A billet is semi-finished steel with a square or rectangular section, produced by electric arc furnace and continuous casting. It is the input for rebar, wire rod and section production in rolling mills.
What matters in a billet is not the size but the analysis: the chemical composition determines which grade it will give once rolled.
Technical specifications
| Section | 100×100 – 150×150 mm |
|---|---|
| Length | 3,000 – 12,000 mm |
| Grade | 20MnB4, Q235, 5SP / 3SP |
| Production | Electric arc furnace + continuous casting |
| Analysis | With a cast certificate |
| Use | Rolling mill input |
Why the cast certificate is essential
The cast certificate shows the chemical analysis of the billet: carbon, manganese, silicon, sulphur, phosphorus and any alloying elements.
Without that analysis a rolling mill cannot know what grade the bar it produces will reach. A billet whose analysis is not documented is an unpredictable input.
The grade codes
5SP and 3SP describe semi-killed steel grades and are used in general-purpose rebar production.
20MnB4 is a boron-alloyed grade preferred where hardenability is required. Q235 is the structural steel equivalent.
Holding billet in a bonded warehouse
Because the duty burden on billet imports is high, the warehousing procedure is particularly useful for this product: duty is deferred until withdrawal.
As much billet as the mill will process that month is withdrawn and the rest of the consignment waits in the warehouse. This is one of the methods that eases working capital the most.