Nominal Pipe Size,Outer Diameter,Nominal Bore

　　There are two common methods for designating pipe outside diameter (OD). The North American method is called NPS ("Nominal Pipe Size") and is based on inches (also frequently referred to as NB ("Nominal Bore"). The European version is called DN ("Diametre Nominal" / "Nominal Diameter") and is based on millimetres. Designating the outside diameter allows pipes of the same size to be fit together no matter what the wall thickness.

　　For pipe sizes less than NPS 14 inch (DN 350), both methods give a nominal value for the OD that is rounded off and is not the same as the actual OD. For example, NPS 2 inch and DN 50 are the same pipe, but the actual OD is 2.375 inches or 60.33 millimetres. The only way to obtain the actual OD is to look it up in a reference table.

　　For pipe sizes of NPS 14 inch (DN 350) and greater the NPS size is the actual diameter in inches and the DN size is equal to NPS times 25 (not 25.4) rounded to a convenient multiple of 50. For example, NPS 14 has an OD of 14 inches or 355.60 millimetres, and is equivalent to DN 350.

　　Steel pipe specifications

　　200mm diameter mild steel pipe astm a106

　　0.5 inch Seamless Steel Pipe ASTM A53 SCH40

　　114mm carbon seamless steel pipe china suppliers

　　Hebei shengtian pipe-fitting group Co., ltd is specialized in manufacturing and exporting forged flanges and buttwelded pipe fittings. In additation to the standard products mentioned above, we are also able to make non-standard, special-designed items according to customers’ requirement. Should any of the items be of your interests, please do not hesitate to contact us for latest information.