• This part of ISO 630 specifies the technical delivery requirements for hot-finished hollow sections of circular, square • or rectangular form. It is applicable to hollow sections formed hot with or without subsequent heat treatment or • formed cold with subsequent heat treatment to obtain equivalent metallurgical conditions to those obtained in the • hot-formed product. Fine grain steels are generally delivered in the normalized condition. • The grades, chemical composition and mechanical properties for non-alloy steels and fine grain steels are given in • annexes A and B, respectively. • NOTE 1 Requirements for tolerances, dimensions and sectional properties are given in ISO 657-14. • NOTE 2 For the technical delivery requirements of hot rolled structural steels in other product forms, e.g. plates, wide strip, • flats, bars and other structural sections, see ISO 630:1995. • NOTE 3 For cold-formed structural hollow sections, see ISO 10799.