Use this reference when you need to check the physical dimensions and handling weight of 14 inch Schedule 140 pipe during piping layout, material takeoff, fabrication planning, or CAD drafting. The page separates nominal pipe identification from the measured outside diameter, wall thickness, and inside diameter so the data can be applied correctly in design documentation.
For project work, compare the listed dimensions with the applicable material specification, purchase documentation, fabrication requirements, and approved engineering data. The table is a dimensional reference; it does not replace project-specific design verification.
Schedule 140 pipe 14 inch (DN350) is a 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 14 Schedule 140 pipe based on ASME B36.10.
14 Inch Schedule 140 Pipe Dimensions
- Nominal Pipe Size (NPS): 14 inch
- Diameter Nominal (DN): DN350
- Outside Diameter (OD): 355.6 mm
- Wall Thickness: 31.75 mm
- Inside Diameter (ID): 292.1 mm
- Pipe Weight: 253.58 kg/m
- Pipe Weight Filled With Water: 320.55 kg/m
- Reference Standard: ASME B36.10
- Pipe Type: Steel Pipe
Schedule 140 Pipe 14 Inch Data Table
| Pipe Size | DN | OD (mm) | Wall Thickness (mm) | ID (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 14 inch | 350 | 355.6 | 31.75 | 292.1 | 253.58 |
What Does Schedule 140 Mean?
Schedule 140 refers to a very 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 thicker wall reduces the inside diameter and significantly increases pipe weight.
Typical Uses of 14 Inch Schedule 140 Pipe
NPS 14 Schedule 140 pipe is commonly referenced for heavy-duty industrial piping systems where very 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 14 inch Schedule 140 pipe, the heavy wall thickness results in much higher installed weight than lighter schedules, so accurate weight data is important for engineering and construction work.
14 Inch Schedule 140 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 14 inch Schedule 140 pipe?
The outside diameter is 355.6 mm.
What is the wall thickness of DN350 Schedule 140 pipe?
The wall thickness is 31.75 mm.
What is the inside diameter of NPS 14 Schedule 140 pipe?
The inside diameter is 292.1 mm.
How much does 14 inch Schedule 140 pipe weigh?
The approximate weight is 253.58 kg/m.
Which standard covers this pipe size?
This dimension data is based on ASME B36.10 for steel pipe.
Conclusion
Schedule 140 pipe 14 inch (DN350) has an outside diameter of 355.6 mm, wall thickness of 31.75 mm, inside diameter of 292.1 mm, and a weight of 253.58 kg/m. It is a useful reference for piping design, fabrication, estimating, and heavy-duty industrial engineering work.
How to Read the 14 Inch Schedule 140 Pipe Data
NPS 14 and DN350 identify the same nominal pipe size in two commonly used designation systems. The nominal designation should not be treated as the actual measured diameter. For layout, connection, and clearance checks, use the listed outside diameter and inside diameter instead.
Outside diameter, wall thickness, and inside diameter
The outside diameter is important for routing, supports, clamps, insulation clearances, and connection details. Wall thickness describes the pipe section between the outside and inside surfaces. The inside diameter is the more relevant dimension for flow-area checks, lining considerations, and internal access, but the appropriate design calculation should use the project requirements and applicable engineering rules.
Schedule is not a complete pressure designation
A schedule identifies a standardized pipe wall-thickness series for a nominal size. It does not, by itself, establish allowable pressure, temperature capability, corrosion life, or suitability for a particular service. Those decisions require review of the material specification, design conditions, joining method, applicable code, manufacturing requirements, and project allowances.
Using the weight data in engineering work
Use the listed pipe weight for preliminary material estimates, shipping studies, lifting plans, support reactions, rack loading, and fabrication planning. Project calculations may also need to account for fluid contents, insulation, coatings, fittings, valves, welds, attachments, and local support conditions. The filled-with-water value is useful for recognizing that operating or test conditions can impose a different load than the bare-pipe condition.
Drafting and procurement checks
- Show the nominal size and schedule consistently in piping specifications, bills of material, and drawing notes.
- Use the outside diameter for physical layout and the inside diameter where internal clearance or flow-related information is required.
- Check that fittings, flanges, valves, and branches are compatible with the selected pipe standard and project specification.
- Confirm material grade, end preparation, length, tolerances, and inspection requirements from the purchase or fabrication documents.
Related PipeSTD references can help extend this check to pipe schedule comparisons, NPS-to-DN terminology, pipe weight calculations, fitting dimensions, flange references, and downloadable CAD/DWG resources.
Additional Questions About 14 Inch Schedule 140 Pipe
Is the nominal size the same as the measured outside diameter?
No. The nominal size is a designation used to identify the pipe size, while the outside diameter is the dimensional value used for physical layout and connection checks.
Can the listed pipe weight be used as the final support load?
It can support preliminary estimates, but final support and structural checks should include all applicable contents, attachments, insulation, fittings, operating conditions, and project load combinations.
Does Schedule 140 identify the pipe material grade?
No. The schedule describes the wall-thickness series. Material grade, mechanical requirements, chemical requirements, and inspection criteria must be confirmed separately in the applicable specification and purchase documents.
Why should the DWG reference be checked against the dimensional table?
A drawing is useful for drafting and spatial coordination, while the dimensional table provides the stated reference values. Checking both helps identify inconsistent assumptions before fabrication or model issue.