Welding Exam 50 Questions and Answers

🔧 Welding Exam: 50 Questions and Answers

Welding Exam: 50 Questions and Answers

Section 1: Safety (Q1–10)

1. What is the minimum shade lens for arc welding with currents over 200 amps?
   A) Shade #5
   B) Shade #10
   C) Shade #11
   D) Shade #14
   Answer: C

2. Which gas is most dangerous in a confined welding space?
   A) Oxygen
   B) Carbon Dioxide
   C) Nitrogen
   D) Carbon Monoxide
   Answer: D

3. What is the purpose of grounding the welding machine?
   A) To improve arc quality
   B) To prevent electrical shock
   C) To reduce noise
   D) To save electricity
   Answer: B

4. When should welding helmets be worn?
   A) Only during MIG welding
   B) While grinding
   C) During any arc welding operation
   D) Only when tacking
   Answer: C

5. The main hazard of UV light in welding is:
   A) Burns on hands
   B) Electrical shock
   C) Eye damage ("arc eye")
   D) Noise damage
   Answer: C

6. Which fire extinguisher type is used for electrical fires?
   A) Class A
   B) Class B
   C) Class C
   D) Class D
   Answer: C

7. Why should oxygen and fuel cylinders be stored separately?
   A) To save space
   B) To meet insurance policy
   C) To prevent fire hazards
   D) To increase welding speed
   Answer: C

8. The most common PPE for welding includes:
   A) Hard hat and sandals
   B) Welding helmet, gloves, jacket
   C) Safety goggles only
   D) Dust mask
   Answer: B

9. Before welding in a confined space, you should:
   A) Turn on a fan
   B) Leave the door open
   C) Test for toxic gases and ventilate
   D) Weld quickly
   Answer: C

10. Flash burn affects which part of the body most?
    A) Skin
    B) Eyes
    C) Ears
    D) Nose
    Answer: B

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Section 2: Welding Processes (Q11–25)

11. What does MIG stand for?
    A) Metal Inert Gas
    B) Metal Inside Gas
    C) Mild Iron Grinder
    D) Manual Internal Gas
    Answer: A

12. TIG welding is also known as:
    A) SMAW
    B) GMAW
    C) GTAW
    D) FCAW
    Answer: C

13. SMAW stands for:
    A) Semi-Manual Arc Welding
    B) Shielded Metal Arc Welding
    C) Small Metal Arc Welder
    D) Shielding MIG Aluminum Welding
    Answer: B

14. Flux-core welding uses what to protect the weld?
    A) External gas
    B) Internal flux
    C) Both A and B
    D) No shielding at all
    Answer: B

15. The electrode in TIG welding is typically made of:
    A) Copper
    B) Aluminum
    C) Tungsten
    D) Steel
    Answer: C

16. Which welding process requires a continuously fed wire and shielding gas?
    A) SMAW
    B) GMAW
    C) GTAW
    D) Oxy-fuel
    Answer: B

17. FCAW is commonly used in:
    A) Clean room environments
    B) Outdoor fabrication and construction
    C) Jewelry making
    D) Auto body shops
    Answer: B

18. Oxy-acetylene welding uses which gases?
    A) Oxygen and propane
    B) Oxygen and acetylene
    C) Helium and acetylene
    D) Propane and argon
    Answer: B

19. In MIG welding, the most common shielding gas is:
    A) Helium
    B) Oxygen
    C) Argon/CO₂ mix
    D) Acetylene
    Answer: C

20. Arc blow is most common in:
    A) AC welding
    B) DC welding
    C) Oxy-fuel welding
    D) TIG welding
    Answer: B

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Section 3: Materials and Metallurgy (Q26–35)

21. Stainless steel contains a minimum of what element to resist corrosion?
    A) Nickel
    B) Copper
    C) Chromium
    D) Zinc
    Answer: C

22. Aluminum welding typically uses which polarity in TIG welding?
    A) DCEN
    B) DCEP
    C) AC
    D) None
    Answer: C

23. Hardness is a measure of a material’s:
    A) Strength
    B) Brittleness
    C) Resistance to deformation
    D) Toughness
    Answer: C

24. Preheating is most commonly used to prevent:
    A) Arc blow
    B) Cold lap
    C) Cracking
    D) Oxidation
    Answer: C

