Welding Flashcards
Fire requires what?
Fuel, heat, oxygen
Name the 3 harmfull light rays?
Visible - eyes strain
Ultra Violet - burn or blister eye balls
Infrared - cataracts
Classes of Fire
A-wood
B-Liquids
C-electric
D-combustibles
In the event of Flashback what do you shut off first?
Oxygen
What safety features do Oxygen tanks have?
- The tank is made from a single piece of steel with no seems.
- The cylinder valve is double seats (seals when fully open and fully closed) and the valve has a rupture disc that will burst if the pressure exceeds 3200 psi, allowing a slow release of gas
Safety features of acetylene tanks?
-fusible plugs melt at 212 degrees F
-tank safety stored at 250 psi
-
What is a Oxygen tank fully charged at?
2200 psi
What gas is colourless but stinks?
Acetylene
What gas is colourless, odourless and tasteless?
Oxygen
Straight polarity - electrode negative
Electrode is connecting to the negative terminal
Reverse polarity - electrode positive
Electrode is connected to the positive. Burns slower enabling deeper penitration
What type of electrode do you use to check polarity
E6010
What are 3 types if constant power sources?
Transformers
Inverters
Generators
What is duty cycle?
Quality of components inside welder. Allows welding to operate at that percentage of its amperage
What does voltage cause the electrode to do?
Flow in a conductor or cross a gap. It maintains the arc and puddle fluidity and flow
What does amperage cause the electrode to do?
To melt. It is the heat for welding.
What is a carbonizing flame and it’s used?
Rich in acetylene. Adds carbon. Hard surfacing, fusion welding of alloy steels and med - high carbon steels and brazing
Two methods of piercing holes?
Travelling torch or still torch
What are drag or lag lines?
Lines on the side of the work piece caused by the oxygen jet stream.
What part of the torch is susceptible to backfires?
Tip and mixer
What 2 things are put into an acetylene tank so the gas remains stable?
A porous filler mass and 40% of the tank is filled with acetone
Four principle functions of Flux?
- prevent oxidization during heating
- absorb and remove oxides
- assist in the flow of the filler
How is strength and size determined in a fillet weld?
- Strength from throat size of largest equal leg triangle.
- Size from length of the largest equal leg triangle
