§ 420.71 Specialized definitions.

(a) The term hot forming means those steel operations in which solidified, heated steel is shaped by rolls.

(b) The term primary mill means those steel hot forming operations that reduce ingots to blooms or slabs by passing the ingots between rotating steel rolls. The first hot forming operation performed on solidified steel after it is removed from the ingot molds is carried out on a “primary mill”.

(c) The term section mill means those steel hot forming operations that produce a variety of finished and semi-finished steel products other than the products of those mills specified below in paragraphs (d), (e), (g), and (h) of this section.