The expression method of steel pipe wall thickness grade, the expression method of the steel pipe wall thickness grade series is different in different standards.
There are three main representation methods:
1. Expressed by pipe table number (Sch);
2. Expressed by tube weight;
3. Expressed by steel pipe size.
1. Expressed by pipe table number (Sch):
For carbon steel pipe wall thickness, there are 10 grades: Sch10, 20, 30, 40, 60, 80, 100, 120, 140, 160, etc. (If S is added after the number, it means stainless steel pipe);
For stainless steel wall thickness series, there are four grades: 5S, 10S, 40S, and 80S.
2. Expressed by tube weight, such as STD (standard weight), XS (thick tube), XXS (extra thick tube)
3. It is expressed in terms of steel pipe wall thickness, that is, "pipe outer diameter × wall thickness", such as φ89X4.