The marking method of stainless steel pipe OD,Diameter and WT
Stainless steel pipe welding flange diameter usually used nominal size or nominal diameter, metric unit marked with DN, followed by the value of millimeters, in order to facilitate the adoption of rounded values, pipe diameter Created a common logo.
It should be noted that, between different standards or uniform standards, of course, the nominal size is similar to the butt elbow but the approximate diameter size is different. In addition to the nominal size, it is also useful that the outside diameter or inside diameter of the pipe emerge directly in millimeters. In the manipulation of some foreign standards, the stamping elbow will encounter the nominal size of the products appear in English units, the difference between the price of large.
The simplest and easiest way to express it is: The actual outer diameter of the pipe * The actual wall thickness, for example: Φ114.3 * 6.02 means the outer diameter of the pipe is 114.3mm and the wall thickness is 6.02mm. However, in many cases, for the convenience of design, the diameter of the pipe is usually indicated by the nominal diameter, for example, DN100, 4 ", etc. The wall thickness is indicated by the symbol SCH ××, as indicated by SCH 80. These values do not represent the actual outer diameter or actual Wall thickness, they are just a logo.Because of the habits of the countries in the world, some nominal diameter (such as DN100) represented by the actual diameter is not the only, summed up, there are mainly two, one called the metric series (Series B) and a type called Imperial Series (Series A), so if we only know the nominal diameter and do not know whether it belongs to the A series or the B series, we can not uniquely determine its actual outer diameter. For example, DN100, A series, the representative of the tube diameter is 114.3mm, if the B series, a representative of the outer diameter of 108mm.But DN100A on behalf of the outer diameter of 114.3, DN100B on behalf of the outer diameter of 108. High pressure flange
As for the thickness of the pipe usually given in accordance with the label (such as SCH20, STD, XS), check the relevant standards in the table, you can find the actual wall thickness on behalf of. In some old design departments, such habits are still followed. That is to say, the standard is represented by DN ×× (B series), and the British system (A series) is expressed in inches. However, according to the current actual situation, the latter case Inch represents the nominal diameter, the general representative of the English series (A series) "is usually correct, but the first case is no longer accurate. The current more popular approach is. Regardless of the metric system in English are DN × × said.