Use this page as a practical reference when identifying, modeling, estimating, or detailing Schedule 40 pipe 1 1/4 inch (DN32). The source table provides the dimensional and weight data needed to coordinate pipe routing, supports, fittings, and fabrication drawings.
For accurate project work, distinguish the nominal pipe designation from the measured geometry. NPS 1 1/4 and DN32 identify the standardized pipe size, while the listed outside diameter, inside diameter, and wall thickness should be used for layout and checking. The downloadable DWG is useful when this reference needs to be transferred into a CAD workflow.
Schedule 40 pipe 1 1/4 inch (DN32) 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 1 1/4 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.
1 1/4 Inch Schedule 40 Pipe Dimensions
- Nominal Pipe Size (NPS): 1 1/4 inch
- Diameter Nominal (DN): DN32
- Pipe Schedule: Schedule 40
- Outside Diameter (OD): 42.2 mm
- Wall Thickness: 3.56 mm
- Inside Diameter (ID): 35.08 mm
- Pipe Weight: 3.39 kg/m
- Pipe Weight Including Water: 4.35 kg/m
- Reference Standard: ANSI / ASME B36.10
Schedule 40 Pipe 1 1/4 Inch (DN32) Data Table
| NPS | DN | OD (mm) | Wall Thickness (mm) | ID (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 1 1/4 inch | DN32 | 42.2 | 3.56 | 35.08 | 3.39 |
What Is 1 1/4 Inch Schedule 40 Pipe Used For?
1 1/4 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 distribution systems, cooling water piping, industrial utility lines, process piping systems, mechanical piping layouts, and fabrication work.
Because this is a practical and widely used pipe size, accurate dimensions and weight data are important for support design, installation work, material estimation, and field coordination.
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 DN32 Schedule 40 pipe dimensions helps reduce drafting errors, procurement mistakes, and field fit-up problems during construction and fabrication work.
1 1/4 Inch DN32 Schedule 40 Pipe for CAD and Drafting Work
For CAD, BIM, and piping drafting work, this size is commonly listed as NPS 1 1/4 or DN32. The standard OD of 42.2 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 1 1/4 inch Schedule 40 pipe dimensions, DN32 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 1 1/4 inch Schedule 40 pipe?
The outside diameter of 1 1/4 inch Schedule 40 pipe is 42.2 mm.
What is the wall thickness of DN32 Schedule 40 pipe?
The wall thickness is 3.56 mm.
What is the inside diameter of Schedule 40 pipe 1 1/4 inch?
The inside diameter is 35.08 mm.
How much does 1 1/4 inch Schedule 40 pipe weigh?
The pipe weight is 3.39 kg/m. The weight including water is 4.35 kg/m.
Which standard covers these dimensions?
These dimensions are based on ANSI / ASME B36.10.
Conclusion
Schedule 40 pipe 1 1/4 inch (DN32) is an important reference size for industrial piping, drafting, fabrication, and engineering calculations. With an OD of 42.2 mm, ID of 35.08 mm, wall thickness of 3.56 mm, and weight of 3.39 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 1 inch and 1 1/2 inch Schedule 40 pipe pages.
How to Use This DN32 Schedule 40 Reference
The dimension table is most useful when several disciplines need the same pipe definition. Designers can use the outside diameter for spatial coordination and connection layouts, while drafters can use the dimensional data to check clearances, supports, clamps, and model geometry. Fabricators can use the wall-thickness entry as a reference when reviewing details, weld preparation, and fit-up information.
The inside diameter is the relevant geometric value for evaluating the available internal passage. Any flow, pressure-loss, or process calculation should still use the applicable project conditions, fluid properties, fittings, and engineering requirements rather than relying on the nominal size alone.
Pipe Weight and Installation Planning
The listed pipe weight per meter supports preliminary material takeoffs, handling reviews, and support-load estimates. The separate value including water is useful for recognizing that an operating or filled line can impose a different load from the bare pipe. Final support and structural checks may also need to account for contents, insulation, coatings, valves, fittings, testing conditions, and local design requirements.
CAD, DWG, and Related Pipe References
When building a 2D detail or 3D piping model, use the listed outside diameter for the pipe envelope and verify that connected fittings, flanges, valves, and equipment nozzles use compatible dimensional references. The downloadable Schedule 40 Pipe 1 1/4 Inch DN32 DWG can help establish a consistent starting geometry, but project models should be checked against the selected component and connection details.
For comparison work, link this page with the site’s related Schedule 40 pipe dimensions, pipe schedule reference, steel pipe weight, pipe fittings, and flange dimensions resources. Nearby NPS sizes, including the referenced 1 inch and 1 1/2 inch pages, are useful for checking routing transitions and material selections.
Additional Questions About NPS 1 1/4 Schedule 40 Pipe
Does the nominal size equal the measured outside diameter?
No. The nominal designation identifies a standardized pipe size; it is not a direct statement of the measured outside diameter. Use the outside diameter listed in the reference data for CAD, supports, and connection coordination.
Which dimension should be used for a pipe clearance check?
Use the outside diameter for the basic pipe envelope, then allow for any applicable insulation, coating, clamp, support, or neighboring-component requirements. The project drawing and equipment details control the final clearance.
Can the listed pipe weight be used as the final support load?
It can support preliminary estimating and coordination, but it should not automatically be treated as the complete design load. Check whether the installation includes fluid, insulation, fittings, valves, test contents, and other supported components.
Is the DWG file a substitute for a project fabrication drawing?
No. The DWG is a reference resource for drafting and modeling. Confirm interfaces, tolerances, component dimensions, materials, and project-specific requirements before issuing fabrication or construction documents.