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Schedule Number
A designation system (SCH 5S, 10S, 40, 80, 160, XXS) that defines the wall thickness of a pipe for a given NPS, with higher schedule numbers indicating thicker walls and higher pressure ratings.
Pipe Schedule System
The schedule number system was introduced by ANSI/ASME to standardize pipe wall thicknesses. For stainless steel pipes, 'S' suffix schedules (5S, 10S, 40S, 80S) are commonly used per ASME B36.19M.
Common Schedules
- SCH 5S/10S — Light wall, low pressure
- SCH 40S — Standard wall, general purpose
- SCH 80S — Extra heavy wall
- SCH 160 — Very high pressure
- XXS — Double extra strong