Size & Dimension
Pipe Dimensions are covered in following Standards
ASME B36.10 – Welded and Seamless Wrought Steel Pipe (Carbon & Alloy Steel)
ASME B36.19 – Stainless Steel Pipe
Three different terms are commonly used to define the size of the pipe.
1. NPS – Nominal Pipe Size All American standard used NPS designation to define pipe size. This is a modern derivation of earlier IPS – Iron Pipe Size. NPS is not an OD or ID of the pipe it is in-between of the outer and the inner diameter of the pipe. For example, NPS 2 size pipe outside diameter is 60 mm or 2.375 inches. In general, NPS 12 and the smaller pipe has outside diameter greater than the size and for NPS 14 and above size pipe outside diameter is the same as the size in inches.
2. NB – Nominal Bore This is the European equivalent of NPS. In this standard pipe sizes are mentioned in millimeter
3. DN – Diameter nominal
In the below table, you can see the correlation of pipe size and OD.
Pipe Dimensions are covered in following Standards
ASME B36.10 – Welded and Seamless Wrought Steel Pipe (Carbon & Alloy Steel)
ASME B36.19 – Stainless Steel Pipe
Three different terms are commonly used to define the size of the pipe.
1. NPS – Nominal Pipe Size All American standard used NPS designation to define pipe size. This is a modern derivation of earlier IPS – Iron Pipe Size. NPS is not an OD or ID of the pipe it is in-between of the outer and the inner diameter of the pipe. For example, NPS 2 size pipe outside diameter is 60 mm or 2.375 inches. In general, NPS 12 and the smaller pipe has outside diameter greater than the size and for NPS 14 and above size pipe outside diameter is the same as the size in inches.
2. NB – Nominal Bore This is the European equivalent of NPS. In this standard pipe sizes are mentioned in millimeter
3. DN – Diameter nominal
In the below table, you can see the correlation of pipe size and OD.
| NPS | 1 | 1 ½ | 2 | 3 | 4 | 6 | 8 |
| NB / DN | 25 | 40 | 50 | 80 | 100 | 150 | 200 |
| OD in mm | 33.4 | 48.3 | 60.3 | 88.9 | 114 | 168 | 219 |
Material
ASME B31.3 provides the list of material that can be used in Process Piping. in below table, you can see the most commonly used material types & their Grades.
Applications
Duplex stainless steels are typically used in:
Heat Resistance
The high chromium content of duplex stainless steels that protects against corrosion, causes embrittlement at temperatures over about 300°C.
At low temperatures duplex stainless steels have better ductility than the ferritic and martensitic grades. Duplex grades can readily be used down to at least -50°C.
Copper Nickel tubes, CUNI
Application range: Copper-Nickel Alloy tube for condenser and heat-exchangers, Water Evaporators, Boiler Blowdown Heat Exchangers, air coolers, Gland Steam Condensers, Steam Ejector, Turbine Oil Coolers, Fuel Oil Heaters, Compressed Air Inter and After Coolers, Ferrules, Oil Well Pump Liner, and Distiller etc.
Copper Nickel tubes, CUNI 70/30 – C71500 – has, in general, the best resistance of any of the copper alloys to impingement attack and to corrosion from most acids and waters. It is being used in severe corrosive conditions in which service lives longer than those of other copper alloys are desired.
ASME B31.3 provides the list of material that can be used in Process Piping. in below table, you can see the most commonly used material types & their Grades.
| Carbon steel Used up to 425°c | Stainless steel Used for corrosive fluid | Low alloy steel Used for temp > (425°c) | Low temp carbon steel Used for temp < (-29°c) |
|
A53 Gr B A106 Gr B API 5L Gr B |
A312 Gr TP304 A312 Gr TP316 A312 Gr TP321 |
A335 Gr P2 , P12, P11, P22, P5, P9 | A333 Gr 6 |
Applications
Duplex stainless steels are typically used in:
- Chemical processing, transport and storage
- Oil and gas exploration and offshore rigs
- Oil and gas refining
- Marine environments
- Pollution control equipment
- Pulp & paper manufacturing
- Chemical process plant
Heat Resistance
The high chromium content of duplex stainless steels that protects against corrosion, causes embrittlement at temperatures over about 300°C.
At low temperatures duplex stainless steels have better ductility than the ferritic and martensitic grades. Duplex grades can readily be used down to at least -50°C.
Copper Nickel tubes, CUNI
Application range: Copper-Nickel Alloy tube for condenser and heat-exchangers, Water Evaporators, Boiler Blowdown Heat Exchangers, air coolers, Gland Steam Condensers, Steam Ejector, Turbine Oil Coolers, Fuel Oil Heaters, Compressed Air Inter and After Coolers, Ferrules, Oil Well Pump Liner, and Distiller etc.
Copper Nickel tubes, CUNI 70/30 – C71500 – has, in general, the best resistance of any of the copper alloys to impingement attack and to corrosion from most acids and waters. It is being used in severe corrosive conditions in which service lives longer than those of other copper alloys are desired.
