The degree to which material is reduced through stages of primary, secondary, and tertiary crushing can depend on the type of material, like aggregate, concrete, and asphalt, and can also depend on the variety of output sizes needing produced.
Primary Sinter Crusher For Primary and Secondary Crushing … Specially-designed Single Roll Crushers are utilized as Sinter Crushers with regard to primary crushing within the iron and metal industry. Double Roll Crushers are … Crushed stone – North Carolina Geological Survey Home Page
Roll crushers are generally not used as primary crushers for hard ores. Even for softer ores, such as chalcocite and chalcopyrite, they have been used as secondary crushers. Choke feeding is not advisable as it tends to produce particles of irregular size. Both open and closed circuit crushing is employed.
The secondary crusher is mainly used to reclaim the primary crusher product. The crushed material, which is around 15 cm in diameter obtained from the ore storage, is disposed as the final crusher product. The size is usually between 0.5 and 2 cm in diameter so that it is suitable for grinding.
HSI crushers can be primary or secondary crushers. In the primary stage, HSIs are better suited for softer rock, such as limestone, and less abrasive stone. In the secondary stage, the HSI can process more abrasive and harder stone.
The output of the primary crusher is fed to a secondary crusher, which further reduces the size of the material. Similarly the output of secondary crusher is fed to the tertiary crusher which reduces the material size further. Some of the materials may pass through four or more of the crushing stages before it is reduced to the desired size.
A gyratory crusher is one of the main types of primary crushers in a mine or ore processing plant. Gyratory crushers are designated in size either by the gape and mantle diameter or by the size of the receiving opening. Gyratory crushers can be used for primary or secondary crushing.