Schedule (Sch 40 / Sch 80)
/glossary/scheduleWall thickness designation indicating pressure rating and pipe strength classes.
In detail
Schedule (Sch) is a standardized wall thickness designation for pipes that correlates directly with pressure rating. Common schedules include Sch 40 (standard weight), Sch 80 (extra-strong), Sch 160 (double extra-strong), and Sch XXS. Higher schedule numbers indicate thicker walls and higher pressure capacity for the same nominal pipe size. For example, a 2" NB Sch 40 pipe has 3.91 mm wall thickness while Sch 80 has 5.54 mm, significantly increasing pressure rating.
Where you'll meet this in procurement
You will meet Schedule (Sch 40 / Sch 80) on size charts, mill quotes, and fitment checks. Cross-check Schedule (Sch 40 / Sch 80) against OD, wall thickness or schedule, length, and end finish so the delivered pipe matches flanges, fittings, and pressure duty—not just a familiar nominal label.