Pulverizers are mechanical devices used for crushing and grinding. Pulverizers provide size reduction services for a number of different industries, including construction, agriculture, industrial manufacturing, power generation, pharmaceutical products development, printing, and material processing. Just some of the materials they can consume include brick, coal, concrete, limestone, paper, plastic materials, and wood.
Typically, pulverizers are sorted into three major groups: grinding mills, crushers, and impactors.
Grinding mills break down materials using friction, which they generate via grinding media. Any number of coarse materials may serve as grinding media, but some, such as brass, bronze, ceramics, flint, and non-sparking lead, are more common than others. The two most utilized types of grinding mills are hammer mills and ball mills. Hammer mills are primarily used on farms, where they grind chaff and grain using vertically revolving hammers that are encased in steel.
Ball mills, on the other hand, grind material using steel rods, steel balls, or similar media. The mills themselves are quite simple, consisting of a horizontally-mounted rotating cylinder and liners that protect the cylinder from wear and tear. To work, the media is placed inside the cylinder, where it is tossed or tumbled.
Similar to ball mills are tube mills, the names of which are sometimes used interchangeably. Tube mills also consist of a revolving cylinder and liners, but they are typically larger and use media that is mixed with water to achieve fine pulverization. This media feeds in at one end, and is passed out the other as slurry. Read More…
Next, crushers are used to crush large, dense materials like rock and stone, until it is dust or gravel. Usually, they are used to simplify the differentiation of materials or to reduce materials and/or prepare them for recycling or disposal. The most common type of crusher is the jaw crusher, which features one stationary jaw and one mobile jaw.
Jaw crushers can be classifications based on the position of the pivoting of their mobile jaw, also called a swing jaw. These classifications include: Blake crushers, characterized by a swing jaw fixed at the upper position, Dodge crushers, characterized by a swing jaw fixed at the lower position, and Universal crushers, characterized by a swing jaw fixed at the intermediate position.
Finally, impactors are quite like crushers, except that they reduce materials differently. Instead of crushing, which uses pressure generated by two opposing forces, they use impaction, a process that transmits force via collision. To carry out impaction, impactor, or impact crushers, contain the material to be crushed inside a cage, with which they facilitate collisions. As the material gets smaller, it falls out of openings on the bottom, side, or end of the cage.
Along with the above common pulverizer types are those types that are less common, but more specialized, such as gyratory crushers, cone crushers, MPS mills, and bowl mills.
Gyratory crushers provide either primary or secondary crushing of extracted materials in ore or mine processing plants. They are quite similar to jaw crushers, in that they both have conical heads and concave surfaces that are typically lined with manganese steel. However, instead using rotational movement, as jaw crushers do, gyratory crushers achieve their ends using eccentric, or off-center, motion.
Cone crushers are quite a lot like gyratory crushers, and are also used in mining, though they are more commonly used for secondary crushing only. They work best with mid-hard to above mid-hard ore and rocks. Their crushing chamber is also less steep than that of the gyratory crusher. Cone crushers work by squeezing materials between their bowl liner and mantle, which is mounted on an eccentrically-gyrating spindle.
Here, they descend as they are continually broken, until they are small enough to fall through a narrow opening at the bottom of the crusher. Cone crushers can be divided into four groups: compound cone crushers, also called VSC series cone crushers, Symons cone crushers, or spring cone crushers, single cylinder hydraulic cone crushers, and multi-cylinder hydraulic cone crushers.
Next are MPS mills, also known as applied force mills or vertical spindle roller mills. MPS mills use tires as their grinding media. They primarily pulverize coal, which is piped onto a grinding table via a central feed pipe, where the tires can roll over it. Likewise, bowl mills use tires to crush coal. They are available in two main configurations: shallow bowls and deep bowls.
Pulverizers can also be divided into groups of low speed, medium speed, and high speed machines. Those in the low speed group include ball mills and tube mills, while the medium speed group contains ring and ball mills, MPS mills, and bowl mills. Finally, high speed pulverizers include attrition mills and jet pulverizers. Different speed pulverizers are suited to different applications, which range from pulp and paste creation, to medication grinding, to concrete crushing.