Steel pipes with an outer diameter to wall thickness ratio of less than 20 are called heavy wall steel pipes. Due to their larger wall thickness, these steel pipes have higher pressure resistance, deformation resistance and structural stability, and are widely used in high-intensity working conditions.
Custom Heavy-Wall Solutions: From Sch 160 to XXS – We Supply Precision Specs.
Heavy-Wall Steel Pipe Dimension Table
| Nominal Pipe Size (NPS - inch) | Outside Diameter (OD - mm) | Sch 80 (Heavy - mm) | Sch 160 (Extra Heavy - mm) | XXS (Double Extra Strong - mm) |
| 2" | 60.33 | 5.54 | 8.74 | 11.07 |
| 3" | 88.90 | 7.62 | 11.13 | 15.24 |
| 4" | 114.30 | 8.56 | 13.49 | 17.12 |
| 5" | 141.30 | 9.53 | 15.88 | 19.05 |
| 6" | 168.28 | 10.97 | 18.26 | 21.95 |
| 8" | 219.08 | 12.70 | 23.01 | 22.23 |
| 10" | 273.05 | 15.09 | 28.58 | 25.40 |
| 12" | 323.85 | 17.48 | 33.32 | 25.40 |
Standards for Heavy-Wall Steel Pipe
| Industry Sector | Standard / Specification | Description |
| Oil & Gas (OCTG) | API 5CT | Specification for Casing and Tubing: Heavy-wall casing for deep and high-pressure wells. |
| API 5L | Specification for Line Pipe: High-pressure oil and gas transmission lines. | |
| General Purpose / Fluid | ASTM A106 / A53 | Seamless Carbon Steel Pipe for High-Temperature Service: Used in high-pressure fluid transport. |
| DIN 2448 | Seamless Steel Pipes and Tubes: European standard for technical delivery conditions. | |
| Structural & Mechanical | ASTM A519 / A500 | Seamless Carbon and Alloy Steel Mechanical Tubing: Used in heavy-load machinery parts. |
| EN 10210 / 10297 | Hot Finished Structural Hollow Sections: For mechanical and general engineering. | |
| High-Pressure Boilers | ASTM A335 | Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service: Main steam pipes in power plants. |
| ASME SA213 / SA335 | Boiler, Superheater, and Heat-Exchanger Tubes: High-pressure boiler components. | |
| Low-Temperature Service | ASTM A333 | Seamless Pipe for Low-Temperature Service: Used in LNG or arctic environments. |
heavy wall pipe Materials and Steel Grades
Carbon Steel: ASTM A106 Gr.B, ASTM A53 Gr.B, API 5L B, 20#, 45#, S355.
Alloy Steel: 4140, 42CrMo, ASTM A335 P11, P22, P91, API 5CT P110, Q125.
Stainless Steel: 304/304L, 316/316L, 31803 (Duplex), 32750 (Super Duplex).
heavy wall pipe Non-Destructive Testing (NDT)
| NDT Method | Description | Primary Application |
| Ultrasonic Testing (UT) | Top Priority for Heavy-Wall. Penetrates deep steel layers to find internal cracks/lamination. | 100% Full-body automated scanning |
| Magnetic Particle (MPI) | Detects fine surface and near-surface cracks. | Threaded ends, pipe-end processing areas |
| Eddy Current (ET) | Rapidly detects surface point-defects and pits. | In-line monitoring during production |
| Thickness Mapping | Continuous ultrasonic scanning to generate a wall-thickness distribution map. | High-end customized heavy-wall projects |
heavy wall Steel pipe Pressure & Safety Testing
| Test Item | Description |
| Hydrostatic Test | Internal water pressure test based on API/ASTM formulas; held longer for heavy walls. |
| Gas-Tight Leak Test | For premium threaded casing/tubing using Helium or Nitrogen to ensure 100% seal. |
GNEE Heavy wall pipe test and inspection
GNEE heavy wall pipe in stock
FAQ
What is considered heavy wall pipe?
Heavy wall pipe is described as pipe with dimensions equal to or greater than the American Society of Mechanical Engineers (ASME) Schedule 80 pipe. Pipe schedules begin with Schedule 10 pipe. As the schedule number increases so does the thickness of the wall of the pipe.
How thick is Schedule 20 steel pipe?
Schedule 20 Steel Pipe Dimensions :
| Nominal size [inches] | Outside diameter [inches] | Wall thickness [mm] |
|---|---|---|
| 20 inches | 20.000 inches | 9.53 mm |
| 22 inches | 22.000 inches | 9.53 mm |
| 24 inches | 24.000 inches | 9.53 mm |
| 26 inches | 26.000 inches | 12.70 mm |
Which is thicker, schedule 20 or 40?
GI pipe Schedule 40 is the industry standard for heavier-duty applications. It has thicker walls and higher structural strength. The GI pipe Schedule 40 thickness (mm) is greater than that of Schedule 20, allowing it to withstand higher pressure, impact, and load-bearing requirements.
