I have the strength numbers, too. Q195 and Q235 are 195 and 235MPa yields. 20 (>245MPa yield)is supposed to be comparable to 1020 (350MPa yield), and is used in seamless tubing. Q235 will work harden rather than bend, and is ng for shaping tubes. For the chinese steels I have information on, their yield numbers are low compared to simpler US carbon steels. Are the numbers accurate? Are there qualities of strength that are not in the numbers? (I am no metalurgist) Anyone able to shed a bit of light here? thanks, all.