Welding Defects: Causes, Prevention, and Correction Techniques

Question 1

Identify the primary cause of porosity in welded joints:

Accepted Answer

Insufficient shielding gas

Answer

Excessive welding pace

Answer

Contaminated base metal

Answer

Excessive heat input

Question 2

What is the primary factor contributing to porosity in welds?

Accepted Answer

Entrapped air or moisture

Answer

Excessive shielding gas

Answer

Insufficient shielding gas

Answer

Improper welding angle

Question 3

What is the most effective method to prevent inclusions in welds?

Accepted Answer

Thoroughly cleaning the weld area

Answer

Using a welding flux

Answer

Increasing the welding speed

Answer

Using a smaller welding electrode

Question 4

When repairing cracks in welds, what is the preferred course of action?

Accepted Answer

Grinding out the crack and re-welding

Answer

Applying a weld overlay

Answer

Using a chisel to remove the crack

Answer

Ignoring small cracks

Question 5

What is the primary goal of post-weld heat treatment?

Accepted Answer

Relieving residual stresses

Answer

Enhancing weld strength

Answer

Reducing weld porosity

Answer

Preventing corrosion

Question 6

According to the AWS classification system, which electrode is suitable for welding mild steel?

Accepted Answer

E7018

Answer

E6010

Answer

E308

Answer

E410

Question 7

Which of these is NOT a typical welding flaw?

Accepted Answer

Corrosion resistance

Answer

Porosity

Answer

Undercut

Answer

Stress cracking

Question 8

Which of the following is not a welding defect?

Accepted Answer

Corrosion

Answer

Porosity

Answer

Hot cracking

Answer

Lamellar tearing

Question 9

To prevent weld porosity, which action should a welder prioritize?

Accepted Answer

Shield the weld area from atmospheric gases

Answer

Increase welding speed

Answer

Reduce welding voltage

Answer

Use a higher welding current

Question 10

What is the primary reason behind porosity in welded joints?

Accepted Answer

Trapped gases

Answer

Contaminated base metal

Answer

Inappropriate welding technique

Answer

Excess moisture in the shielding gas

Question 11

Which non-destructive testing method is specifically designed to detect internal welding flaws?

Accepted Answer

Ultrasonic testing

Answer

Magnetic particle testing

Answer

Dye penetrant testing

Answer

Visual examination

Question 12

To prevent undercut in welds, which of the following practices is recommended?

Accepted Answer

Maintaining a correct electrode angle

Answer

Increasing the welding current

Answer

Welding in the vertical position

Answer

Using a faster welding speed

Question 13

What is the objective of post-weld heat treatment?

Accepted Answer

To relieve residual stresses and improve toughness

Answer

To enhance weld strength primarily

Answer

To minimize porosity in welds

Answer

To reduce corrosion resistance

Question 14

What is the fundamental purpose of a welding procedure specification?

Accepted Answer

To document standardized welding practices and quality requirements

Answer

To provide information on welding tools and equipment

Answer

To specify welder qualifications exclusively

Question 15

What are the typical characteristics of a cold weld?

Accepted Answer

Lack of fusion, grainy appearance

Answer

Smooth surface, high strength

Answer

Uniform color, fine grain structure

Question 16

In repairing welding defects, which method is most commonly employed?

Accepted Answer

Re-welding

Answer

Riveting

Answer

Cold forming

Answer

Machining

Question 17

Which of the following welding defects is characterized by voids or cavities within the weld metal?

Accepted Answer

Porosity

Answer

Cracking

Answer

Undercut

Answer

Slag inclusion

Question 18

Which preventive measure is recommended to minimize spatter during welding?

Accepted Answer

Employing an anti-spatter spray

Answer

Reducing the welding travel speed

Answer

Using an excessively large electrode

Answer

Increasing the welding current

Question 19

What type of welding defect occurs when the weld metal fails to fully penetrate the joint?

