scope:

This Standard specifies the appearance, shapes and permissible variations thereof, and the dimensions, mass and their tolerances of hot rolled steel sections (hereafter referred to as steel sections).

The application of this Standard shall be as specified in each product standard.

NOTE The International Standards corresponding to this Standard and the symbol of degree of correspondence are as follows.

ISO 657-1 : 1989 Hot-rolled steel sections - Part 1 : Equal-leg angles - Dimensions

ISO 657-2 : 1989 Hot-rolled steel sections - Part 2 : Unequal-leg angles - Dimensions

ISO 657-5 : 1976 Hot-rolled steel sections - Part 5 : Equal-leg angles and unequal-leg angles - Tolerances for metric and inch series

ISO 657-11 : 1980 Hot-rolled steel sections - Part 11 : Sloping flange channel sections (Metric series) - Dimensions and sectional properties

ISO 657-15 : 1980 Hot-rolled steel sections - Part 15 : Sloping flange beam sections (Metric series) - Dimensions and sectional properties

ISO 657-18 : 1980 Hot-rolled steel sections - Part 18 : L sections for shipbuilding (metric series) - Dimensions, sectional properties and tolerances

ISO 657-19 : 1980 Hot-rolled steel sections - Part 19 : Bulb flats (metric series) - Dimensions, sectional properties and tolerances

ISO 657-21 : 1983 Hot-rolled steel sections - Part 21 : T-sections with equal depth and flange width - Dimensions (overall evaluation : MOD)

In addition, symbols which denote the degree of correspondence in the contents between the relevant International Standard and JIS are IDT (identical), MOD (modified), and NEQ (not equivalent) according to ISO/IEC Guide 21-1.