For sizes < 66cm, the circumference along the opening = 8-10 x Gape; For sizes > 66cm, the circumference = 6.5 x 7.5 x Gape. ... Cone Crusher Stone Grade Distribution. Gyradisk Cone Crusher. For finer size products (e.g., -6 mm), a special cone crusher known as the Gyradisc is commonly used. ... 2020 Mining Mill Operator Training | ...