This reference provides the dimensional and weight data for Schedule STD Pipe 1 Inch (DN25), including the nominal size designation, outside and inside diameters, wall thickness, and listed pipe weight. Use the page when checking piping layouts, preparing material take-offs, coordinating fittings and flanges, or reviewing a CAD drawing.
For broader project work, compare this entry with the site’s related references for pipe schedules, NPS and DN designations, pipe fittings, flanges, and pipe support loads. These related topics help connect dimensional reference data with drafting, procurement, and installation decisions.
Schedule STD Pipe 1 Inch (DN25) is a steel pipe size commonly used in industrial and utility piping systems where standard dimensions, structural reliability, and dependable flow capacity are important. Based on the current page data under ANSI/ASME B36.10, this pipe size has an outside diameter of 33.4 mm, an inside diameter of 26.64 mm, a wall thickness of 3.38 mm, and a pipe weight of 2.5 kg/m.
1 Inch Schedule STD Pipe Dimensions
The following values are listed for NPS 1 Schedule STD pipe, which corresponds to DN25 in metric designation.
- Pipe Size: NPS 1 Inch
- DN Size: DN25
- Outside Diameter (OD): 33.4 mm
- Inside Diameter (ID): 26.64 mm
- Wall Thickness: 3.38 mm
- Pipe Weight: 2.5 kg/m
- Pipe Weight Including Water: 3.05 kg/m
- Reference Standard: ANSI/ASME B36.10
Schedule STD Pipe 1 Inch (DN25) Data Table
| Pipe Schedule | NPS | DN | OD (mm) | ID (mm) | Wall Thickness (mm) | Weight (kg/m) |
|---|---|---|---|---|---|---|
| STD | 1 Inch | 25 | 33.4 | 26.64 | 3.38 | 2.5 |
What Is Schedule STD Pipe?
Schedule STD means Standard Weight in the IPS pipe system and is commonly referenced for carbon steel and steel pipe dimensions under ASME B36.10. In practical piping work, Schedule STD is used as a standard wall thickness designation for many nominal pipe sizes. It helps engineers, fabricators, and buyers confirm dimensional compatibility, estimate weight, and coordinate with fittings, flanges, supports, and structural loads.
Common Uses of 1 Inch Schedule STD Pipe
1 inch Schedule STD pipe is commonly used in industrial and utility piping systems where good flow capacity and standard steel pipe dimensions are required. This size is often selected for water, cooling, transmission, and plant services where reliable dimensional data is important for design, fabrication, and construction.
- Water transmission lines for plant and utility service
- Cooling water systems in industrial facilities
- Stormwater and drainage piping in infrastructure projects
- Industrial utility piping for bulk fluid transport
- Pipeline headers and manifolds in process plants
- Pump suction and discharge lines where standard pipe dimensions are needed
- Municipal and public works projects requiring steel pipe sizes
- Replacement and upgrade projects where standard pipe dimensions are required
In practical engineering work, this pipe size may be reviewed when checking flow capacity, support loading, transport weight, handling requirements, and installation planning. Final pipe selection should always be verified against project pressure, temperature, fluid type, corrosion allowance, and material specifications.
Why OD, ID, Thickness, and Weight Matter
Exact OD, ID, wall thickness, and weight values are important for support design, material take-off, transport planning, lifting studies, welding preparation, and installation work. For a pipe size such as 1 inch DN25, accurate weight data is useful for support design, material planning, and installation review. Inside diameter is also important for flow calculations and hydraulic capacity review.
NPS 1 and DN25 Explained
NPS means nominal pipe size in inch units, while DN means diameter nominal in metric units. The current page identifies this pipe as NPS 1 and DN25, which is the standard naming format widely used in piping drawings, specifications, and procurement documents.
Conclusion
Schedule STD Pipe 1 Inch (DN25) is listed on the current page with 33.4 mm OD, 26.64 mm ID, 3.38 mm wall thickness, and 2.5 kg/m weight. It is a useful steel pipe reference for engineers, designers, and buyers who need standard dimensional and weight data for piping systems and project coordination.
How to Use This Pipe Reference
The dimensional list and data table should be read together. The nominal designation identifies the pipe size used in drawings and specifications, while the outside diameter is important when coordinating clamps, supports, sleeves, fittings, and connection details. The inside diameter is the primary dimensional reference for flow-area and hydraulic review.
Wall thickness helps distinguish the listed standard-weight configuration from other pipe schedule options. It also matters during fabrication, welding preparation, corrosion-allowance review, and dimensional checks at connections. The listed weight supports material take-offs, handling plans, support reactions, and transport estimates, but project calculations should account for the actual pipe, contents, insulation, valves, fittings, and other attached items where applicable.
Coordination With Drawings and Components
When this size is used in a piping model or layout, coordinate the pipe dimensions with the selected elbows, tees, reducers, flanges, valves, supports, and connection standards. Nominal size labels are not a substitute for checking the mating component dimensions and project specification.
The downloadable DWG reference can support drafting and layout workflows. Before issuing a drawing for fabrication or construction, confirm units, layer conventions, connection details, material requirements, and the governing project documents. A CAD representation is a drafting aid; it does not replace dimensional verification or engineering review.
Design Review Considerations
- Confirm that the listed pipe configuration matches the project piping class and material specification.
- Check pressure, temperature, fluid, corrosion, joining, and inspection requirements independently.
- Use the listed dimensions when coordinating clearances, supports, openings, and connected components.
- Review whether operating contents and attached components affect support or lifting calculations.
- Link this reference with the site’s pages on pipe schedules, flange dimensions, fitting dimensions, and piping terminology for a complete coordination workflow.
Frequently Asked Questions
What does Schedule STD mean for this pipe?
Schedule STD means Standard Weight in the referenced steel pipe dimensional system. It identifies a standard dimensional configuration for the nominal pipe size; it is not, by itself, a complete pressure-design qualification.
Are NPS 1 and DN25 the same designation?
This page identifies the pipe as NPS 1 and DN25. NPS is the nominal pipe size convention expressed in inches, while DN is the metric nominal designation used in drawings, specifications, and procurement documents.
Why are both OD and ID provided?
Outside diameter is useful for physical coordination, supports, sleeves, and fittings. Inside diameter is used for flow-area review and hydraulic calculations. Both dimensions should be checked against the project’s selected components and specifications.
Can the listed pipe weight be used for support design?
The listed pipe weight is useful for preliminary material planning and load review. Final support design should also consider contents, insulation, valves, fittings, operating conditions, span, restraint, and the applicable engineering requirements.
Does Schedule STD alone specify the pipe material?
No. The schedule describes dimensional characteristics. Material grade, manufacturing requirements, testing, coating, corrosion allowance, and service limits must come from the project specification and applicable material requirements.
What is the DWG file used for?
The DWG file is intended as a drafting and layout reference. Verify its units and geometry against the authoritative dimensional data before using it for fabrication, procurement, or construction documentation.