Annealing is an umbrella term used in heat treating, which refers to the process of raising the temperature and controlled cooling of a material to change the properties. The annealing technique is applied to castings primarily to improve machinability by softening the material. This heat-treating process is used to turn pearlite into ferrite.

Annealing heat treatment is carried out for the grades: EN-GJS-400-15C, EN-GJS-400-18C-LT, EN-GJL-150C-A, EN-GJL-150C.