1.1 Melting analysis
Melting analysis refers to taking sample ingot during pouring molten steel and then making it into sample for chemical analysis. The analysis result represents the average chemical composition of the same furnace or tank of molten steel.
1.2 Product analysis
Product analysis refers to taking sample from the processed finished steel (including steel billet) for chemical analysis. Product analysis is mainly used for checking the chemical composition, so it is also known as check analysis. As a result of uneven distribution (segregation) of element produced in the crystallization process of molten steel, the value of product analysis is different from that of melting analysis.
1.3 Permissible variation for product analysis
Permissible variation for product analysis refers to that the value of melting analysis is within the standard scope but the value of product analysis may beyond the standard composition scope due to the element segregation in steel. A specified permissible value beyond this scope is namely the permissible variation for product analysis.
