Pipeline Materials

Question 1

Define Strength

Answer 1

Pipeline strength specified by its yield strength. Define yield strength as maximum stress material can
withstand before plastic flow

Question 2

Define Proof Stress

Answer 2

Stress to produce specified permanent plastic extension

Question 3

Define Bauschinger effect

Answer 3

When a material is plastically strained in one direction the measured yield strength in the opposite direction is reduced

Question 4

Define Toughness

Answer 4

• The energy to break a unit volume of material (not to be confused with the stress required to break a specimen)
• Related to the area under the stress-strain curve

Question 5

Upper Shelf Energy

Answer 5

Predominantly ductile. The temperature range in which the surface of the specimen exhibits an appearance indicative of a ductile fracture.

Question 6

Lower Shelf Energy

Answer 6

Predominantly brittle. The temperature range in which the surface of the specimen exhibits an appearance indicative of a brittle fracture.

Question 7

Define excessive hardness

Answer 7

The property of the material which enables it to resist plastic deformation, usually by penetration or by indentation. The term of hardness is also referred to stiffness or temper, or to resistance to bending, scratching, abrasion, or cutting.