Seamless steel pipe 20# means

Seamless steel pipe 20 # () represents the meaning of seamless steel pipe is the product name, generally used to distinguish the welded pipe (with seam pipe).
20#, a steel grade, also called steel grade, is a chemical composition.
In general, 20# steel has the following chemical composition: Carbon (C) Silicon (Si) Manganese (Mn) Phosphorus (P) Sulfur (S) 0.17-0.24 0.17-0.37 0.35-0.65 0.35max 0.35max Different standards for chemical The ingredients are slightly different. Some standards also require chromium (Cr) molybdenum (Mo) 矾 (V) nickel (Ni) ...