The nominal pipe diameter DN, which is also known as the nominal connection diameter or simply the nominal diameter, indicates the approximate internal diameter of a pipe in millimetres (mm). The nominal pipe diameter is given without a unit in DN (French: diamètre nominal). Many companies also use the specification in inches. The nominal sizes for medium and heavy threaded pipes are specified in DIN EN 10255. The outside diameter of a pipe is used for direct measurement on site, as shown in Table 1.
You are here: / Archives for Basics