What is a pipe schedule?
Pipe Gauge (SCH) is a measure of the nominal wall thickness of steel pipe.
What is Schedule 40?
Schedule 40 (SCH 40) carbon steel pipe is a type of pipe specification that represents the pipe's wall thickness and pressure-bearing capacity.
The wall thickness of SCH 40 pipe is: 40×1/1000=0.040 inches=1.016 mm.
According to the American pipeline standard ANSI/ASME B36.10M, the specific specifications of SCH 40 steel pipe are:
Outside diameter: 1/8 inch ~ 30 inches, wide range, covering various pipeline applications.
Wall thickness: 0.040 inches, approximately 1.016 mm.
Nominal diameter ratio: 0.85 (D/t).
The minimum yield strength specified by the standard: 35000PSI or 240Mpa.
Standard working pressure: up to 700PSI, about 48.3Bar.
What is Schedule 80?
Schedule 80 (SCH 80) carbon steel pipe is also a type of pipe specification, which means the pipe has thicker wall thickness and higher pressure-bearing capacity.
The wall thickness of SCH 80 pipe is 80×1/1000=0.080 inches=2.032 mm, which is twice the wall thickness of SCH 40.
According to the American pipeline standard ANSI/ASME B36.10M, the specific specifications of SCH 80 steel pipe are:
Outside diameter: 1/8 inch ~ 30 inches, same range as SCH40, but wider.
Wall thickness: 0.080 inches, about 2.032 mm, 2 times that of SCH40.
Nominal diameter ratio: 0.43 (D/t).
The minimum yield strength specified by the standard: 35000PSI or 240Mpa, the same as SCH 40.
Standard working pressure: up to 3000PSI, about 207Bar, much higher than SCH 40.
Schedule 40 and Schedule 80 pipelines:
1. Wall Thickness - Schedule 80 pipe has a thicker wall than Schedule 40 pipe for the same NPS. The increased wall thickness makes Schedule 80 pipe stronger and able to withstand higher pressures and heavier loads.
2. Weight - The weight of Schedule 40 pipe depends on its length and material composition, but it is lighter than Schedule 80 pipe due to its thinner walls.
3. Pressure Rating - Schedule 40 pipe has a lower pressure rating than Schedule 80 pipe due to its relatively thinner wall thickness.
4. Schedule 80 pipe can withstand higher pressures and is typically used in heavy-duty applications.
