Crushers are just one of the many types of equipment used for
size reduction. Crushers reduce larger sized, very hard feed
material between two surfaces in a crushing or shearing action
versus impact mills and pulverizes, or grinding type ball or bead
mills.
Crushers are often seen in mining operations and are used for
crushing hard rock, and coal. In Mining Operations Crushers can
be designed to crush 3”**5” Inch diameter rocks into smaller
pieces 6” (Primary Crushing), and then again from 1/4” pieces
even smaller (Secondary Crushing).
The main types of crushers include:
Gyratory Crushers: This consists of a cone shaped pestle
oscillating within a larger cone-shaped mortar or bowl. The
feed material enter through the top wide section of the cone
shaped bowl. The angles of the cones are such that the width of
the passage decreases toward the bottom of the working faces
crushing the feed material into smaller pieces as it descends
down through the crusher.
Cone Crushers: This is a version of a gyratory crusher
having a very wide angle cone shaped pestle with a mortar or
bowl that has sides that are more parallel for a finer
crushing.
Jaw Crushers: Designed to crush material between two
plates or jaws. The different types of jaw crushers are
classified by where the jaws pivot – the Blake type pivots at
the top; the Dodge type pivots at the bottom; the Overhead
eccentric hinged at the top with the movable jaw suspended on
an eccentric shaft.
Roll Crushers: Roll crushers can consist of a single
roll or multiple rolls mounted in a housing. The feed material
is crushed either between the two rolls or in a single roll
machine between breaker bars mounted in the housing and the
rotating roll.
