Bulb flat steel is a kind of special section steel, which is composed of flat web and spherical ball head. Bulb flat steel is mainly used in shipbuilding and bridge construction. However, with the rapid development of shipbuilding industry in recent years, it has gradually become the special name of marine bulb flat steel, and is the most important type of marine section steel. It is mainly used as the stiffener of ship plate, equivalent to the "rib" of human.
At present, the domestic standard for bulb flat steel is GB/T 9945-2001 "hot rolled bulb flat steel", and the European standard en10067: 1996 "hot rolled bulb flat steel" is adopted non equivalently. The specification is consistent with the European standard, but the tolerance range of the European standard is modified, and the material requirements are added.
The specification of bulb flat steel is generally divided according to the nominal width. The minimum specification is 8 mm (i.e. the nominal width is 80mm), and the maximum specification is 43 mm (the maximum nominal width is 430mm). There are 2-5 different thicknesses for each specification.
