Bar & Rod Rolling

Bar and rod rolling transforms continuously cast billets or blooms into the long products that form the backbone of the construction and engineering industries — reinforcing bar (rebar), wire rod, merchant bar, and special bar quality (SBQ) steel. Unlike flat products (strip, plate), long products are rolled in multiple passes through a series of oval, round, or shaped grooved roll pairs, progressively reducing the billet cross-section while elongating the product.

A typical bar mill processes billets of 100–160 mm square section and 6–12 m length, charged at 1,100–1,200 °C, through 16–28 rolling passes in three sequential mill groups — roughing, intermediate, and finishing — before the product exits as rebar (8–40 mm diameter), merchant bar (angle, flat, channel), or SBQ bar (round, square, hexagonal) for machining into engineering components.

A rod mill (wire rod mill) is a specialised, high-speed evolution producing coiled wire rod of 5–20 mm diameter at exit speeds of 100–120 m/s (430 km/h) — among the highest speeds in any industrial manufacturing process. The rod exits through a Stelmor conveyor for controlled air cooling, or through a water box and laying head for in-line quench-and-self-temper (QST) processing.