Accepted Answer

Lack of penetration

Answer

Cold lap

Answer

Slag inclusion

Answer

Underfill

Question 20

What is the primary purpose of utilizing a welding rod?

Accepted Answer

To provide additional material for filling the weld joint

Answer

To protect the weld from atmospheric contamination

Answer

To guide the welding torch

Answer

To generate the electric arc

Question 21

Which of the following is NOT a type of welding electrode?

Accepted Answer

Inert gas

Answer

Gas tungsten arc welding (GTAW)

Answer

Shielded metal arc welding (SMAW)

Question 22

What is the crucial function of a welding helmet?

Accepted Answer

To shield the welder's eyes and face from harmful radiation

Answer

To regulate the welding current

Answer

To provide ventilation during welding

Question 23

What is the primary reason for preheating a metal before welding?

Accepted Answer

To reduce internal stresses and prevent cracking

Answer

To enhance weld penetration

Answer

To increase welding speed

Answer

To improve the metal's conductivity

Question 24

Which welding defect is primarily characterized by voids or cavities within the weld metal?

Accepted Answer

Porosity

Answer

Undercut

Answer

Slag Inclusion

Answer

Lack of Fusion

Question 25

Which welding defect is a significant concern due to its potential to create stress concentrations and lead to premature failure?

Accepted Answer

Cracking

Answer

Porosity

Answer

Slag Inclusion

Answer

Undercut

Question 26

What is the best method to effectively prevent slag inclusions in welds?

Accepted Answer

Ensure proper cleaning of the weld bead after each pass

Answer

Use a larger diameter electrode

Answer

Increase welding current

Question 27

Which welding defect is strongly influenced by the cooling rate of the weld metal?

Accepted Answer

Cracking

Answer

Incomplete Penetration

Answer

Slag Inclusion

Answer

Porosity

Question 28

Why is it essential to address 'incomplete penetration' in welds?

Accepted Answer

It weakens the structural integrity of the joint

Answer

It affects the aesthetic appearance of the weld

Answer

It increases the risk of porosity

Question 29

Which of the following is NOT a recommended method for correcting welding defects?

Accepted Answer

Increasing welding current to melt away defects

Answer

Grinding and re-welding

Answer

Using a different welding process

Answer

Chipping out defects and filling with filler metal

Question 30

What is the most effective strategy to prevent welding defects?

Accepted Answer

Following proper welding procedures and techniques

Answer

Using only the most expensive welding equipment

Answer

Hiring experienced welders

Question 31

Which welding defect is characterized by isolated cavities within the weld metal caused by entrapped gas?

Accepted Answer

Porosity

Answer

Cracking

Answer

Undercut

Question 32

Which technique is effective in preventing 'undercut' during welding?

Accepted Answer

Maintaining a consistent travel speed and using an appropriate electrode angle

Answer

Increasing welding current

Answer

Using a larger electrode diameter

Question 33

What is the primary cause of 'slag inclusion' defects in welding?

Accepted Answer

Incomplete removal of slag from previous weld passes

Answer

Improper selection of welding electrodes

Answer

Excessive welding speed

Question 34

Which welding defect is characterized by a groove along the edge of the weld, weakening the joint?

Accepted Answer

Undercut

Answer

Burn-through

Answer

Slag Inclusion

Answer

Cracking

Question 35

What is the primary factor that contributes to 'cracking' in welded joints?

Accepted Answer

Residual stresses and rapid cooling

Answer

Insufficient preheating

Answer

Improper electrode selection

Answer

Excessive welding speed

Question 36

Which welding parameter should be adjusted to minimize the risk of 'burn-through'?

Accepted Answer

Reducing welding current

Answer

Using a larger electrode diameter

Answer

Increasing welding speed

Question 37

Which welding defect is most likely to occur due to insufficient inter-pass cleaning during multi-pass welding?

