Jaw Crushers

Jaw crushers are an extremely common type of primary compression type crusher used in surface and underground crushing plants. They consist of a wedge or v shaped space between a fixed jaw and moveable jaw. The moving jaw of a single toggle crusher moves elliptically (compression and attrition) while the double toggle crusher moves nearly perpendicular to the stationary jaw (pure compression). The crushing force is produced by an eccentric shaft which is either attached directly to one end of the moveable jaw (single toggle) or attached via an arm and toggles (double toggle). To compensate for heavy loadings and to store energy on the idling half of the stroke the eccentric shaft has attached heavy centrifugal masses (flywheels/pulleys). Final material size and production capacity is controlled by the size of the discharge opening (set) and and jaw pattern. The walls of the crushing zone are made of replaceable wearing jaws and are available with different surface patterns for different crushing applications.

Jaw crushers are used as primary crushers where throughput does not exceed 600 to 900 tons per hour. They offer simplicity of operation/maintenance and low head clearance for underground operation. These crushers are limited to material sizes not exceeding the opening at the top of the jaws and also require some type of feeding system.

- Shanghai Zenith Company, P.R. Engineering Ltd, Metso Minerals images.