This reference page brings together the key dimensional and weight data for 12 inch Schedule 160 pipe, also identified as NPS 12 and DN300. Use the table for preliminary piping layouts, material takeoffs, fabrication review, support-load checks, and CAD drafting. Because nominal pipe size is a designation rather than a direct measurement, confirm the listed outside diameter, wall thickness, and inside diameter before coordinating connected components.
Schedule 160 identifies a heavy-wall series; it is not, by itself, a complete pressure-rating or design specification. Final selection should also consider the applicable material specification, design temperature, fluid service, corrosion allowance, joining method, and project code requirements.
Schedule 160 pipe 12 inch (DN300) 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 12 Schedule 160 pipe based on ASME B36.10.
12 Inch Schedule 160 Pipe Dimensions
- Nominal Pipe Size (NPS): 12 inch
- Diameter Nominal (DN): DN300
- Outside Diameter (OD): 323.9 mm
- Wall Thickness: 33.32 mm
- Inside Diameter (ID): 257.16 mm
- Pipe Weight: 238.69 kg/m
- Pipe Weight Filled With Water: 290.6 kg/m
- Reference Standard: ASME B36.10
- Pipe Type: Steel Pipe
Schedule 160 Pipe 12 Inch Data Table
| Pipe Size | DN | OD (mm) | Wall Thickness (mm) | ID (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 12 inch | 300 | 323.9 | 33.32 | 257.16 | 238.69 |
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 12 Inch Schedule 160 Pipe
NPS 12 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 a 12 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.
12 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 12 inch Schedule 160 pipe?
The outside diameter is 323.9 mm.
What is the wall thickness of DN300 Schedule 160 pipe?
The wall thickness is 33.32 mm.
What is the inside diameter of NPS 12 Schedule 160 pipe?
The inside diameter is 257.16 mm.
How much does 12 inch Schedule 160 pipe weigh?
The approximate weight is 238.69 kg/m.
Which standard covers this pipe size?
This dimension data is based on ASME B36.10 for steel pipe.
Conclusion
Schedule 160 pipe 12 inch (DN300) has an outside diameter of 323.9 mm, wall thickness of 33.32 mm, inside diameter of 257.16 mm, and a weight of 238.69 kg/m. It is a useful reference for piping design, fabrication, estimating, and heavy-duty industrial engineering work.
How to Use This Schedule 160 Pipe Reference
For layout work, the outside diameter is the primary dimension for coordinating pipe clearances, clamps, guides, sleeves, and other external interfaces. The inside diameter is more relevant to flow-area checks, internal access, and lining or coating considerations. The wall thickness describes the difference between these two diameter references and helps distinguish this heavy-wall series from lighter schedules in the same nominal size.
The listed pipe weight is useful for estimating linear material mass and for developing preliminary support, lifting, transport, and structural load cases. The water-filled figure represents a different loading condition from the empty-pipe value. In an engineering model, consider the applicable operating, test, insulation, valve, fitting, and support loads rather than treating one table value as the complete installed load.
Related Piping and Drafting References
When using this page for a piping package, it can be helpful to review related references covering pipe schedules, NPS and DN terminology, pipe flange dimensions, fitting dimensions, and pipe support design. A CAD or DWG reference for this size can also help with preliminary drawing coordination, but the drawing should be checked against the project specification and the selected manufacturer or supplier data before fabrication.
For purchasing or design release, compare the dimensional record with the applicable material documentation and inspection requirements. Manufacturing tolerances, product condition, and supplier practices can affect the delivered item even when the nominal schedule designation is the same.
Schedule 160 Pipe Reference Questions
Does Schedule 160 alone establish the allowable working pressure?
No. Schedule designates a wall-thickness series for a nominal pipe size. Allowable pressure depends on additional factors such as material, temperature, design code, corrosion allowance, manufacturing requirements, and the service conditions.
Why should the outside diameter be checked when the nominal size is known?
Nominal size is a standardized designation and should not be used as the measured outside diameter. The listed outside diameter is the dimension to use for external fit-up, clearances, supports, and connected components.
When should the water-filled weight be used?
Use it as a reference for a water-filled loading condition. Actual support and structural checks may also need to include insulation, fittings, valves, test media, contents with a different density, and other attached equipment.
Can this page replace project or supplier documentation?
No. This page is a dimensional and estimating reference. Confirm procurement, fabrication, pressure design, and inspection details against the governing project documents and approved supplier information.