This reference page brings together the dimensional and weight information needed to review 3/4 inch Schedule 80S stainless steel pipe, also identified as DN20. Use the data when checking piping layouts, material take-offs, fabrication details, support loads, and procurement documents.
The table is most useful when read alongside related references for pipe dimensions and schedules, stainless steel pipe, pipe fittings and flanges, and piping terminology. The downloadable DWG can also support drafting and coordination workflows, subject to project-specific drawing review.
Schedule 80S Pipe 3/4 Inch (DN20) is a stainless steel pipe size commonly used in industrial piping systems where corrosion resistance, dimensional consistency, and dependable wall thickness are important. Based on the current page data under ANSI/ASME B36.19, this pipe size has an outside diameter of 26.7 mm, an inside diameter of 18.88 mm, a wall thickness of 3.91 mm, and a pipe weight of 2.2 kg/m.
3/4 Inch Schedule 80S Pipe Dimensions
The following values are listed for NPS 3/4 Schedule 80S pipe, which corresponds to DN20 in metric designation.
- Pipe Size: NPS 3/4 Inch
- DN Size: DN20
- Outside Diameter (OD): 26.7 mm
- Inside Diameter (ID): 18.88 mm
- Wall Thickness: 3.91 mm
- Pipe Weight: 2.2 kg/m
- Pipe Weight Including Water: 2.47 kg/m
- Reference Standard: ANSI/ASME B36.19
Schedule 80S Pipe 3/4 Inch (DN20) Data Table
| Pipe Schedule | NPS | DN | OD (mm) | ID (mm) | Wall Thickness (mm) | Weight (kg/m) |
|---|---|---|---|---|---|---|
| 80S | 3/4 Inch | 20 | 26.7 | 18.88 | 3.91 | 2.2 |
What Is Schedule 80S Pipe?
Schedule 80S is a stainless steel pipe schedule designation commonly used under ASME B36.19. In piping design and fabrication, the schedule identifies the wall thickness series for a given nominal pipe size. This helps engineers, buyers, and fabricators confirm dimensional compatibility, estimate pipe weight, and coordinate with fittings, flanges, and supports.
Common Uses of 3/4 Inch Schedule 80S Pipe
3/4 inch Schedule 80S pipe is commonly used in stainless steel piping systems that require good corrosion resistance, dependable wall thickness, and reliable flow capacity. This size is often selected for industrial projects where standard dimensions are needed for design, fabrication, procurement, and installation work.
- Process piping systems in chemical and industrial plants
- Utility and service piping for water, air, and general process lines
- Cooling water and auxiliary piping in plant facilities
- Marine and offshore piping where stainless steel is preferred
- Food and beverage plants requiring corrosion-resistant piping materials
- Pharmaceutical facilities using stainless steel process lines
- Instrument and small-bore piping systems in industrial service
- Pipeline modification and replacement work where standard pipe dimensions are required
In practical engineering work, this pipe size may be checked when reviewing flow area, piping layout, support loading, transport weight, and installation requirements. Final pipe selection should always be verified against project pressure, temperature, fluid type, and material specifications.
Why OD, ID, Thickness, and Weight Matter
Exact OD, ID, wall thickness, and weight values are important for pipe support design, material take-off, transport planning, welding preparation, and installation work. Weight data is also useful for lifting calculations and total piping load estimates, while inside diameter affects flow calculations and system capacity review.
NPS 3/4 and DN20 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 3/4 and DN20, which is the standard naming format widely used in piping drawings, isometrics, and procurement specifications.
Conclusion
Schedule 80S Pipe 3/4 Inch (DN20) is listed on the current page with 26.7 mm OD, 18.88 mm ID, 3.91 mm wall thickness, and 2.2 kg/m weight. It is a useful stainless steel pipe reference for piping engineers, designers, and buyers who need standard dimensional and weight data for project planning and material selection.
How to Use This Pipe Reference
Start with the nominal designations, then compare the listed outside diameter, inside diameter, wall thickness, and weight with the requirements of the piping system. These values serve different purposes: outside diameter supports layout and connection coordination, inside diameter supports flow-area review, wall thickness supports fabrication and engineering checks, and weight supports material planning and load estimates.
Schedule and material checks
The 80S designation identifies a stainless steel wall-thickness series associated with the referenced dimensional standard. It should not be treated as a complete pressure-design specification by itself. Final selection also requires review of the project material specification, fluid service, operating conditions, joining method, corrosion requirements, and applicable design rules.
Drawing and procurement coordination
When this pipe appears on an isometric, layout, bill of materials, or purchase request, keep the NPS and DN designations together to reduce ambiguity between inch-based and metric-based documentation. Confirm that connected fittings, flanges, valves, and instruments are specified for the same pipe dimensions and material requirements.
The accompanying DWG is useful for drafting reference and coordination. Before incorporating it into a production drawing, verify units, layer conventions, connection details, revision control, and the project specification. For broader design work, this page can be paired with internal references covering pipe schedules, fitting dimensions, flange selection, and CAD/DWG piping resources.
Frequently Asked Questions
What does Schedule 80S mean for this pipe?
Schedule 80S is the stainless steel pipe wall-thickness designation used for the listed reference data. It helps coordinate dimensions, weight, fittings, fabrication, and procurement, but it does not replace the project’s pressure, temperature, material, or corrosion review.
Are 3/4 inch and DN20 the same designation on this page?
Yes. The page identifies this pipe as NPS 3/4 and DN20. NPS is the nominal pipe size designation in inch-based terminology, while DN is the metric nominal designation.
Why are both OD and ID provided?
Outside diameter is important for physical layout and connection coordination, while inside diameter is used when reviewing flow area and system capacity. Comparing both values also helps distinguish the pipe’s dimensional profile from its nominal size name.
What is the pipe weight including water used for?
The listed weight including water provides a reference for reviewing operating or filled-line loads. Support, lifting, and structural checks should still account for the complete project configuration, including fittings, valves, insulation, contents, and support spacing where applicable.
Can the DWG be used directly for fabrication?
The DWG is provided as a drafting reference. Review its units, dimensions, connection requirements, revision status, and project standards before using it for fabrication or issuing it as a construction document.