Order for the wrong pipe size is among the commonest and costliest mistakes in the industrial sector. A pipe that is too thin can burst under pressure, and a mismatching diameter and fittings can bring work to a standstill. There is little room for these mistakes on Saudi oil and gas, petrochemical and infrastructure projects. With a reliable seamless pipe size chart in hand, engineers and buyers can double-check the outside diameter, wall thickness and schedule before any order goes out. This will guide you not only on how to read one but which sizes would be preferred for a few common Saudi applications. Visit our page if you want to buy seamless pipe.
Standard Seamless Pipe Sizes and Dimensions
Every seamless pipe size chart is built on three values:
- NPS (Nominal Pipe Size): The trade name of the pipe, such as 2″ or 6″
- OD (Outside Diameter): The actual outer measurement, which stays fixed for each NPS
- WT (Wall Thickness): The thickness of the pipe wall, set by the schedule
Each size keeps a fixed OD, but the wall gets thicker as the schedule goes up. A thicker wall reduces the inside diameter and raises the pressure rating.
Seamless Pipe Size Chart in mm
| NPS (Inches) | Outside Diameter / OD (mm) | Schedule 40 Wall Thickness / WT (mm) | Schedule 80 Wall Thickness / WT (mm) |
| 1/2″ | 21.3 | 2.77 | 3.73 |
| 1″ | 33.4 | 3.38 | 4.55 |
| 2″ | 60.3 | 3.91 | 5.54 |
| 3″ | 88.9 | 5.49 | 7.62 |
| 4″ | 114.3 | 6.02 | 8.56 |
| 6″ | 168.3 | 7.11 | 10.97 |
| 8″ | 219.1 | 8.18 | 12.70 |
| 10″ | 273.1 | 9.27 | 15.09 |
| 12″ | 323.9 | 10.31 | 17.48 |
Based on ASME B36.10M. Always confirm final dimensions with your project specification.
To estimate the weight of carbon steel pipe, use this formula: Weight (kg/m) = (OD − WT) × WT × 0.02466. For example, a 4″ Sch 40 pipe weighs about 16.1 kg/m.
Seamless Pipe Schedule Chart: SCH 10, SCH 40, SCH 80 and More
A pipe’s schedule indicates its wall thickness. Higher schedules handle higher pressure but add weight.
| NPS (Inches) | Schedule 10S (mm) | Schedule 40 (mm) | Schedule 80 (mm) | Schedule 160 (mm) |
| 1″ | 2.77 | 3.38 | 4.55 | 6.35 |
| 2″ | 2.77 | 3.91 | 5.54 | 8.74 |
| 4″ | 3.05 | 6.02 | 8.56 | 13.49 |
| 6″ | 3.40 | 7.11 | 10.97 | 18.26 |
| 8″ | 3.76 | 8.18 | 12.70 | 23.01 |
- SCH 10 / 10S: Thin wall for low-pressure lines, mainly in stainless steel
- SCH 40: The most common choice for general industrial service
- SCH 80: A heavier wall built for high pressure and physical stress
- SCH 160: Very heavy wall for extreme pressure and critical process lines
SS 316 Seamless Pipe Size Chart
Stainless steel pipe follows ASME B36.19M and uses “S” schedules, such as 10S, 40S and 80S. An SS 316 seamless pipe size chart matches carbon steel Sch 40 and 80 up to 10″. From 12″ upward, the stainless walls are thinner. For example, a 12″ Sch 40S pipe has a 9.53 mm wall, while a 12″ Sch 40 pipe has 10.31 mm.
Seamless Pipe Sizes for Oil and Gas, Construction, and Industrial Applications
Oil and gas: A seamless pipe size chart for oil and gas usually adheres to API 5L or ASTM A106. Sch 80 or Sch 160 is used for process and high pressure lines as well with sour service lines requiring thicker walls as corrosion allowance.
Construction: Most Sch 40 pipes are used in building services/other structures at range 1″-6″ for fire fighting and HVAC systems.
Industrial plants: Industries like desalination, chemicals and food often use SS 316 in Sch 10S and 40S Approximate as it is corrosion resistant material for those areas (aramco site) such as Jeddah, Jubail And Dammam.
Factors to Consider When Selecting Seamless Pipes in Saudi Arabia
Pressure and temperature: Adjust the schedule to fit your design conditions
Corrosion: Salty ocean air and/or saline water necessitate stainless steel or thicker wall
Standards: Verify ASTM, API or ASME specifications prior to ordering
Fittings and flanges: Ensure that the schedule is consistent among all parts attached
Mill test certificates: Always check that the paperwork must match with the grade, size and wall thickness
Choosing the Best Place to Buy Seamless Pipes in Saudi Arabia: Shamry Trading
Even the best size chart is good for nothing if your supplier consistently fails to deliver what that chart promises. Shamry Trading has been supplying seamless carbon steel and SS 316 pipes, pipe fitting and valves for oil & gas projects, construction and industrial projects all over Saudi Arabia. Prior to ordering, we verify every size / schedule / specification with you, so the pipes fit perfectly from the start.
Contact us today, tell us about your project requirements and will help you find the right seamless pipe for your project with Shamry Trading.
Conclusion
A seamless pipe size chart lets you pair the right OD, wall thickness and schedule with your pressure and temperature needs. Carbon steel follows ASME B36. Both SS 316 and SS 316L are manufactured from A240M, which is an ASME B36 material. 19M with “S” schedules. When it comes to oil and gas service, wall thicknesses and corrosion allowance generally are the key parameters.
Get the right size today, and sleep easy with a pipeline built for years of performance.
FAQs:
How do you read a seamless pipe size chart?
Find the NPS, check the OD, then pick the schedule for the wall thickness you need.
Which schedule is best for oil and gas lines in Saudi Arabia?
Sch 80 or Sch 160 for high-pressure lines, with extra thickness for sour service.
Is the SS 316 seamless pipe size chart the same as carbon steel?
Up to 10″, yes. From 12″ upward, the stainless walls are thinner.
Why is the seamless pipe size chart in mm important for Saudi buyers?
Most Saudi drawings and site teams use mm, so it prevents ordering mistakes.
Does a higher schedule mean a stronger pipe?
Yes. A thicker wall handles more pressure, but it also adds weight.
