What is the primary application of steel bulb flats?

They are predominantly used as stiffeners for steel plates in ship hulls, marine environments, and sometimes in bridge decks.

How is the mass of the bulb flat section calculated?

The sectional mass and properties are calculated assuming a standard steel density of 7.85 g/cm³.

Where can I find the dimensional tolerances for these sections?

General rolling and cutting tolerances for structural steel sections are typically governed by cross-referenced standard IS 1852.

IS 1863

: 1979

rolled steel bulb flats

CurrentSpecializedSpecificationBIMStructural Engineering · Structural Engineering and Structural Sections

Download PDF BIS Portal Google

This standard specifies the nominal dimensions, mass, and sectional properties of hot-rolled steel bulb flats, which are highly specialized sections primarily used as plate stiffeners in shipbuilding and structural engineering.

rolled steel bulb flats

Quick Reference Values

mass density of steel7.85 kg/dm³ (or g/cm³)

common depth range80 mm to 430 mm

Practical Notes

Bulb flats offer excellent strength-to-weight ratios and their rounded edges make them easier to paint and maintain against corrosion compared to standard angle sections.

Because bulb flats are highly specialized, structural engineers should verify availability and minimum order quantities with steel mills before specifying them for general building structures.

Sectional properties provided in this standard are essential for structural steel detailing and creating accurate BIM profiles.