The invention relates to a vertical roller mill comprising a grinding table

The invention relates to a vertical roller mill (hereinafter referred to as of the type described) comprising a grinding table that is rotatable about a vertical axis; no less than two grinding rollers which are rotatable about substantially horizontal, stationary axes, and are urged against an annular grinding path in the grinding table; in addition to a nozzle ring encircling the table for blowing separating and conveying, and possibly drying, gas into a mill housing above the grinding table.

Sand making machine (VSI-crusher) is used in several applications for crushing tough material like rocks, ore, and so on. WO 2004/020103 describes a sand making machine comprising a housing in addition to a horizontal rotor located inside the housing. Material that may be to become crushed is fed vertically in to the rotor through a hopper, a feeding chamber and a feed tube. Using the aid of centrifugal force the rotating rotor ejects the material against the wall of the housing, and on impact with the wall the material is crushed to a desired size.

Replacement from the feed tube, which can be a put on part, is definitely an high-priced, complex, and time consuming operation, normally involving lifting an upper portion from the crusher, which includes the hopper, with a crane.

Simplifying the replacement of a feed tube could strengthen the continuous use of a vertical shaft influence crusher.

An exemplary vertical shaft influence crusher comprises a rotor that rotates about a substantially vertical axis for accelerating a flow of material to become crushed; a housing comprising a circumferential influence wall section against which the accelerated flow of material could possibly be crushed; a feed tube for vertically feeding a flow of material in to the rotor to be crushed; a feeding chamber for vertically feeding a flow of material in to the feed tube, wherein the feeding chamber incorporates a feeding chamber side wall; plus a initially door for opening and closing a first aperture within the feeding chamber side wall, wherein mentioned feed tube is removable from said feeding chamber via mentioned first aperture.

Within a crusher in the above kind, the feed tube could possibly be replaced by means of the very first aperture. This allows for any significantly easier replacement process, without the need of the will need for removing a hopper or any other structure mounted above the feeding chamber.