Accepted Answer

Slag Inclusion

Answer

Cracking

Answer

Undercut

Answer

Porosity

Question 38

What is the most effective measure to minimize the risk of 'porosity' in welded joints?

Accepted Answer

Proper cleaning of the weld area and using the appropriate shielding gas

Answer

Increasing welding current

Answer

Using a larger electrode diameter

Question 39

Which factor primarily causes porosity in welded joints?

Accepted Answer

Trapped gases

Answer

Insufficient heat input

Answer

Impurities in the base metal

Answer

Improper joint preparation

Question 40

What is the primary effect of a cold lap defect on a welded joint?

Accepted Answer

Reduced strength

Answer

Increased porosity

Answer

Slag inclusions

Answer

Excessive weld bead

Question 41

What is the main purpose of visual inspection in welding quality control?

Accepted Answer

To detect surface defects

Answer

To assess the weld's resistance to corrosion

Answer

To determine the weld's internal strength

Answer

To measure the weld's chemical composition

Question 42

Which of these testing methods damages the weld to evaluate its quality?

Accepted Answer

Tensile testing

Answer

Ultrasonic testing

Answer

Dye penetrant testing

Answer

Magnetic particle testing

Question 43

What is the primary goal of applying heat treatment after welding?

Accepted Answer

To reduce internal stresses

Answer

To prevent rust and corrosion

Answer

To improve the weld's appearance

Answer

To increase weld hardness

Question 44

Which welding defect appears as a crack running alongside the weld bead?

Accepted Answer

Hot crack

Answer

Underbead crack

Answer

Cold crack

Answer

Crater crack

Question 45

What is the leading cause of lamellar tearing in a welded joint?

Accepted Answer

High sulfur content in the base metal

Answer

Improper pre-weld cleaning

Answer

Using an incorrect welding process

Answer

Insufficient shielding gas coverage

Question 46

Which welding defect is characterized by a void or cavity within the weld metal, often caused by gas entrapment?

Accepted Answer

Porosity

Answer

Cracking

Answer

Undercut

Answer

Lack of Fusion

Question 47

A weld with a sharp, angular groove along the edge of the weld bead, often caused by improper welding technique or excessive travel speed, is known as:

Accepted Answer

Undercut

Answer

Incomplete Penetration

Answer

Overlap

Question 48

Which of the following is NOT a primary cause of weld cracking?

Accepted Answer

Excessive welding speed

Answer

Rapid cooling rate

Answer

Hydrogen embrittlement

Answer

Residual stresses

Question 49

A weld defect where the weld metal does not completely fuse with the base metal is called:

Accepted Answer

Lack of Fusion

Answer

Incomplete Penetration

Answer

Burn-through

Answer

Slag Inclusion

Question 50

Which welding defect is most likely to occur due to improper cleaning of the weld joint before welding?

Accepted Answer

Slag Inclusion

Answer

Cracking

Answer

Undercut

Answer

Porosity

Question 51

What is the primary way to prevent excessive weld shrinkage and associated distortion?

Accepted Answer

Proper preheating of the base metal

Answer

Increasing the welding speed

Answer

Using a higher welding current

Question 52

Which of the following is NOT a common method for correcting welding defects?

Accepted Answer

Applying a high-temperature torch to the weld area

Answer

Grinding or machining the defect

Answer

Re-welding the defective area

Question 53

A weld with a visible bulge or protrusion beyond the intended weld joint is known as:

Accepted Answer

Overlap

Answer

Undercut

Answer

Incomplete Penetration

Answer

Burn-through

Question 54

Which welding defect is most likely to occur when the welding current is too low?

Accepted Answer

Incomplete Penetration

Answer

Porosity

Answer

Burn-through

Answer

Undercut

Question 55

What is the primary purpose of using a welding inspection technique like radiographic testing?

Accepted Answer

To detect internal defects such as cracks or voids

Answer

To assess the weld's surface finish

Answer

To verify the type of welding process used

Answer

To measure the weld bead size