WCO Explanatory Notes reproduced for reference. © World Customs Organization. Verify against official WCO publication.
72.01 - Pig iron and, Spiegeleisen in pigs, blocks or other primary forms. 7201.10 7201.20 - Non-alloy pig iron containing by weight 0.5 % or less of phosphorus - Non-alloy pig iron containing by weight more than 0.5 % of phosphorus 720 1.50 - Alloy pig iron; spiegeleisen (A) PIG IRON Pig iron is defined by Note 1 a) to this Chapter. However, chromium steels containing more than 2 % of carbon are by app ication of Note 1 (d) to this Chapter to be classified wlth the other alloyed steels in sub-chapter IV. I Pig iron is the main of the iron and steel industry, being produced principally b reducing and blast furnaces or by smelting ferrous waste and scrap in e ectric furnaces It is an iron-carbon alloy also containing other elements such as silicon, manganese, sulphur and hosphorus, derived from the ore, scrap, flux or fuel, and sometimes also other elements suc as chromium and nickel, added to impart special properties. r f The heading covers both iron which has been remelted for convenience and to obtain a certain de or alloying, provided the composition of the in the definition under Note 1 (a). Pig iron may be in metal remains within the the form of pigs, blocks, or not broken, or in the molten state, but the heading does not extend to shaped or worked articles (e.g., rough or finished castings or tubes). Pig iron is characteristically brittle and unworkable; this can be remedied to some extent by annealing which gives the product superficially some of the properties of steel, the product being known as " malleable cast iron ' (whiteheart or blackheart). In practice, the treatment is applied generally to cast articles, which are classified elsewhere, but any such material in the forms of pi s, blocks, etc., would fall in this heading provided the carbon content !:cz 2 % by we~g%t. Alloy pig iron is ig iron containing, by wei ht, one or more of the elements mentioned in Subheahng Note (a) in the proportions speci ed in that Note. P d (B) SPIEGELEISEN Spiegeleisen is defined in Note 1 (b) to this Chapter. It is sometimes considered in the trade as a ferro-alloy but is classified in the same heading as pig iron since it is generally obtained directly fiom ores. It is used principally in steel manufacture to de-oxidise and recarburise the iron, and for alloying. It shows a glittering surface on fracture because of the high manganese content, and is presented in the same forms as pig iron.
1.- In this Chapter and, in the case of Notes (d), (e) and (f) throughout the Nomenclature, the following expressions have the meanings hereby assigned to them : (a) Pig iron Iron-carbon alloys not usefully malleable, containing more than 2 % by weight of carbon and which may contain by weight one or more other elements within the following limits : - not more than 10 % of chromium - not more than 6 % of manganese - not more than 3 % of phosphorus - not more than 8 % of silicon - a total of not more than 10 % of other elements. (b) Spiegeleisen Iron-carbon alloys containing by weight more than 6 % but not more than 30 % of manganese and otherwise conforming to the specification at (a) above. (c) Ferro-alloys Alloys in pigs, blocks, lumps or similar primary forms, in forms obtained by continuous casting and also in granular or powder forms, whether or not agglomerated, commonly used as an additive in the manufacture of other alloys or as de-oxidants, de-sulphurising agents or for similar uses in ferrous metallurgy and generally not usefully malleable, containing by weight 4 % or more of the element iron and one or more of the following : - more than 10 % of chromium - more than 30 % of manganese - more than 3 % of phosphorus - more than 8 % of silicon - a total of more than 10 % of other elements, excluding carbon, subject to a maximum content of 10 % in the case of copper.