Billet

Steel billets are semi-finished products of steel production at the second stage. Usually they are taken out directly during the casting process of steel. They are produced in a square cross-section of area less than 230 square cm. Their final products involve bars, rods, tubes, pipes, wire and wire products.

Steel bars are considered as the long products of billets. The surface of the carbon steel billet is rough and the ends may be deformed by shearing. Billets are typically used as feedstack for rolling wire rod or bar and can be used in certain forging applications.

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On corrosionpedia a billet is defined as : "A billet is a section of metal used for rolling into bars, rods and sections. It can be produced with ingots or directly by continuous casting. Billets are used as raw materials or feedstock in extrusion, forging, rolling and other metal-processing operations. Billets have limited use before they have been formed into more functional shapes and sizes. They must undergo a series of manufacturing processes before they can be used for various purposes. The unformed billets, however, can be used in striking currency such as coins and as reserves, similar to gold bars. Final products also include bar stock and wire. Centrifugal casting is also used to produce short circular tubes as billets, usually to achieve a precise metallurgical structure. Billets have a specific grain structure, which enables the metal to be processed more intricately. Steel billets are also known for their malleability and ductility, especially when exposed to varying temperatures during shaping and molding. Proper casting of billets is important because it determines the billet's strength and flexibility. Billets undergo a number of tests before they are sold. Billets that develop cracks and voids between heating and cooling processes are rejected, as such defects make the product useless."

Some typical dimension for square billet are: nominal size 100 - 160 mm, length 6.0 - 12.0 m. The specifications for billet delivery are: section dimension, length, rhombodity, corner radius, straightness, bending, angular twist and surface perfection (such as longitudinal cracks, transverse cracks, holes etc.).