Use this page as a quick reference for 1 1/4 inch Schedule 5 pipe, also identified as NPS 1 1/4 and DN32. The table below brings together the dimensional and weight information needed for piping layouts, material takeoffs, fabrication planning, and drawing review.
When coordinating this pipe with other components, check the listed outside diameter against the selected pipe fittings, flanges, clamps, supports, and connection details. The downloadable DWG can also help drafters incorporate the referenced pipe geometry into project layouts.
Schedule 5 Pipe 1 1/4 Inch (DN32) is a steel pipe size commonly used in industrial piping systems that require good flow capacity with a relatively light wall thickness. This pipe size is often used in utility piping, water systems, low-pressure industrial service, and general steel pipe fabrication work.
This dimension data is based on ANSI/ASME B36.10, which is the standard commonly used for carbon steel pipe dimensions.
1 1/4 Inch Schedule 5 Pipe Dimensions
- Pipe Schedule: 5
- Nominal Pipe Size: 1 1/4 Inch
- DN Size: DN32
- Outside Diameter (OD): 42.2 mm
- Inside Diameter (ID): 38.9 mm
- Wall Thickness: 1.65 mm
- Pipe Weight: 1.65 kg/m
- Pipe Weight Including Water: 2.83 kg/m
- Standard: ANSI/ASME B36.10
Schedule 5 Pipe 1 1/4 Inch Dimension Table
| Pipe Schedule | NPS (Inch) | DN (mm) | OD (mm) | ID (mm) | Wall Thickness (mm) | Weight (kg/m) |
|---|---|---|---|---|---|---|
| 5 | 1 1/4 | 32 | 42.2 | 38.9 | 1.65 | 1.65 |
What Is 1 1/4 Inch Schedule 5 Pipe?
A 1 1/4 inch Schedule 5 pipe is a steel pipe with a nominal size of 1 1/4 inches and a relatively thin wall thickness compared with heavier schedules. For this size, the outside diameter is fixed at 42.2 mm, while the inside diameter is 38.9 mm based on a wall thickness of 1.65 mm.
Schedule 5 pipe is often selected when a project needs good flow capacity, reduced pipe weight, and easier handling compared with thicker wall pipes. It is commonly referenced in steel piping design, drafting, fabrication, and material takeoff work.
Where Is Schedule 5 Pipe 1 1/4 Inch Used?
This pipe size is commonly used in applications that need good flow capacity with relatively light wall thickness. Typical uses include:
- Water transfer and distribution systems
- Utility and low-pressure industrial piping
- Process and service lines
- Pipe spool fabrication and layout work
- General steel piping projects
Why Pipe Dimensions Matter
Accurate 1 1/4 inch Schedule 5 pipe dimensions are important for piping layout, fabrication, transport planning, support design, and installation work. Engineers and designers often check OD, ID, wall thickness, and weight before selecting supports, fittings, welding details, and handling methods.
The outside diameter is important for matching supports, clamps, and pipe accessories. The inside diameter helps estimate internal flow area and system capacity. The wall thickness affects mechanical strength and specification compliance, while the pipe weight per meter is useful for lifting plans, transport, and structural loading calculations.
1 1/4 Inch Schedule 5 Pipe Weight Information
The nominal weight of this pipe size is 1.65 kg/m. When filled with water, the combined weight becomes approximately 2.83 kg/m. This information is useful for pipe support design, structural coordination, and lifting preparation in piping systems.
Difference Between NPS 1 1/4 and DN32
NPS 1 1/4 is the inch-based nominal pipe size, while DN32 is the metric designation used in international drawings and specifications. Both terms refer to the same nominal pipe size, and users may search by either inch size or DN format depending on project standards.
Common Search Terms for This Pipe Size
Users may also search for this pipe using related keywords such as 1 1/4 inch Schedule 5 pipe dimensions, DN32 Schedule 5 pipe dimensions, 1 1/4 inch pipe weight per meter, DN32 pipe dimensions, or DN32 sch 5 pipe dimensions.
Conclusion
Schedule 5 Pipe 1 1/4 Inch (DN32) has an outside diameter of 42.2 mm, an inside diameter of 38.9 mm, a wall thickness of 1.65 mm, and a weight of 1.65 kg/m. It is a useful steel pipe reference size for design, drafting, fabrication, and procurement work.
This page provides a quick reference for engineers, drafters, fabricators, and buyers who need reliable 1 1/4 inch Schedule 5 pipe dimensions and DN32 pipe dimensions in one place.
How to Use This Pipe Reference
The dimension table is most useful when several project tasks must be checked together. Use the outside diameter for external fit-up and support coordination, the inside diameter for flow-area estimates, and the wall thickness when reviewing fabrication details or comparing this size with other pipe schedules.
The weight information supports preliminary material takeoffs, handling reviews, and coordination with support or structural teams. It should be used alongside the project material specification, design conditions, joining method, corrosion requirements, and applicable engineering checks. A schedule designation by itself should not be treated as a complete design qualification.
Drafting and Procurement Notes
- Confirm whether the project documentation uses the inch-based NPS designation or the metric DN designation.
- Match the pipe outside diameter with the bore and connection details of associated fittings and flanges.
- Use the stated pipe weight for preliminary coordination, then confirm project-specific material and manufacturing requirements before ordering.
- Review the downloadable DWG pipe drawing against the project’s drafting conventions before incorporating it into issued documents.
For broader comparison work, readers may also find related references on NPS and DN pipe sizes, pipe schedule selection, pipe fittings, flange dimensions, and pipe support design useful when developing a complete piping layout.
Frequently Asked Questions
What do NPS 1 1/4 and DN32 mean?
They are two nominal designations for the same pipe size: NPS 1 1/4 uses the inch-based naming system, while DN32 uses the metric designation. The actual dimensional information is provided in the reference table.
Which pipe dimensions are important when selecting fittings?
The outside diameter is important for external fit-up, while the inside diameter and wall thickness help describe the pipe bore and section. Always compare the pipe data with the fitting, flange, and connection specification being used on the project.
Can the listed pipe weight be used for support design?
The listed weight can support preliminary coordination and loading estimates. Final support design should also account for the project installation arrangement, contents, insulation or attachments, support spacing, operating conditions, and applicable engineering requirements.
Is Schedule 5 suitable for every low-pressure application?
No. Application suitability depends on more than the schedule designation. Verify the material specification, design conditions, joining details, corrosion allowance where applicable, and governing project requirements before selecting the pipe.
Is a CAD file available for this pipe reference?
Yes. The page includes a downloadable DWG reference for the listed pipe size. Review the file and confirm its geometry and drafting suitability before using it in production drawings.