Use this reference when you need to identify the dimensional and weight data for 18 inch Schedule 160 pipe in piping layouts, fabrication documents, material estimates, or CAD work. The page uses both the NPS designation and the DN450 designation so the same pipe size can be located across U.S. customary and metric-oriented project documentation.
For quick checking, compare the outside diameter, wall thickness, inside diameter, and mass per meter together rather than relying on the nominal size alone. The dimensional table below is the controlling local reference for this entry; related pipe schedules, fittings, flanges, and CAD resources should be checked separately when developing a complete piping package.
Schedule 160 pipe 18 inch (DN450) is an extra heavy-wall steel pipe size commonly used in piping design, fabrication, drafting, and engineering estimation work. This page provides the standard dimensions, wall thickness, inside diameter, and weight per meter for NPS 18 Schedule 160 pipe based on ASME B36.10.
18 Inch Schedule 160 Pipe Dimensions
- Nominal Pipe Size (NPS): 18 inch
- Diameter Nominal (DN): DN450
- Outside Diameter (OD): 457 mm
- Wall Thickness: 45.24 mm
- Inside Diameter (ID): 366.52 mm
- Pipe Weight: 459.39 kg/m
- Pipe Weight Filled With Water: 564.84 kg/m
- Reference Standard: ASME B36.10
- Pipe Type: Steel Pipe
Schedule 160 Pipe 18 Inch Data Table
| Pipe Size | DN | OD (mm) | Wall Thickness (mm) | ID (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 18 inch | 450 | 457 | 45.24 | 366.52 | 459.39 |
What Does Schedule 160 Mean?
Schedule 160 refers to an extra heavy wall thickness series used for steel pipe under ASME B36.10. For the same nominal pipe size, the outside diameter remains fixed while the wall thickness increases according to the schedule. A much thicker wall reduces the inside diameter and significantly increases pipe weight.
Typical Uses of 18 Inch Schedule 160 Pipe
NPS 18 Schedule 160 pipe is commonly referenced for very heavy-duty industrial piping systems where extremely high wall thickness is required. It may be used in process piping, plant utility systems, structural loading checks, fabrication work, and engineering applications where pipe strength and wall thickness are more critical than maximum flow area.
Why Pipe Weight Matters
Pipe weight per meter is essential for transport planning, crane lifting studies, support design, structural loading, fabrication estimates, and installation planning. For an 18 inch Schedule 160 pipe, the extra heavy wall thickness results in much higher installed weight than lighter schedules, so accurate weight data is important for engineering and construction work.
18 Inch Schedule 160 Pipe Calculation Notes
The listed weight is based on standard steel pipe dimensions using the outside diameter and wall thickness of the pipe. Actual product weight may vary slightly depending on manufacturing tolerance, material specification, and supplier standard.
Frequently Asked Questions
What is the outside diameter of 18 inch Schedule 160 pipe?
The outside diameter is 457 mm.
What is the wall thickness of DN450 Schedule 160 pipe?
The wall thickness is 45.24 mm.
What is the inside diameter of NPS 18 Schedule 160 pipe?
The inside diameter is 366.52 mm.
How much does 18 inch Schedule 160 pipe weigh?
The approximate weight is 459.39 kg/m.
Which standard covers this pipe size?
This dimension data is based on ASME B36.10 for steel pipe.
Conclusion
Schedule 160 pipe 18 inch (DN450) has an outside diameter of 457 mm, wall thickness of 45.24 mm, inside diameter of 366.52 mm, and a weight of 459.39 kg/m. It is a useful reference for piping design, fabrication, estimating, and heavy-duty industrial engineering work.
How to Read This 18 Inch Schedule 160 Reference
NPS 18 identifies the nominal pipe size, while DN450 is the corresponding metric designation used in many international and project documents. Neither designation should be treated as the measured outside diameter; the outside diameter and wall thickness listed in the table are the values to use for dimensional coordination.
The schedule describes the wall-thickness series. For this entry, the heavy wall reduces the available inside diameter and produces a substantially higher pipe mass than lighter-wall alternatives at the same nominal size. That relationship is important when reviewing clearances, flow-area assumptions, supports, lifting plans, and material takeoffs.
Practical Checks Before Using the Data
- Use the outside diameter when coordinating pipe routing, clamps, sleeves, supports, and connections.
- Use the inside diameter when checking bore-related clearances or flow-area assumptions.
- Use the listed mass per meter for preliminary handling, support, and structural-load studies, subject to project verification.
- Treat the filled-with-water figure as a reference operating load for the stated contents; actual contents and project conditions may differ.
- Confirm the material specification, manufacturing tolerance, corrosion allowance, joining method, and applicable design code before final engineering decisions.
Related PipeSTD References
This page can be used alongside the site’s pipe schedule dimensions, NPS and DN conversion references, steel pipe weight data, ASME B36.10 terminology, pipe fittings and flange dimensions, and pipe CAD/DWG resources. These related references help connect the straight-pipe dimensions to drafting, procurement, and piping layout work without replacing project specifications or engineering review.
The downloadable DWG is useful as a drafting reference. Before incorporating it into a production drawing, confirm units, layer conventions, connection details, material requirements, and the revision status required by the project.
Additional Questions About 18 Inch Schedule 160 Pipe
Is 18 inch Schedule 160 pipe the same as DN450 pipe?
They are the NPS and DN designations used for the same referenced pipe size in this entry. Always verify the associated outside diameter and wall thickness in the dimensional data rather than matching by label alone.
Why is the inside diameter smaller than the outside diameter?
The inside diameter is obtained after accounting for the pipe wall on both sides of the outside diameter. Because Schedule 160 uses a heavy wall, the difference between the outside and inside dimensions is significant.
Does the listed pipe weight equal the final delivered weight?
No. The listed value is a reference weight per meter based on the stated dimensions. Actual delivered mass can vary with manufacturing tolerances, material requirements, coating, end preparation, and supplier data.
Can the DWG be used directly for fabrication?
Use the DWG as a reference starting point, then check its units, geometry, drawing standards, connection requirements, and project-approved specifications before fabrication.
Does Schedule 160 alone establish a pressure rating?
No. A schedule identifies a dimensional wall-thickness series. Pressure design also depends on material, temperature, code requirements, corrosion or erosion considerations, joint efficiency, manufacturing condition, and other project inputs.