Weekz 2 Flashcards
An electric current that reverses its direction at regularly recurring intervals
Alternating current
A depression at the joint root between the workpieces
Root opening
What are the welding positions
Flat, horizontal, vertical, overhead
The junction between the face of the weld and the base metal
Toe of a weld
AWS
American welding Society
Duties cycle is defined as the ratio of __ time to __ time
Arc, total
What to do to prevent undercutting
Pause at each side of the weld bead when using a weaving technique
Slang term for shielded metal arc welding
Stick welding or stick electrode welding
Straight polarity
DCEN
Reverse polarity
DCEP
The covering on the electrode dictates the usability of the electrode and provides
1.
2.
3.
4.
5.
6.
- Gas from the decomposition of certain ingredients of the coating to shield the arc from the atmosphere
- Deoxidizers for purifying the deposited weld metal.
- Slag formers to protect the deposit weld metal from oxidation.
- Ionizing elements to make the arc more stable and the electrode operates more smoothly with alternating current.
- Alloying elements to provide a special characteristics to the deposited weld metal.
- Iron powder to improve the productivity of the electrode.
An electric arc process that produces coalescence of metals by heating them with an arc between a continuous filler metal electrode, and the workpiece, shielding is entirely from an external supply gas
GMAW
What type of current is used for GMAW
Direct current electrode positive
What does the wire feeder do in gas metal arc welding?
The wire feeder drives the electrode from the wire spool through the cable and gun to the arc
How is the push system designed?
So that the wire feed rolls are near the wire supply and the wire is pushed through the wire conduit to the welding gun or torch
What displaces the air around the arc to prevent contamination of the molten pool by oxygen and nitrogen in the atmosphere? GMAW
Shielding gas
The electrode wire for _______ is solid and bear. Steel wires normally have a thin ____ coating to improve electrical pick up and protect the wire from oxidation
GMAW, copper
In what process is shielding provided by a flux contain within the tubular electrode
Flux corded arc welding
True or false
a layer of slag is produced on the world bead, which must be removed after welding in FCAW
True
What current is used with no gas shield
DCEN
Which process produces a coalescence of metals by heating them with an arc between a tungsten electrode, and shielded with gas
GTAW
In GTAW The welder controls the ___ with one hand and feeds the ____ ____ with the other
Torch, filler metal
What does letting up on the foot pedal but not completely in TIG do?
Decreases current
What current should you use when welding aluminum?
AC
Air cooled torches are designed for ____ duty, welding, and water cool torches are used for ___ duty welding
Light, heavy
What electrode has the highest melting point of all metals and is virtually impossible to vaporize when used correctly
Tungsten electrode
What two very important characteristics are the reason tungsten is used
High melting point and excellent electrical conductor
What two gases are most commonly used with TIG welding
Argon and helium
When TIG welding heavier materials, ___ amperage is required
Higher
Why is reverse polarity not used when welding with TIG
It will melt the tungsten electrode
What will cut metals such as bronze brass, copper galvanized, steel coated or painted steel, mild steel, stainless steels
Plasma arc cutting
Plasma is a thermal cutting process. It cuts anything that conducts ___ and ___
Heat and electricity
What process is popular for cutting metal gouging out defects removing poor welds back gouging route passes and preparing joint edges
Air carbon arc cutting
True or false
Before welder can begin work on any job covered by a welding code qualification under the code that applies is required
True
True or false
If the welder uses a different process or the welding procedure is altered drastically requalification is required
True
What is the most widely used and popular welding inspection technique?
Visual inspection
What is a highly sensitive non-destructive method for detecting my new discontinuity such as cracks, pores, and porosity
Liquid penetrate inspection
Identify eight ways to control distortion
