A scalper: is equipment used upstream of a separation process to remove the finest particles that are sometimes harmful to the rest of the process. more simply, it is a kind of screen that can accept blocks of stone sometimes weighing several tons and intended to remove particles smaller than 80-100mm before directing them to a crusher. They are generally equipped with diverging bars and not grids and are often the first piece of equipment in a separation unit; they are placed in the primary.
A crusher: is equipment used to reduce the size of the aggregates, depending on the grinding technology, the materials, the flow rate, it will have more or less of an effect on this reduction.
A hammer: it is a type of crusher / grinder. There are 2 types of hammers: vertical axes and horizontal axes. The vertical axes are often called form correctors, and the horizontal axes take the name of strikers. The technology is quite simple, the product to be crushed enters the crusher from the side and meets a horizontal rotor equipped with beaters. The beaters collide with the rocks and project them onto projection surfaces called curtains. you can adjust the fineness of crushing by adjusting the distance between the curtains and the rotor. depending on the applications and types of rock, these crushers can be equipped with 2 or 3 curtains. The curtains are closer and closer to the rotor so that we speak of crushing stages.
a screener: and a generic name little used, we will speak either of screens or of sieve. The limit of these 2 equipments being generally located at a screening or sieving of 10mm. from 0 to 10 mm we will speak of a sieve beyond a sieve. These equipments are used to carry out a separation of products which enter the equipment according to the size of the particles. this separation is possible thanks to the combined effect of the vibration provided by a mechanical excitation and a screening grid. There are several types of vibration, grids, machine inclination, and necessarily budgets.
