Qualification of pipes

Question 1

Standard for failure

Answer 1

Current standards usually stipulate that there should be no transition from ductile to brittle failure within 10,000 hours at higher temperatures (60 or 80 degrees)

Question 2

MRS

Answer 2

Minimum recommended stress - The hoop stress for a 50yr life at 20 degrees, from extrapolation from the LCL

Question 3

LCL

Answer 3

The lower confidence limit for a material is the level, usually 97.5%, in which you can be confident that the material would not fail.