We study the patterns of variations in chemical composition for a large number of commercial melts of three grades of pipe steel: 17G1S-U, 10G2FB, and 12G2Sb via statistical clustering of experimental data. A comparative structural study was performed; the effects of various steel alloy components on the amount, distribution, and morphology of the pearlite component; the size and shape of the ferrite grains; and the development of dynamic recrystallization processes.