This reference brings together the key dimensional and identification information for Schedule 5S Pipe 18 Inch (DN450). Use it to review the pipe’s outside diameter, inside diameter, wall thickness, listed weight, and water-filled weight before coordinating layouts, supports, procurement, or fabrication documents.
The page also explains how NPS, DN, pipe schedule, and stainless steel pipe standards relate to one another. For drawing and drafting work, the linked DWG resource can support preliminary coordination, but project documents should still be checked against the applicable specification and approved dimensional data.
Schedule 5S Pipe 18 Inch (DN450 mm) is a stainless steel pipe size commonly used in large piping systems where corrosion resistance and lighter wall thickness are important. This pipe size is typically referenced under ANSI/ASME B36.19, the standard used for stainless steel pipe dimensions.
For this size, the pipe has an outside diameter (OD) of 457 mm, an inside diameter (ID) of 448.62 mm, and a wall thickness of 4.19 mm. The listed pipe weight is 46.79 kg/m, while the weight including water is 204.77 kg/m.
Schedule 5S Pipe 18 Inch (DN450 mm) Dimension Table
| Pipe Size | NPS | DN | Outside Diameter (OD) | Inside Diameter (ID) | Wall Thickness | Weight |
|---|---|---|---|---|---|---|
| Schedule 5S Pipe | 18 Inch | DN450 | 457 mm | 448.62 mm | 4.19 mm | 46.79 kg/m |
What Is Schedule 5S Pipe?
Schedule 5S is a thin-wall stainless steel pipe schedule listed in ASME B36.19. The “S” designation is generally used for stainless steel pipe schedules. Compared with heavier pipe schedules, Schedule 5S provides a lower wall thickness and lighter pipe weight, which can help reduce fabrication load, support requirements, and handling effort in suitable applications.
However, pipe schedule selection should always be checked against design pressure, temperature, corrosion allowance, code requirements, and service conditions before use.
18 Inch Schedule 5S Pipe Data
- Standard: ANSI/ASME B36.19
- Pipe Type: Stainless Steel Pipe
- NPS: 18 Inch
- DN: DN450
- OD: 457 mm
- ID: 448.62 mm
- Wall Thickness: 4.19 mm
- Pipe Weight: 46.79 kg/m
- Weight Including Water: 204.77 kg/m
Common Uses of 18 Inch Schedule 5S Pipe
18 inch Schedule 5S stainless steel pipe may be used in systems where a large internal flow area and corrosion-resistant material are needed. Typical applications may include:
- Water treatment and utility piping systems
- Industrial stainless steel process lines
- Low-pressure transfer piping
- Food and beverage production systems
- Chemical and general fabrication projects
Why DN450 Pipe Dimensions Matter
Many users search for DN450 pipe dimensions to verify piping layout, support design, transport limits, fabrication requirements, and compatibility with fittings or connected equipment. For large-diameter pipe, accurate dimensions are important for spool coordination, structural loading checks, and installation planning.
Knowing the correct 18 inch Schedule 5S pipe dimensions also helps engineers, designers, estimators, buyers, and students compare this pipe size with other schedules when reviewing wall thickness, internal flow area, and total pipe weight.
NPS 18 and DN450 Explained
NPS stands for Nominal Pipe Size in inches, while DN stands for Diameter Nominal in metric designation. For this pipe size:
- NPS 18 = inch-based nominal pipe size
- DN450 = metric nominal designation
Although DN is shown in metric form, the actual outside diameter should always be checked from the dimensional standard. For this size, the OD is 457 mm.
Reference for Schedule 5S Pipe 18 Inch
This page provides a quick dimensional reference for engineers, piping designers, students, fabricators, and procurement teams looking for Schedule 5S Pipe 18 Inch (DN450 mm) data in a clear format.
Reference Standard: ANSI/ASME B36.19 stainless steel pipe dimensions.
How to Read This Schedule 5S Pipe Reference
The table separates the pipe’s nominal identification from its measured dimensional properties. NPS 18 and DN450 identify the nominal size, while OD, ID, and wall thickness describe the physical geometry used for layout and coordination.
For piping designers, the outside diameter is especially important when coordinating clamps, supports, sleeves, clearances, and connections. The inside diameter is useful when reviewing available flow passage and matching the pipe to process or hydraulic requirements. Wall thickness helps distinguish this schedule from other stainless steel pipe options, but it should not be treated as a pressure-design decision by itself.
Using the Weight Information
The listed pipe weight supports preliminary material takeoffs, handling reviews, transport planning, and support-load coordination. The water-included value is useful when considering the additional operating load associated with a filled line. Final support and structural checks should also account for the complete project configuration, including fittings, valves, insulation, contents, restraints, and applicable load cases.
Schedule, Material, and Design Verification
The “5S” designation identifies a stainless steel pipe schedule with a relatively light wall compared with heavier schedules. Schedule selection must be verified against the governing design code, pressure and temperature conditions, corrosion requirements, fabrication rules, and service-specific specifications. Dimensional compatibility does not by itself confirm that a pipe is acceptable for a particular service.
Related Pipe Reference Topics
Readers comparing this entry with other pipe products may also benefit from related references on pipe schedules, NPS and DN designations, stainless steel pipe dimensions, pipe fittings and flanges, and piping CAD and DWG resources. These topics help connect dimensional data with drafting, component selection, and installation planning.
Frequently Asked Questions
What does Schedule 5S mean?
Schedule 5S is a stainless steel pipe schedule designation associated with the dimensional reference identified on this page. It describes a lighter-wall pipe option than heavier schedules, but the schedule alone does not establish whether the pipe meets a project’s pressure, temperature, corrosion, or code requirements.
Are NPS 18 and DN450 the same designation?
They are the inch-based and metric nominal designations used to identify this pipe size. Nominal designations are not a substitute for checking the actual dimensional properties listed in the applicable reference.
Why are both OD and ID shown?
OD is commonly used for external coordination, including supports, sleeves, and clearances. ID helps describe the available internal passage and can be relevant to flow and equipment coordination. The wall thickness connects the external and internal dimensions.
What is the purpose of the weight including water?
It provides a reference for the line condition when the pipe contains water. This can support preliminary load discussions, but final engineering checks should include all relevant contents, components, insulation, restraints, and load combinations.
Can the DWG file be used for final fabrication?
The DWG is a drafting and coordination resource. Before fabrication or construction, verify the drawing against the approved project specification, applicable standard, connection details, tolerances, and controlled engineering documents.
Does Schedule 5S automatically define allowable pressure?
No. Allowable pressure depends on factors such as material specification, design temperature, manufacturing requirements, corrosion considerations, code rules, and project-specific design conditions. A qualified engineer should verify suitability for the intended service.