CPC Subgroup
C21D 9/085 Full Title
Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor > for tubular bodies or pipes
C21D 9/085 Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor > for tubular bodies or pipes