This reference page is for engineers, designers, estimators, fabricators, and inspectors who need a quick check of 1 inch DN25 Schedule XS pipe. Use the dimension list and table for size verification, while the explanatory notes clarify how nominal size, outside diameter, wall thickness, inside diameter, and weight relate to one another.
For project work, confirm the required material specification, end preparation, corrosion allowance, joining method, and design conditions separately. The dimensions shown here support drafting and coordination; they should not replace project specifications or engineering review.
Schedule XS Pipe 1 Inch (DN25) is a steel pipe size commonly used in industrial piping systems, utility lines, water transmission projects, plant construction, and fabrication work. This page provides a practical reference for the main dimensions and weight of 1 inch XS pipe based on ANSI/ASME B36.10.
For piping engineers, CAD designers, estimators, fabrication teams, and site supervisors, accurate pipe size data is important for layout work, material takeoff, support design, transport planning, and installation checks. This guide presents the essential dimensions in a cleaner format that adds more value than a simple size table.
1 Inch Schedule XS Pipe Dimensions
- Pipe Size: 1 Inch
- Nominal Diameter: DN25
- Pipe Schedule: XS (Extra Strong)
- Outside Diameter (OD): 33.4 mm
- Inside Diameter (ID): 24.3 mm
- Wall Thickness: 4.55 mm
- Pipe Weight: 3.24 kg/m
- Pipe Weight Including Water: 3.7 kg/m
- Reference Standard: ANSI/ASME B36.10
Schedule XS Pipe 1 Inch Table
| NPS | DN | OD (mm) | ID (mm) | Wall Thickness (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 1″ | 25 | 33.4 | 24.3 | 4.55 | 3.24 |
What Does Schedule XS Mean?
Schedule XS stands for Extra Strong. It is a pipe wall designation used in steel pipe standards. The selected schedule affects the wall thickness, which directly affects the inside diameter, pipe weight, fabrication requirements, and support loading.
For a size such as 1 inch DN25 pipe, wall thickness remains important because it affects total pipe weight, handling requirements, support loads, and installation planning in real projects.
Why 1 Inch DN25 Pipe Dimensions Matter
Knowing the exact dimensions of 1 inch Schedule XS pipe is useful for several engineering and construction tasks:
- Fabrication: OD and wall thickness are needed for cutting, beveling, welding, and fit-up work.
- Support Design: Pipe weight per meter helps engineers check support spacing and structural loads.
- Flow Review: ID is useful for estimating internal flow area and hydraulic performance.
- Transport and Lifting: Accurate weight data supports safer handling and planning.
- Schedule Comparison: Engineers often compare XS with STD, Sch 40, Sch 60, or Sch 80 during design review.
Typical Applications of 1 Inch Schedule XS Pipe
This pipe size may be used in:
- Industrial process piping
- Water transmission systems
- Power and utility projects
- Plant piping works
- Infrastructure construction
- Custom steel fabrication and spool projects
Engineering Notes
NPS means Nominal Pipe Size, while DN means Diameter Nominal. Although this pipe is called 1 inch, the actual outside diameter is 33.4 mm according to the standard. The inside diameter changes with the pipe schedule because wall thickness changes from one schedule to another.
That means if you compare the same 1 inch pipe in a different schedule, the OD usually stays the same, while the ID, wall thickness, and pipe weight will change.
Reference
The dimension data on this page is based on ANSI/ASME B36.10, which is widely used for steel pipe dimensions in industrial applications.
How to Use This Pipe Reference
Start with the outside diameter when checking clearances, clamps, sleeves, branch connections, and fabrication fit-up. Use the wall thickness to distinguish this extra-strong section from other schedule choices. The resulting inside diameter is the more useful dimension for reviewing internal flow space and connection alignment.
The listed pipe weight is useful for material takeoffs, handling plans, support-load checks, and transportation estimates. The water-filled weight provides a separate planning reference for systems where the pipe contents contribute to the supported load. Actual project loads may also include insulation, lining, valves, fittings, fluid density, and temporary equipment.
Drafting and Fabrication Considerations
When preparing a spool, layout, or model, do not treat the nominal size as the measured outside diameter. Coordinate the pipe OD with fittings, flanges, supports, penetrations, and adjacent equipment. The DWG download can help with CAD coordination, but the drawing should still be checked against the applicable project specification and fabrication requirements before release.
For a broader piping workflow, compare this reference with related resources on pipe schedules, steel pipe dimensions, pipe fittings, flange dimensions, and pipe support design. These topics help connect the straight-pipe dimensions to the components and checks used in a complete piping layout.
Important Verification Notes
- Confirm whether the project requires seamless or welded pipe and verify the applicable material specification.
- Check that the selected fittings and flanges match the pipe size, outside diameter, wall condition, and connection standard.
- Use the weight data as a planning input, then include contents and attached components when checking supports or lifting arrangements.
- Verify dimensions at the procurement and fabrication stages because project specifications and manufacturer documentation govern the supplied product.
Frequently Asked Questions
What does XS mean for 1 inch pipe?
XS means Extra Strong. It identifies a heavier wall designation than lighter pipe options for the same nominal pipe size. The thicker wall affects the inside diameter and pipe weight.
Is 1 inch pipe the same as a 33.4 mm outside diameter?
Not exactly. 1 inch is the nominal pipe size, while 33.4 mm is the listed outside diameter for this pipe size. Nominal size should not be treated as a direct measurement of the pipe OD.
Why is the inside diameter important?
The inside diameter defines the available internal passage. It is therefore relevant to flow review, connection alignment, internal clearances, and comparison with another schedule of the same nominal size.
What is the listed weight of 1 inch Schedule XS pipe?
The page lists the pipe weight as 3.24 kg/m and also provides a separate pipe-weight figure including water. Use the appropriate value for the task and account for fittings, valves, insulation, and other attached items where applicable.
Can the DWG file be used directly for fabrication?
The DWG is a CAD reference for coordination and drafting. Before fabrication, verify its geometry and project-specific requirements against the authoritative dimension data, purchase specification, and approved drawings.