Heat number
Encyclopedia
A heat number is an identification number that is stamped on a material plate after it is removed from the ladle
and rolled at a steel mill
.
Industry quality standards require materials to be tested at the manufacturer and the results of these tests be submitted through a report, also called a Mill Sheet or Mill Certificate. The only way to trace a steel plate back to its Mill Sheet is the Heat Number. A heat number is similar to a lot number
, which is used to identify production runs of any other product for quality control
purposes.
Ladle
Ladle may refer to:* Ladle , a serving device, typically for soup* Ladle , a foundry ladle used to carry and pour molten metal...
and rolled at a steel mill
Steel mill
A steel mill or steelworks is an industrial plant for the manufacture of steel.Steel is an alloy of iron and carbon. It is produced in a two-stage process. First, iron ore is reduced or smelted with coke and limestone in a blast furnace, producing molten iron which is either cast into pig iron or...
.
Industry quality standards require materials to be tested at the manufacturer and the results of these tests be submitted through a report, also called a Mill Sheet or Mill Certificate. The only way to trace a steel plate back to its Mill Sheet is the Heat Number. A heat number is similar to a lot number
Lot number
A lot number is an identification number assigned to a particular quantity or lot of material from a single manufacturer. Lot numbers can typically be found on the outside of packaging...
, which is used to identify production runs of any other product for quality control
Quality control
Quality control, or QC for short, is a process by which entities review the quality of all factors involved in production. This approach places an emphasis on three aspects:...
purposes.
Numerical significance
Usually, but not universally, the numbers indicate:- the first digit corresponds to the furnace number
- the second digit indicates the year in which the material was melted
- the last three (and sometimes four) indicate the melt number.