Reposting the information provided by Dajian Group regarding medium-speed coal mills for everyone’s reference!

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Medium-speed coal mills 　　 I. Leading technology in the grinding field. In 2001, China obtained the production license for the EM-type medium-speed coal mills from German company Claudius Peters (abbreviated as CP), which feature advanced 21st-century technology and hold a market share of over 40% in the international field of blast furnace coal injection. By combining Germany’s reliable and high-quality equipment with lower domestic manufacturing costs, these mills offer excellent performance per unit cost, serving domestic metallurgical enterprises. Over the past few years, more than 40 domestic enterprises have used this type of grinder in their blast furnace coal injection projects, achieving excellent results and receiving positive feedback from users. EM-type mills come in a wide range of specifications, with processing capacities ranging from 5 tons to 120 tons per hour, meeting the needs of grinding plants in steel plants, thermal power stations, cement factories, and other industrial sectors. EM mills can be used to grind coal, petroleum coke, gypsum, limestone, bentonite, clay, phosphates, and other minerals. II. Specifications and Models – Function Overview: Grinding, drying, separation, and conveying of materials are all carried out within the same device. The material is fed into the rotating grinding elements through a central feed pipe, where it is then evenly distributed between the grinding balls and rings. A hydraulic system is used to ensure optimal grinding pressure under all operating conditions. The material after grinding is accelerated outward along the concave edges of the grinding ring, and then, carried by the hot air flow, it is dried evenly and transported to the separator above. During this process, the larger particles fall back into the grinding mechanism. The fine particles flow toward the separator. The separator ensures that powders of a specific fineness leave the grinder, while particles that are too large are sent back for further grinding. Both static and dynamic separators are specifically designed for grinders, and can be selected according to the desired particle size specifications. III. Performance Features ● “Marathon runner” – long lifespan. The design concept for grinding is based on a large-volume axial spherical bearing. The grinding ball can roll freely between the upper and lower grinding rings. The grinding balls and rings are made from wear-resistant materials using advanced foreign manufacturing techniques, ensuring a long service life. ● Stable output: The special geometric shape of the grinding mechanism ensures that the grinding area remains constant throughout its service life, thus maintaining the same output at both the beginning and end of use without any decline. ● The wear is even and regular; the grinding ball maintains an absolutely circular shape throughout the wear process. ● The grinding elements require no maintenance. The grinder’s interior is hot and filled with dust, and there are no bearings that need lubrication. The grinding element requires no maintenance during its service life. ● It has a low air leakage rate and good safety features. When designing the mills, the staff at the German company CP implemented various sealing measures to strictly control the air leakage rate of the mills. The air leakage rate of EM-type mills is ≤2%. When grinding bituminous coal or mixed coal, it is easier to control the O2 level, thereby facilitating safer production. The shell of the EM type mill is designed in accordance with the bridge design standards specified in German DIN standards, and it can withstand a pressure of 0.35 Mpa. ● The hydraulic and lubrication systems are simple. A hydraulic system is installed to increase the grinding pressure, and the accumulator allows the hydraulic pump to operate only once after a long period of time. The EM type mill is equipped with a lubrication system only for the reducer. ● No-load test run: After the grinder is installed, a no-load test run can be carried out without feeding any material in. ● Start under load: After an emergency stop, it is possible to start the mill directly under load without first removing the material inside the mill. The material can also be ground to perfection before the mill stops, thereby ensuring the best level of safety when the mill comes to a halt. The mill motor is a specially designed motor with high starting torque. ● Power saving: The structural characteristics of the grinder result in the motor power required for this grinder being 1–2 grades lower than that of other grinders with equivalent capacity. ● Low noise: The noise level of the grinder meets the relevant ** standards; the noise level 1 meter away from the grinder is ≤85 dB. ● Spring mechanism: This grinder can handle foreign objects without requiring shutdown. When the grinding balls or rings come into contact with these obstacles, the resulting vibrations are completely absorbed by the tension springs, which protects the grinding components and reduces the impact on the hydraulic system. ● Slag removal: The grinding balls automatically remove hard foreign objects such as coal rods and stones from the track of the grinding ring, while scrapers convey these foreign objects to the waste bin. The self-locking design of the slag discharge mechanism enables the mill to discharge slag while it is in operation. ● Easy to install and maintain: The EM type mill comes equipped with a set of installation and maintenance lifting tools. The installation order is: lower shell, middle shell, upper shell, inlet and outlet pipes, etc. Then open the middle housing door, install the maintenance lifting device, and lift the internal components in one by one for installation. When servicing or replacing the grinding parts, open the main door, install a lifting device, and lift out the internal components one by one. Thus, installation is convenient and fast. IV. Selection and design: victory: