120103g GMAW FCAW and MCAW Groove Welds on Mild Steel Flashcards
GMAW FCAW and MCAW Groove Welds on Mild Steel
What are two (2) advantages of using more than one process to complete a weld?
a) The cost of welding is reduced in many cases if the advantages of each process are applied to the fabrication.
b) It increases production while maintaining high-quality weld metal.
Explanation: Using multiple processes can optimize both cost and production efficiency.
What is the root pass, and where is it located on a Vee groove joint preparation?
The root pass is the first penetrating bead. It is placed at the root of the joint.
Explanation: The root pass is crucial for the integrity of the weld, ensuring deep penetration at the base.
The electrode wire type is selected to match the:
a) shielding gas.
b) welder’s preference.
c) thickness of the parent metal.
d) chemical and mechanical properties of the base metal.
d) Chemical and mechanical properties of the base metal.
Explanation: The electrode wire must match the base metal’s properties for a quality weld.
What is the recommended electrode angle on a groove weld?
a) 1/4 of the included angle
b) 1/2 of the included angle
c) 3/4 of the included angle
d) the same as the included angle
b) ½ of the included angle.
Explanation: This angle ensures proper penetration and fusion of the weld.
What is the recommended inclination for the FCAW fill passes in the 1G position?
a) forehand 10°-30°
b) forehand 90°
c) backhand 0° - 10°
d) backhand 90°
c) Backhand 0° - 10°.
Explanation: This inclination aids in better control and penetration in the 1G position.
What is the recommended inclination for the MCAW fill/cap passes in the 2G position?
a) Forehand 0° - 10°
b) Forehand 45°
c) Backhand 45°
d) Backhand 20° - 30°
Answer: a) Forehand 0° - 10°
Explanation: This inclination aids in controlling the weld pool and ensures effective welding in the 2G position.
What mode of metal transfer is used with FCAW?
a) Pulsed spray
b) Spray
c) Short circuit
d) Globular
Answer: d) Globular
Explanation: Globular transfer in FCAW involves large droplets transferred across the arc.
What mode of metal transfer is used with MCAW in the 3G position?
a) Pulsed spray
b) Spray
c) Short circuit
d) Globular
Answer: a) Pulsed spray
Explanation: Pulsed spray in MCAW provides controlled metal transfer, beneficial for vertical position welding.
Name four (4) factors that can influence flow meter settings with GMAW and FCAW.
Answer: Any four of the following are correct:
a) Type and thickness of material to be welded
b) Position of weld
c) Type of joint
d) Diameter of wire
e) Puddle size
f) Air movement around the weld zone
g) Gun inclination
h) Nozzle-to-work distance
Explanation: These factors affect the shielding gas coverage, influencing weld quality.
List four (4) GMAW welding parameters.
Answer: Any four of the following are correct:
a) Shielding gas type
b) Shielding gas flow rate
c) Wire speed setting
d) Voltage setting
e) Transfer mode
Explanation: Correctly setting these parameters is crucial for achieving the desired weld quality.
What type of equipment set-up is recommended for high production welding using GMAW and FCAW or MCAW?
a) Constant current power source, dual drive roll wire feeder
b) Constant voltage power source, dual drive roll wire feeder
c) Constant current power source, single drive roll wire feeder
d) Constant voltage power source, single drive roll wire feeder
Answer: b) Constant voltage power source, dual drive roll wire feeder
Explanation: This setup provides a stable voltage and efficient wire feeding, essential for high production welding.
What type of interpass cleaning is normally required between the GMAW root pass and FCAW or MCAW deposited weld metal?
a) Grind to clean weld metal before proceeding.
b) De-slag before proceeding.
c) Hand brush before proceeding.
d) Interpass cleaning is not normally required.
Answer: d) Interpass cleaning is not normally required.
Explanation: The nature of these processes often makes interpass cleaning unnecessary.
Explain why it is important to always start at the bottom and layer upwards when placing stringer bead fill and cap passes in the 2G position.
Answer: This prevents weld metal from rolling down and causing overlap or lack of fusion.
Explanation: Proper sequencing ensures good fusion and prevents defects in horizontal welding.
