Tubular mill for grinding natural and synthetic raw materials in particular for the cement industry

A tubular mill for grinding natural and synthetic raw materials, comprising:

• a rotary cylindrical drum having a horizontal axis and at least two grinding chambers containing grinding elements in which at least one grinding chamber contains grinding elements comprising a roller which when in an operating position has an axis of rotation thereof essentially parallel to the axis of said drum and an independent first external pressure support which supports said roller, said roller being idle and, at least along one of its outer generating lines, engaging an annular grinding track rigid with the inner wall of said drum, wherein said external support comprises an extraction support movable by an actuator element for extraction of said roller, and a feed mouth having said drum provided at one end of said feed mouth for the material to be ground and said drum having a local aperture introducing one of ventilation air and ventilation gas, and a first duct provided at a second end of said drum for discharge of the ground material and a second duct withdrawing said one of said ventilation air and said ventilation gas, and
• an adjusting mechanism provided between said two grinding chambers, said adjusting mechanism advancing the material which flows inside said drum.