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Eastern Steel Manufacturing Co.,Ltd is a leading manufacturer and distributor of seamless steel pipe, welded steel pipe, OCTG products and fittings. We supply first-step processing, semi-finished parts and finished parts to help our clients meet fabrication requirements beyond their capacity or to improve operations by moving forward the pre-production processing.
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Eastern Steel Manufacturing Co.,Ltd not only improve product production and sales services, but also provide additional value-added services. As long as you need, we can complete your specific needs together.
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1. What Is Schedule 80 Seamless Steel Pipe?
Schedule 80 seamless steel pipe is manufactured to the Schedule 80 wall-thickness designation for a specified nominal pipe size (NPS). The term “Schedule 80” describes the pipe’s wall thickness; it does not identify the steel grade, material, or a fixed pressure rating. For each NPS, the outside diameter is standardized, while the corresponding Schedule 80 wall thickness changes with pipe size. For example, a 2-inch (NPS 2) Schedule 80 pipe has an outside diameter of 60.3 mm and a nominal wall thickness of 5.54 mm.
Schedule 80 pipe dimensions vary by NPS. For a broader comparison of seamless pipe outside diameter, wall thickness and standard size ranges, see our Seamless Steel Pipe Sizes guide.
| NPS | DN | OD (in.) | OD (mm) | WT (in.) | WT (mm) | Nominal ID (mm) | Weight (lb/ft) | Weight (kg/m) |
|---|---|---|---|---|---|---|---|---|
| 1/8 | DN6 | 0.405 | 10.3 | 0.095 | 2.41 | 5.48 | 0.31 | 0.47 |
| 1/4 | DN8 | 0.54 | 13.7 | 0.119 | 3.02 | 7.66 | 0.54 | 0.8 |
| 3/8 | DN10 | 0.675 | 17.1 | 0.126 | 3.2 | 10.7 | 0.74 | 1.1 |
| 1/2 | DN15 | 0.84 | 21.3 | 0.147 | 3.73 | 13.84 | 1.09 | 1.62 |
| 3/4 | DN20 | 1.05 | 26.7 | 0.154 | 3.91 | 18.88 | 1.47 | 2.2 |
| 1 | DN25 | 1.315 | 33.4 | 0.179 | 4.55 | 24.3 | 2.17 | 3.24 |
| 1 1/4 | DN32 | 1.66 | 42.2 | 0.191 | 4.85 | 32.5 | 3 | 4.47 |
| 1 1/2 | DN40 | 1.9 | 48.3 | 0.2 | 5.08 | 38.14 | 3.63 | 5.41 |
| 2 | DN50 | 2.375 | 60.3 | 0.218 | 5.54 | 49.22 | 5.02 | 7.48 |
| 2 1/2 | DN65 | 2.875 | 73 | 0.276 | 7.01 | 58.98 | 7.66 | 11.41 |
| 3 | DN80 | 3.5 | 88.9 | 0.3 | 7.62 | 73.66 | 10.25 | 15.27 |
| 3 1/2 | DN90 | 4 | 101.6 | 0.318 | 8.08 | 85.44 | 12.51 | 18.63 |
| 4 | DN100 | 4.5 | 114.3 | 0.337 | 8.56 | 97.18 | 14.98 | 22.32 |
| 5 | DN125 | 5.563 | 141.3 | 0.375 | 9.53 | 122.24 | 20.78 | 30.97 |
| 6 | DN150 | 6.625 | 168.3 | 0.432 | 10.97 | 146.36 | 28.57 | 42.56 |
| 8 | DN200 | 8.625 | 219.1 | 0.5 | 12.7 | 193.7 | 43.39 | 64.64 |
| 10 | DN250 | 10.75 | 273.1 | 0.594 | 15.09 | 242.92 | 64.43 | 96.01 |
| 12 | DN300 | 12.75 | 323.9 | 0.688 | 17.48 | 288.94 | 88.63 | 132.04 |
| 14 | DN350 | 14 | 355.6 | 0.75 | 19.05 | 317.5 | 106.13 | 158.1 |
| 16 | DN400 | 16 | 406.4 | 0.844 | 21.44 | 363.52 | 136.61 | 203.53 |
| 18 | DN450 | 18 | 457.2 | 0.938 | 23.83 | 409.54 | 170.92 | 254.55 |
| 20 | DN500 | 20 | 508 | 1.031 | 26.19 | 455.62 | 208.87 | 311.17 |
| 24 | DN600 | 24 | 609.6 | 1.218 | 30.96 | 547.72 | 296.58 | 441.80 |
Note: Nominal inside diameter (ID) is calculated as OD − 2 × nominal wall thickness. Actual dimensions may vary within the applicable manufacturing tolerances. Nominal pipe weight is calculated from standard pipe dimensions.
