There are mainly the following specifications: the smallest specification in China is DN80, and the cost of a smaller specification than DN80 is too high, and generally welded pipes are used instead. Then other common specifications are DN100, DN150, DN200, DN250, DN300, DN350 (this specification is not often used), DN400, DN500, DN600, DN700, DN800, DN900, DN1000, DN1200.

Specifications larger than DN1200 generally need to be ordered in advance, and there are relatively few manufacturers with stocks. Generally, there are specifications such as DN1400, DN1600, DN1800, DN2000, DN2400, and DN2600.