Physics of welding
The flux coating on an SMAW electrode contributes to weld quality by?
Producing shielding gases and slag to protect the molten weld pool
Why is a welding helmet with the proper shade lens required during the SMAW process?
To protect the eyes and face from UV/IR radiation and arc flash
What is the primary function of the flux coating on a SMAW electrode?
Produce shielding gas and slag to protect the weld puddle
What type of drawing is most commonly used to show multiple views (top, front, side) of a welded part?
Orthographic projection
What is the primary purpose of performing routine maintenance on an SMAW machine?
Ensure safe and reliable machine operation
In SMAW, electrons flow from the negative terminal to the positive terminal. When using DCEP (reverse polarity), the majority of heat is concentrated?
At the base metal
Before changing electrodes in SMAW, what personal safety step should be taken?
Ensure the electrode holder is insulated and avoid contact with the electrode tip
In SMAW, what type of power source output is most commonly used?
Constant Current (CC)
On a welding symbol, the information placed below the reference line indicates
The weld is on the arrow side
Before performing any maintenance on an SMAW welder, the first step should be to
Disconnect power and follow lockout/tagout procedures
Why does increasing amperage in SMAW generally increase penetration?
It increases total heat input into the weld joint
Why must the work clamp be properly secured to clean metal before welding?
To ensure proper electrical circuit and reduce shock hazard
Which component completes the electrical circuit in SMAW?
Work clamp attached to the base metal
In SMAW welding drawings, a triangle placed on the reference line represents
Fillet weld
Which of the following is a common sign of a worn electrode holder?
Loose electrode grip or overheating of handle
What is the primary method of heat generation in the SMAW welding arc?
Electrical resistance and ionization of the arc gap
What is the safest action to take before striking an arc in the SMAW process?
Verify all nearby personnel have proper eye protection or welding shields in place
During SMAW welding, the electrode serves what dual purpose?
Conducts current and becomes the filler metal
If a welding symbol includes “E7018” in the tail, this indicates:
Required electrode classification
Accumulated dust inside an SMAW power source can
Cause overheating and electrical component failure
Why does steel expand when heated during welding?
Atomic vibration increases, causing atoms to spread apart
As temperature rises, atomic movement increases, causing expansion. This expansion and contraction contribute to weld distortion.
Why must cylinders and gas bottles in the lab be secured upright even when performing SMAW welding?
To prevent tipping, which can cause serious injury or equipment damage
If an electrode repeatedly sticks to the base metal, the most likely cause is
Amperage set too low
A section view is used on a drawing to
Show internal features clearly
Why is it important to periodically check the tightness of cable lugs?
To prevent voltage drop and overheating at connections