Schedule 80 seamless steel pipe can be manufactured from carbon steel, stainless steel, or alloy steel according to the applicable product specification and service requirements. The material grade and manufacturing standard must therefore be specified separately from the Schedule designation.
| Material | Common Specification | Typical Grades | Main Selection Consideration |
|---|---|---|---|
| Carbon steel | ASTM A106 / ASTM A53 | Grade B | General and elevated-temperature service |
| Stainless steel | ASTM A312 | TP304/304L, TP316/316L | Corrosion resistance |
| Alloy steel | ASTM A335 | P11, P22, P91 | High-temperature strength |
Schedule 80 seamless pipe is used where the specified wall thickness, material grade, and design requirements are suitable for the service conditions. Common applications include:
1) Process piping: Liquids, gases, and other industrial media.
2) Oil and gas: Process lines and fluid-transfer systems.
3) Steam and elevated-temperature service: Steam and high-temperature piping using suitable carbon or alloy steel grades.
4) Mechanical and industrial systems: Piping and components requiring the specified wall thickness and material properties.
Schedule 80 and XS (Extra Strong) are different pipe wall-thickness designations. They correspond to the same nominal wall thickness in some NPS sizes, while the specified wall thickness differs in others.
Example: For NPS 2 (DN50), Schedule 80 has a nominal wall thickness of 5.54 mm, while XS is 5.54 mm. For other nominal sizes, SCH 80 and XS may have different wall thicknesses.
SCH 80 and XS should not be treated as interchangeable designations without checking the applicable NPS and dimensional standard.
Q1. What is Schedule 80 pipe?
Schedule 80 pipe is a pipe manufactured to the Schedule 80 wall-thickness designation for a specified nominal pipe size (NPS). It defines the nominal wall thickness and does not specify the pipe material or pressure rating.
Q2. What is the pressure rating of Schedule 80 pipe?
Schedule 80 pipe does not have a fixed pressure rating. The allowable pressure depends on pipe size, wall thickness, material grade, temperature, and design requirements.
Q3. How thick is Schedule 80 pipe?
Schedule 80 wall thickness varies by nominal pipe size (NPS). For example, a 1-inch Schedule 80 pipe has a nominal wall thickness of 4.55 mm (0.179 in.), a 2-inch pipe has 5.54 mm (0.218 in.), and a 4-inch pipe has 8.56 mm (0.337 in.).
Q4. Is Schedule 80 a material grade?
No. Schedule 80 is a dimensional designation for pipe wall thickness, not a material grade. Schedule 80 seamless pipe can be manufactured in carbon steel, stainless steel, or alloy steel according to the applicable product specification.
Q5. What is the OD of Schedule 80 pipe?
The outside diameter (OD) of Schedule 80 pipe is determined by the nominal pipe size (NPS), not by the Schedule number. For example, NPS 2 Schedule 80 pipe has an OD of 60.3 mm (2.375 in.), while NPS 4 has an OD of 114.3 mm (4.500 in.).
Q6. Is Schedule 80 pipe seamless?
No. Schedule 80 defines the pipe wall thickness, not the manufacturing method. Both seamless and welded steel pipes can be supplied in Schedule 80 dimensions; the manufacturing type and applicable material specification must be specified separately.
Q7. What is the difference between SCH 80 and XS pipe?
SCH 80 and XS (Extra Strong) are different wall-thickness designations. They have the same nominal wall thickness for some NPS sizes, but not across the full size range, so the applicable NPS and dimensional standard should be checked before substitution.
Seamless Steel Pipe Sizes & Dimensions
E-mail: sales@eastern-steels.com
