of machine should you get
Higher amp machine
What is kerf
Avoid created by plasma cutting or the metal that was removed
What should the opening of the bottom die be on stainless steel fabrication
At least eight times material thickness
Martenstic and ferriitic metals are high weldables
No. They are low
What joint is not recommended for use of stainless steel
Lap joint
What type of tungsten should be used for stainless steel
1/16 of an inch or 2% pure
Should the filler rod matcher base metal
Yes
Does Stan still have low thermal conductivity 
Yes
What is a reasonable tip size for a spot welds
Eighths of an inch +2 metal thicknesses
What angle should you hold your angle grinder
10°
What happens when chromium Contant exceeds 11%
Invisible film is form to protect material
Can stainless steel rust
Yes one film is contaminated by iron
How many groups and series are there for stainless steel
Four groups too serious
What is the film form on stainless steel
Chromium oxide
Three ways stainless steel could be contaminated
Using mild steel drive chuck
Using a abrasives with mild steel
Dirty bench

What are two ways to compensate for spring back
Overbending
Breaking and coining
Advantage of air bending
Greater variety less tonnage less damage
What What amperage is required for Tig welding 16 gauge stainless steel
80-100
It is preheating and post heating required when welding most austentic stainless steel
No
Stainless steel has ……%Greater Co-efficiency thermal expansion and ….. Thermal conductivity
50
1/3
Three methods controlling distortion when welding stainless steel
Copper chill plates
skip welding
step back welding
What are some considerations spot welding stainless
Increase electrode pressure decrease amperage and wild time
Define finishing in regards to stainless steel
To give desired surface effect
Procedure required to finish welds on stainless steel to mirror finish
Grind
sand
polish
buff
What is the lightest shade for welding lens recommended for gas tungsten arc welding
10
What is three dangers welding gloves protect us from
UV rays
heat
electric shock
Why is it not recommended to run gas cylinders 0 psi
It prevents atmosphere contamination
Is GTAW a good choice when welding outdoors
No shielding gas will displace
What is the purpose of high frequency current for DC
Arc starting
What is the purpose for high frequency current for AC welding
Arc starting
arc stability
gas ionization
Five components of an air cooled torch
Torch body
Calletbody
Gas lens
Nozzle
Cap
Electrode
What is the opening diameter of a number six gas nozzle
3:8
Define laminar
Arranged in thin layers
What is the purpose of Shielding gas
Exclude the atmospheric from the weld
Is it more accurate to measure gas flow by volume or pressure
Pressure
How many numbers to Determining filler rod
Two numbers mild steel three numbers stainless steel four numbers aluminum
Why is aluminum best Welded on AC current
It provides cleaning Action
What would cause a weld to have a lack of fusion
Arc length too long
current setting to low
bad prep
Types of tungsten used for welding aluminum
Pure tungsten
2% Cerium 
2% thorium
Fillet weld
Inside corner weld
What is the effect of a finer point on a tungsten when Tig welding stainless
Deeper penetration
Two ways to cut aluminum
By hand or Beverly shear
When brake forming heavy gauge aluminum what works best
Press brake
What temperature does oxide layer for Aluminum melt
3200 melts at 1200
Aluminum Electroid uses bald end true or false
True
How does flow metre read
Cubic ft.³/hour or litres per minute
What should the inside diameter of the gas cap be
Three times the tungsten diameter
With a single spot weld. If metal is twisted at what angle will it break
60-90
Three disadvantages of GTAW
Slow speed , can’t weld outdoors , tungsten might break in weld
Which material distorts the most when welded
Stainless steel by 50%
What’s the gas flow range for stainless steel
10-30 cfh
Stainless steel oxidation is known as
Sugaring , chromium oxide
What metal is a greater conductor ? Aluminum or stainless
Aluminum
If the gas in the cup is not giving complete coverage while welding , what must be done
Use a larger size
CnC safety features
Nozzle in place
Pre flow sequence
Plasma cutting is done with what three gases
Argon
Nitrogen
Oxygen
Good bevel cut on cnc
1-3 is good
3-8 is bad
What safety feature is there so you don’t get 300 v of dC current
Nozzle in place
Duty cycle is done how many minutes
10 min
Slow cutting leaves vertical lag lines
True
Dross should be removed by
Grinding