This national standard specifies the cross-sectional shape, sectional dimension, weight and tolerance, length and tolerance, shape or marking illustration of the hot-rolled steel bars (round steel bars, square bars, flat bars, hexagon steel and octagon steel).
This Standard is applicable to hot-rolled round bars in diameter of 5.5mm~310mm and hot-roll square bars in side length of 5.5mm~200mm; hot-rolled flat bars in thickness of 3mm~60mm, in width of 10mm~200mm, with rectangular sections, and for general purpose; hot-rolled hexagon steel in across flats distance of 8mm~70mm and hot-rolled octagon steel in across flats distance of 16mm~40mm; hot-rolled tool steel flat bars in thickness of 4mm~ 100mm, in width of 10mm~310mm and with rectangular sections.
