At the enterprise, beds and other large-sized cast iron parts undergo both artificial and natural aging. On a special site in the open air, the beds are "matured" for more than a year. This allows stress relief after pretreatment without reducing the overall structural hardness of the cast iron.
So the next batch of frames after two years of natural aging went for further processing. They will be used in the production of machine tools with high precision requirements.
Usually, 50-70 units undergo natural aging. This stock is constantly renewed.