B31.3, B31.4 or B31.8: Which Code Governs Your Line?
Plant piping, liquid pipelines and gas pipelines each have their own ASME code. Here is where one ends and the next begins, and why the boundary matters.
Topic
Codes & Standards
ASME B31.3, B31.4, B31.8, API, NORSOK and DNV explained.
B31.3 Fluid Service Categories: Normal, Category D, Category M and High Pressure
The fluid service category decides how much examination and testing a line gets. Picking the wrong one either wastes money or leaves a real hazard under-inspected.
Piping Material Specifications and Line Classes: How a Spec Is Built
Every line on a P&ID points to a piping class. Here is what sits inside that class and how to read one without getting lost.
API 5L Line Pipe: PSL1 vs PSL2 Explained
API 5L pipe comes in two product specification levels. PSL2 adds toughness testing, tighter chemistry and more control, and many projects require it by default.
NORSOK and DNV: The Standards Behind North Sea and Offshore Piping
Offshore projects add a layer of NORSOK and DNV standards on top of ASME. Here are the ones a piping engineer meets most often and what each one controls.