Deck 16: Weld Discontinuity and Defects

Question 1

The two most common causes of porosity are improper welding techniques and _____. ​

A)heat​
B)shielding gas​
C)nitrogen​
D)contamination​

Answer 1

D

Question 2

_____ refers to the small bubbles of gas that appear in solid weld metal. ​

A)Porosity​
B)Discontinuity​
C)Defect​
D)Flaw​

Answer 2

A

Question 3

All welds have discontinuities and flaws, but they are not necessarily _____. ​

Answer 3

defects

Question 4

Overlap is also referred to as _____. ​

A)hot lap​
B)cold lap​
C)undercut​
D)underfill​

Question 5

The localized hardening of an arc strike is the result of the _____ effect of it by the surrounding metal. ​

A)cooling​
B)heating​
C)quenching​
D)hardening​

Question 6

_____ are the result of internal stresses within a weld or surrounding metal that exceed the ultimate strength of the metal. ​

A)Cracks​
B)Delaminations​
C)Laminations​
D)Overlaps​

Question 7

_____ are foreign objects not melted by the weld are that are left in the weld groove as weld metal is deposited over them. ​

Question 8

What are some of the surface impurities that can contaminate a weld and cause porosity? ​

Question 9

What is the difference between spherical porosity and cylindrical porosity? ​

Question 10

A _____ is anything that is not exactly like its surroundings. ​

A)defect​
B)discontinuity​
C)flaw​
D)weld pool​

Question 11

Why may weld testing be delayed for a week or so? ​

Question 12

Cylindrical porosity is often called a _____. ​

Question 13

_____ become defects when they accidentally occur outside the weld groove. ​

Question 14

_____ is when one weld pass does not melt the surface of a previous weld pass. ​

A)Incomplete fusion​
B)Inadequate joint penetration ​
C)Improper joint fit-up ​
D)Inadequate agitation ​

Question 15

_____ is an area of depression of the face or root of a weld where the filler metal did not completely fill the weld groove, so it is level with the surface of the pipe. ​

Question 16

Why can't the bubbles that make up porosity be seen? ​

Question 17

Name the four common causes of weld inclusions. ​

Question 18

Inclusions can be grouped into two major types: linear slag inclusions and _____ inclusions. ​

A)porosity​
B)joint penetration​
C)uniform​
D)scattered​

Question 19

There are _____ major causes of incomplete fusion in pipe welding. ​

A)two​
B)three​
C)four​
D)five​

Question 20

On a fillet weld, underfill occurs when the face of the weld is more _____ than the code. ​

A)flat​
B)concave​
C)convex​
D)laminated​