Vertical mill, roller mill, mechanical term name for roller grinding (rolIer mill), also called grinding machine. Because the mill is standing type, used to call its vertical mill, vertical mill for short. Vertical mill set crushing, grinding, choose powder, drying, conveying and other functions in one, is the cement, chemical, coal, electricity and other departments widely used a kind of grinding equipment.
Vertical grinding mill in working principle, mechanism, mechanical structure, the system performance in the cement industry at home and abroad with its unique advantages more and more get the attention, with the birth of the kiln outside the decomposition technique, the cement industry increasingly uses vertical grinding machine grinding of cement raw material and clinker, compared with the traditional ball mill vertical grinding machine has the following features.
(1) high grinding efficiency. Vertical mill adopting the principle of layer crushing, grinding materials, its efficiency is about 165% of the ball mill; Low energy consumption, lower power consumption than ball mill grinding system by 20% ~ 30%, and with the increase of the raw water, the electricity saving effect is more significant; Individual output.
(2) the drying ability. Powder material suspended in air, the large heat transfer area, high thermal efficiency. Within the vertical grinding materials can be drying up to 15% moisture content.
(3) product grading are neat, short staying time within the vertical mill, to adjust the final composition. Material stay time in vertical mill only 2 ~ 3 min,, and in the ball mill tends to stay for 15 ~ 20 min. So the vertical mill product chemical composition and fineness can quickly determine, correction, easy to realize intelligent, automated operation.
(4) technological process is simple, cover an area of an area, and take up the space is small. Vertical mill itself with classifier, using the gas conveying material, do not need to add classifier and the improvement of transmission materials grinding machine, the grinding dust gas can be directly by the high concentration bag dust collector or collected by electric dust collector, so the process is simple, layout is compact, and can open layout. Construction area of about 70% of the ball mill system, architectural space as 50% ~ 60% of the ball mill system.
5. Low noise, less dust, clean operating environment. Vertical grinding roller and grinding disc at work don't direct contact, no ball mill ball in the collision, the clang of lining board of the steel ball impact each other, so the noise is small, 20 ~ 25 db lower than the ball mill. In addition, the vertical mill adopts full sealing system, the system under the negative pressure operation, no dust, clean environment.
6. Less wear of grinding media, high utilization rate. Due to vertical mill operation had no direct contact between metals, therefore, less wear of the grinding media, abrasion per unit product for 5 ~ 10 g/t.
All landowners grinding of hard and abrasive materials, short service life of lining board, maintenance is more frequent and more expensive than wear a ball mill. But rather than replaced the ball mill, classifier, hoist equipment such as compared to the total amount of maintenance, the maintenance quantity is still small.