Schedule 40 Stainless Steel Pipe Dimensions

Stainless steel pipe (SS Pipe) is widely used in industries requiring corrosion resistance, hygiene, and durability—such as chemical processing, food and beverage, pharmaceuticals, and oil and gas. Schedule 40S is the standard wall thickness series for stainless steel pipes as defined by ASME B36.19, where the “S” suffix distinguishes stainless steel schedules from carbon steel schedules (ASME B36.10).

What is a Schedule 40S  Pipe?

The schedule number indicates the wall thickness of a pipe. For a given NPS (Nominal Pipe Size), the outside diameter remains constant, while the wall thickness increases with higher schedule numbers. Schedule 40S is commonly used for general corrosive service and moderate-pressure applications.

It is important to note that for NPS 8 and smaller, Schedule 40S wall thickness matches carbon steel Schedule 40. However, for NPS 10 and above, Schedule 40S is thinner than Schedule 40—this is why the “S” suffix must be specified when ordering stainless steel pipe.

Schedule 40S Stainless Steel Pipe Dimensions – Metric (mm) with Weight

The table below provides complete dimensional data for Schedule 40S stainless steel pipes per ASME B36.19, covering NPS 1/8 to NPS 24.

Schedule 40S Stainless Steel Pipe Dimensions – Imperial (inches) with Weight

For reference, here are the same dimensions in imperial units.

Applications:

Schedule 40S stainless steel pipes are commonly used in:

● Chemical and petrochemical processing – corrosion-resistant fluid transmission
● Food and beverage industry – sanitary piping systems
● Pharmaceutical manufacturing – clean, non-contaminating process lines
● Water and wastewater treatment –Corrosion-resistant piping systems

Material Grades:

Schedule 40S stainless steel pipes are available in common grades such as 304/304L and 316/316L, and are typically manufactured to ASTM A312 for seamless and welded pipe, with finishes including annealed and pickled.

Standards Reference:

ASME B36.19 – Stainless steel pipe dimensions and wall thickness
ASTM A312 – Standard specification for seamless and welded stainless steel pipe

For precise pipe sizes and custom specifications, contact our technical sales team: sales@hu-steel.com