Ingots are large rough castings designed for storage and transportation. The shape usually resembles a rectangle or square with generous fillets. They are tapered, usually with the big-end-down.
Semi-finished solid metal form produced in a non-continuous casting process by pouring liquid metal into large molds. A steel ingot is usually rectangular in cross-section, weighs between 25 to 30 tons, and is rolled into blooms and billets (for making bars, rods, and sections) and slabs (for making plates, sheets, and strips). In a continuous casting process, the common practice is to directly cast the metal into blooms or billets.
A billet is a length of metal that has a round or square cross-section, with an area less than 36 in2 (230 cm2). Billets are created directly via continuous casting or extrusion or indirectly via hot rolling an ingot or bloom. Billets are further processed via profile rolling and drawing.
Billets are also known as bar stock.
USAGE OF SILICO MANGANESE :
Silico Manganese is used as a ladle addition to the liquid steel manufactured in Electric Arc Furnace steel making practice. Final chemistry with respect to Manganese and partly Silicon is achieved suitably for casting of Railway steel wheels. Non-metallic/slag/sand inclusions in the Silico Manganese results in the formation of slag and therefore, wheels thus cast will tend to have non-metallic inclusions causing rejection or rework. RWF has no facilities for secondary refining or vacuum degassing or Argon purging in the ladle.
CHARACTERISTICS OF RAW MATERIALS USED: The manufacturer/supplier has to disclose the details of the grade, source, specification and acceptance criteria of all raw materials used for manufacturing Silico Manganese to satisfy uses of the material as mentioned above.
CHEMICAL COMPOSITION :Chemical Composition will be in accordance with grade Si16Mn63 of IS 1470:1990 (Third Revision) as indicated below:
60 - 65%
14 - 17%
Ni, Cr & Mo
Particle Size : 40 – 150 mm, i.e., size designation 3 of Table 2 of IS 1470 : 1990 Size tolerance will be as per clause 8.1 and Table 2 of IS 1470 : 1990 including over-sizes and under-sizes.
The material shall be preferably free from extraneous contaminations like slag and non-metallic inclusions, etc.