Brittle Fracture assessment
Brittle Fracture assessment
(OP)
I am asked to evaluate an existing vessel that has seem many years of service for brittle fracture. The minimum design metal temperature is not changing.
I am not sure if it is required to be done because I have researched this topic a bit and it is advised in API-653 (5.2.2) that brittle fracture is a concern for initial testing of a low temperature vessel, re-rating, or reconstruction - none of which are expected.
If an analysis were to be done for brittle fracture, what is the applicable guideline? Is it API-653 or API-579, as I am not familiar with these standards and their applicability and if they overlap on the issue of brittle fracture.
I am not sure if it is required to be done because I have researched this topic a bit and it is advised in API-653 (5.2.2) that brittle fracture is a concern for initial testing of a low temperature vessel, re-rating, or reconstruction - none of which are expected.
If an analysis were to be done for brittle fracture, what is the applicable guideline? Is it API-653 or API-579, as I am not familiar with these standards and their applicability and if they overlap on the issue of brittle fracture.





RE: Brittle Fracture assessment
Look up in 650 what the temperature zone that tank is in.
If zone > material MDMT, you are done. Write a memo documenting your findings.
Some times our job really is that simple.
RE: Brittle Fracture assessment
I'm still interested to know when to apply API-653 and API-579 and if they overlap in terms of brittle assessment.
RE: Brittle Fracture assessment
FYI - Brittle Fracture is one of the few Catastrophic failure mechanisms. Usually tanks & vessels just leak. With Brittle Fracture, there can be the Big Boom that destroys plants and adjacent communities. Insurance carriers always want to know about any Catastrophic failure mechanisms; probably why your investigation is being done.
RE: Brittle Fracture assessment