This reference page brings together the key dimensional data for 20 inch Schedule 40 pipe, also identified as NPS 20 and DN500. Use the table for a quick check during piping layout, material takeoff, fabrication planning, and CAD drafting.
The listed values are useful for identifying the pipe section and coordinating related components. For connected items, see the site’s references for pipe fittings, pipe flanges, and pipe schedules.
Schedule 40 pipe 20 inch (DN500) is a standard steel pipe size commonly used in piping design, fabrication, drafting, and engineering estimation work. This page provides the standard dimensions and weight data for NPS 20 Schedule 40 pipe based on ANSI / ASME B36.10, including outside diameter, inside diameter, wall thickness, and weight per meter.
This size is widely used in industrial piping systems, water lines, utility services, and fabrication projects where accurate dimensional data is important for layout, support design, material takeoff, and installation planning.
20 Inch Schedule 40 Pipe Dimensions
- Nominal Pipe Size (NPS): 20 inch
- Diameter Nominal (DN): DN500
- Pipe Schedule: Schedule 40
- Outside Diameter (OD): 508 mm
- Wall Thickness: 15.09 mm
- Inside Diameter (ID): 477.82 mm
- Pipe Weight: 183.43 kg/m
- Pipe Weight Including Water: 362.65 kg/m
- Reference Standard: ANSI / ASME B36.10
Schedule 40 Pipe 20 Inch (DN500) Data Table
| NPS | DN | OD (mm) | Wall Thickness (mm) | ID (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 20 inch | DN500 | 508 | 15.09 | 477.82 | 183.43 |
What Is 20 Inch Schedule 40 Pipe Used For?
20 inch Schedule 40 pipe is commonly used in medium to large industrial and utility piping systems where a standardized steel pipe size is required. Engineers, designers, and fabricators often use this size in:
- Water transmission and distribution systems
- Cooling water piping
- Industrial utility lines
- Process piping systems
- Plant layout and pipe routing work
- Fabrication and spool drawing preparation
Because this is a substantial pipe size, accurate dimensions and weight data are important for support design, transport planning, lifting studies, and material estimation.
Why These Dimensions Matter in Engineering
In piping and mechanical design, standard pipe dimensions are important for more than simple identification. The outside diameter is used for supports, clamps, insulation sizing, and equipment connection layouts. The inside diameter affects internal flow area and hydraulic calculations. The wall thickness is important for fabrication, welding preparation, and pipe strength, while the pipe weight per meter is essential for support load calculations and installation planning.
Using the correct DN500 Schedule 40 pipe dimensions helps reduce drafting errors, procurement mistakes, and field fit-up problems during construction and fabrication work.
20 Inch DN500 Schedule 40 Pipe for CAD and Drafting Work
For CAD, BIM, and piping drafting work, this size is commonly listed as NPS 20 or DN500. The standard OD of 508 mm is especially useful for routing clearance, support detailing, and nozzle or equipment connection references in both 2D drawings and 3D models.
This page can be used as a quick reference for 20 inch Schedule 40 pipe dimensions, DN500 pipe dimensions, and Schedule 40 steel pipe weight per meter during design, drafting, and estimation work.
Frequently Asked Questions
What is the outside diameter of 20 inch Schedule 40 pipe?
The outside diameter of 20 inch Schedule 40 pipe is 508 mm.
What is the wall thickness of DN500 Schedule 40 pipe?
The wall thickness is 15.09 mm.
What is the inside diameter of Schedule 40 pipe 20 inch?
The inside diameter is 477.82 mm.
How much does 20 inch Schedule 40 pipe weigh?
The pipe weight is 183.43 kg/m. The weight including water is 362.65 kg/m.
Which standard covers these dimensions?
These dimensions are based on ANSI / ASME B36.10.
Conclusion
Schedule 40 pipe 20 inch (DN500) is an important reference size for industrial piping, drafting, fabrication, and engineering calculations. With an OD of 508 mm, ID of 477.82 mm, wall thickness of 15.09 mm, and weight of 183.43 kg/m, it is a useful standard pipe size for engineers, designers, and estimators working with steel piping systems.
For more pipe schedule data, compare this size with nearby standard sizes such as 18 inch and 24 inch Schedule 40 pipe pages.
How to Use This 20 Inch Pipe Reference
Start with the nominal designation when searching specifications or selecting a catalog item: NPS 20 is the inch-based designation, while DN500 is the metric designation used in many drawings and equipment records. These labels identify the nominal pipe size; they should not be treated as a direct measurement of the actual outside or inside diameter.
For layout work, the outside diameter is the primary dimensional reference for pipe routing, support interfaces, clamps, insulation space, and openings. The inside diameter is the relevant listed dimension for checking the available internal passage and coordinating hydraulic or process calculations. The wall thickness identifies the selected schedule and is important when reviewing fabrication details, end preparations, and connected components.
Design and Drafting Checks
- Use the outside diameter when checking physical clearance and support geometry.
- Use the inside diameter only as the listed reference dimension for flow or process calculations; verify the applicable design basis separately.
- Use the pipe weight per meter when preparing preliminary support, lifting, transport, and material-estimate information.
- Confirm the material grade, manufacturing requirements, corrosion allowance, operating conditions, and project specification before design approval or procurement.
- Coordinate this pipe data with the dimensions of matching fittings, flanges, valves, and equipment nozzles.
CAD and DWG Reference
The accompanying DWG resource can help with initial 2D drafting and layout coordination. Before using a drawing in a construction package, check the drawing units, layer conventions, connection details, clearances, and project-specific dimensional requirements. A CAD reference should support engineering review rather than replace the applicable piping specification or approved design documents.
Related Pipe Dimension Resources
For comparison work, link this page with the site’s references for pipe dimensions, Schedule 40 pipe, and nearby nominal sizes. These related pages help readers compare standard sections without confusing nominal size, schedule, outside diameter, and wall thickness.
Practical Questions About This Reference
Is NPS 20 the same designation as DN500?
They are the inch-based and metric nominal designations used to identify this pipe size. The actual dimensional values should be taken from the listed data rather than inferred from the nominal labels.
Which dimension should be used for a pipe support layout?
Use the listed outside diameter for the physical pipe envelope and coordinate it with the support, clamp, guide, insulation, and clearance requirements shown in the project documents.
Can the listed pipe weight be used as a final support load?
The listed weight is a useful reference for estimation and preliminary coordination. Final support design should also account for the project’s contents, insulation, fittings, valves, operating conditions, load combinations, and applicable engineering requirements.
Can the DWG file be used directly for fabrication?
Use the DWG as a drafting reference and verify units, dimensions, connections, tolerances, and project-specific requirements before issuing fabrication or construction documents.