Use this reference when checking 16 inch Schedule 40 pipe dimensions for piping layouts, material takeoffs, fabrication documents, support studies, and CAD models. The existing data below provides the authoritative local values for NPS 16 and DN400, while the accompanying notes explain how to apply each dimension during engineering and drafting work.
Schedule 40 pipe 16 inch (DN400) 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 16 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, utility services, water lines, and fabrication projects where accurate dimensional data is important for layout, support design, material takeoff, and installation planning.
16 Inch Schedule 40 Pipe Dimensions
- Nominal Pipe Size (NPS): 16 inch
- Diameter Nominal (DN): DN400
- Pipe Schedule: Schedule 40
- Outside Diameter (OD): 406.4 mm
- Wall Thickness: 12.7 mm
- Inside Diameter (ID): 381 mm
- Pipe Weight: 123.31 kg/m
- Pipe Weight Including Water: 237.26 kg/m
- Reference Standard: ANSI / ASME B36.10
Schedule 40 Pipe 16 Inch (DN400) Data Table
| NPS | DN | OD (mm) | Wall Thickness (mm) | ID (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 16 inch | DN400 | 406.4 | 12.7 | 381 | 123.31 |
What Is 16 Inch Schedule 40 Pipe Used For?
16 inch Schedule 40 pipe is commonly used in 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 DN400 Schedule 40 pipe dimensions helps reduce drafting errors, procurement mistakes, and field fit-up problems during construction and fabrication work.
16 Inch DN400 Schedule 40 Pipe for CAD and Drafting Work
For CAD, BIM, and piping drafting work, this size is commonly listed as NPS 16 or DN400. The standard OD of 406.4 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 16 inch Schedule 40 pipe dimensions, DN400 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 16 inch Schedule 40 pipe?
The outside diameter of 16 inch Schedule 40 pipe is 406.4 mm.
What is the wall thickness of DN400 Schedule 40 pipe?
The wall thickness is 12.7 mm.
What is the inside diameter of Schedule 40 pipe 16 inch?
The inside diameter is 381 mm.
How much does 16 inch Schedule 40 pipe weigh?
The pipe weight is 123.31 kg/m. The weight including water is 237.26 kg/m.
Which standard covers these dimensions?
These dimensions are based on ANSI / ASME B36.10.
Conclusion
Schedule 40 pipe 16 inch (DN400) is an important reference size for industrial piping, drafting, fabrication, and engineering calculations. With an OD of 406.4 mm, ID of 381 mm, wall thickness of 12.7 mm, and weight of 123.31 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 14 inch and 18 inch Schedule 40 pipe pages.
How to Read This Pipe Reference
NPS 16 and DN400 identify the same nominal pipe size using two different designation systems. The nominal designation should not be treated as the measured outside diameter. For layout and connection work, use the listed outside diameter; for internal flow or clearance checks, use the listed inside diameter.
The schedule is a standardized wall-thickness designation for the pipe size. It is not a material grade, pressure rating, or complete design specification. Final selection still requires verification of the material, service conditions, applicable piping code, corrosion allowance, joining method, and project requirements.
Practical Checks Before Using the Values
- Use the outside diameter when checking pipe routing, clamps, supports, insulation space, and equipment connection geometry.
- Use the inside diameter when preparing flow-area, hydraulic, or internal-clearance calculations.
- Use wall thickness for fabrication references and dimensional checks, but do not treat it alone as proof of pressure suitability.
- Use the listed mass per meter for preliminary estimating and support-load studies, then account for contents, insulation, fittings, valves, and project-specific requirements where applicable.
- Confirm whether a drawing or procurement document requires NPS, DN, outside diameter, schedule, material grade, or all of these identifiers.
Related Pipe and Drafting References
For broader design and drafting work, connect this page to the site’s references for pipe schedules, NPS and DN terminology, pipe fittings, flange dimensions, and CAD/DWG piping resources. A comparison with the nearby 14 inch and 18 inch Schedule 40 references can also help users review size changes without confusing nominal size with outside diameter.
When transferring this information into a CAD or BIM model, keep the pipe designation, outside diameter, wall thickness, and material specification as separate properties. This makes the model easier to review and reduces the risk of using a nominal label as a geometric value.
Additional Reference Questions
Is NPS 16 the same nominal size as DN400?
Yes. In this reference, NPS 16 and DN400 identify the same nominal pipe size. Use the dimensional values in the table for geometry rather than assuming the nominal label is the measured outside diameter.
Does Schedule 40 identify the pipe material grade?
No. Schedule 40 describes the standardized dimensional designation used for this pipe size. The material grade, manufacturing requirements, corrosion allowance, and design suitability must be confirmed separately.
Which dimension is most important for CAD routing?
The outside diameter is the primary dimensional reference for routing envelopes, supports, clamps, insulation coordination, and connection layouts. The inside diameter and wall thickness remain important for internal calculations and fabrication documentation.
Can the listed weight including water be used as the final support load?
It is a useful reference value, but a final support load assessment should also consider the actual contents, insulation, fittings, valves, test conditions, support arrangement, and applicable project criteria.