The characteristics of raw materials required for the cement production differ at a wide range. The limestone deposits used today as base material, show very different properties regarding hardness, abrasiveness and stickiness. To optimize the crushing process as well as the investment and operating costs, different types of crushers are available. To make a proper selection, several important points should be considered in advance.
limestone impact crusher
With the introduction of vertical roller mills, which accept a raw material size of up to 80mm, the Impact Crusher became of prime importance for the cement industry. Modern Impact Crushers are equipped with heavy duty rotors in common rail design. Specially designed cast discs are combined on one main shaft, concentrating the main weight at the circumference of the rotor. The result is a high moment of inertia and kinetic energy, which allows one-step crushing of the raw material down to the required product size.
State-of-the-art Impact Crushers are equipped with hydraulically supported impact walls and grinding path, allowing a calibration of the crushing gap and the product size according to the requirements. Therefore one crusher can be sufficient to produce limestone with a grain size of 0/80mm for the raw mills and a grain size of 0/35 mm as additive for the cement mills. To meet the problem of having uncrushable material like e.g. tramp iron in the feed material, each Impact Crusher should be equipped with an effective overload protection.