25. Which metal requires a wire brush dedicated for it due to contamination risks?
    A) Copper
    B) Mild Steel
    C) Aluminum
    D) Titanium
    Answer: C

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Section 4: Symbols, Measurements, and Defects (Q36–45)

26. The symbol for a fillet weld is:
    A) —
    B) ⊥
    C) ∟
    D) ∩
    Answer: C

27. What does a “tail” on a welding symbol typically contain?
    A) Weld size
    B) Process information
    C) Base metal
    D) Wire type
    Answer: B

28. A porosity defect is caused by:
    A) Slow travel speed
    B) Moisture or contamination
    C) High amperage
    D) Excessive wire feed
    Answer: B

29. Undercut is a defect that appears as:
    A) A raised weld bead
    B) A groove along the weld toe
    C) Extra filler metal
    D) A pinhole
    Answer: B

30. A welding gauge is used to measure:
    A) Voltage
    B) Weld thickness and profile
    C) Amperage
    D) Shielding gas flow
    Answer: B

31. In a welding symbol, an arrow pointing to the joint indicates:
    A) Location for measuring
    B) The side to weld on
    C) Joint thickness
    D) Heat affected zone
    Answer: B

32. Incomplete fusion means:
    A) Too much weld metal
    B) Weld didn’t penetrate base metal properly
    C) Overheated metal
    D) Perfect weld
    Answer: B

33. Weld size is often indicated on the symbol by:
    A) A number above the reference line
    B) A number below the weld symbol
    C) A letter in the tail
    D) There’s no size indication
    Answer: B

34. A convex weld shape is:
    A) Sunken in the middle
    B) Flat
    C) Slightly raised or rounded
    D) Angled outward
    Answer: C

35. The root opening is:
    A) Width of the weld bead
    B) Distance between parts at joint root
    C) Weld height
    D) Travel speed
    Answer: B

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Section 5: Practical/Advanced (Q36–50)

36. Travel speed that's too slow can cause:
    A) Cold lap
    B) Burn-through
    C) Undercut
    D) Incomplete penetration
    Answer: B

37. What is the "heat-affected zone" (HAZ)?
    A) The melted filler metal
    B) The arc itself
    C) The base metal altered by heat but not melted
    D) The weld bead
    Answer: C

38. Which electrode is best for welding out-of-position?
    A) 6010
    B) 7018
    C) 7024
    D) E308L
    Answer: A

39. 6010 electrodes operate on:
    A) AC only
    B) DC only
    C) AC or DC
    D) None of the above
    Answer: B

40. The first two digits of 7018 indicate:
    A) Strength of 70,000 psi
    B) Polarity
    C) Rod diameter
    D) Penetration depth
    Answer: A

41. A welding procedure specification (WPS) includes:
    A) Wire length only
    B) Travel direction only
    C) All variables needed to make a sound weld
    D) Voltage setting only
    Answer: C

42. Back gouging is used to:
    A) Start a weld
    B) Increase penetration
    C) Remove defects from root pass
    D) Weld thick plates
    Answer: C

43. What is the function of a contact tip in MIG welding?
    A) Stabilize arc
    B) Feed gas
    C) Transfer current to wire
    D) Remove spatter
    Answer: C

44. The duty cycle of a welding machine indicates:
    A) Weld speed
    B) How long it can run without overheating
    C) Gas flow rate
    D) Electrode size
    Answer: B

45. Weaving in welding helps with:
    A) Travel speed
    B) Weld reinforcement
    C) Wider bead coverage
    D) Amperage control
    Answer: C

46. Push technique in MIG welding results in:
    A) Better penetration
    B) Cleaner welds
    C) More spatter
    D) Narrow bead
    Answer: B

47. Stringer beads are used when:
    A) Wide weld is needed
    B) Vertical or overhead welding
    C) Increased deposition needed
    D) Weaving is preferred
    Answer: B

48. Arc length in stick welding should be approximately:
    A) 2 times the rod diameter
    B) 1/16 inch
    C) Equal to electrode diameter
    D) 1 inch
    Answer: C

49. The puddle in welding is:
    A) A defect
    B) The molten metal pool
    C) Electrode tip
    D) Base plate edge
    Answer: B

50. Which process allows welding of thin materials with great control?
    A) Stick
    B) MIG
    C) TIG
    D) FCAW
    Answer: C