This reference page is intended for engineers, designers, fabricators, estimators, and CAD users who need to check NPS 8 Schedule 120 pipe dimensions. Use the data below to distinguish nominal size from actual outside and inside diameter, review the effect of a heavy wall on pipe weight, and support early-stage layout or material-estimating work.
For related checks, compare this entry with a pipe schedule chart, review the difference between NPS and DN, and consult related references for pipe fittings, flanges, and pipe support loads. Those subjects help connect dimensional data with the broader piping model.
Schedule 120 pipe 8 inch (DN200) 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 8 Schedule 120 pipe based on ASME B36.10.
8 Inch Schedule 120 Pipe Dimensions
- Nominal Pipe Size (NPS): 8 inch
- Diameter Nominal (DN): DN200
- Outside Diameter (OD): 219.1 mm
- Wall Thickness: 18.26 mm
- Inside Diameter (ID): 182.58 mm
- Pipe Weight: 90.44 kg/m
- Pipe Weight Filled With Water: 116.6 kg/m
- Reference Standard: ASME B36.10
- Pipe Type: Steel Pipe
Schedule 120 Pipe 8 Inch Data Table
| Pipe Size | DN | OD (mm) | Wall Thickness (mm) | ID (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| 8 inch | 200 | 219.1 | 18.26 | 182.58 | 90.44 |
What Does Schedule 120 Mean?
Schedule 120 refers to a 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 8 Inch Schedule 120 Pipe
NPS 8 Schedule 120 pipe is commonly referenced for heavy-duty industrial piping systems where 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 8 inch Schedule 120 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.
8 Inch Schedule 120 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 8 inch Schedule 120 pipe?
The outside diameter is 219.1 mm.
What is the wall thickness of DN200 Schedule 120 pipe?
The wall thickness is 18.26 mm.
What is the inside diameter of NPS 8 Schedule 120 pipe?
The inside diameter is 182.58 mm.
How much does 8 inch Schedule 120 pipe weigh?
The approximate weight is 90.44 kg/m.
Which standard covers this pipe size?
This dimension data is based on ASME B36.10 for steel pipe.
Conclusion
Schedule 120 pipe 8 inch (DN200) has an outside diameter of 219.1 mm, wall thickness of 18.26 mm, inside diameter of 182.58 mm, and a weight of 90.44 kg/m. It is a useful reference for piping design, fabrication, estimating, and heavy-duty industrial engineering work.
How to Use This Pipe Reference
The nominal designation identifies the pipe size family; it is not the same as the measured inside diameter. The outside diameter is the fixed dimensional reference for this pipe size, while the Schedule 120 designation identifies a heavier wall series. Because the wall occupies more of the cross-section, the listed inside diameter is smaller than the outside diameter and the pipe has a greater mass per unit length than lighter-wall alternatives.
Dimension checks for drawings and models
When preparing a piping layout, section view, or CAD model, use the outside diameter for the external envelope and the inside diameter for the flow opening. The wall thickness is useful for section details, connection preparation, and checking whether the selected pipe representation matches the dimensional reference. Do not substitute nominal size for either diameter in a fabrication drawing.
Weight and project coordination
The listed pipe weight supports preliminary material takeoffs, handling reviews, support-load estimates, and transport planning. A complete engineering check may also need to account for fittings, flanges, valves, welds, coatings, insulation, contents, and project-specific design requirements. Confirm the applicable material specification, manufacturing tolerances, and supplier documentation before procurement or final structural verification.
Schedule is not a complete design specification
A schedule identifies a dimensional wall series; it does not, by itself, establish allowable pressure, temperature limits, corrosion allowance, material grade, or code compliance for a particular service. Those decisions require the governing design code, service conditions, material requirements, and qualified engineering review.
Additional Questions About NPS 8 Schedule 120 Pipe
Does the nominal size equal the actual inside diameter?
No. Nominal size is a standardized designation. The actual inside diameter depends on the pipe’s outside diameter and wall thickness, so the dimensional values in the table should be used for layout and calculation work.
Why is the outside diameter important in a CAD drawing?
The outside diameter controls the external envelope of the pipe. It helps coordinate clearances, supports, clamps, insulation space, penetrations, and connections with adjacent equipment or piping.
Can the listed weight be used for a final support design?
It can support preliminary estimating, but final support design should include the complete installed configuration and all applicable permanent and operating loads. Confirm project requirements and supplier data before issuing a final design.
Does Schedule 120 alone determine pressure capacity?
No. Pressure capacity depends on more than wall series, including material, design temperature, corrosion or erosion considerations, joint details, code requirements, and service conditions. A qualified engineer should perform the governing design check.
What should be checked before ordering this pipe?
Verify the nominal size and schedule, material specification, applicable product standard, manufacturing tolerances, length, end condition, inspection requirements, and supplier documentation against the project specification.