Used Mill equipment

Mills
Industrial mills are used to reduce the size of a product by breaking or grinding into smaller granules or powder. There are many different types of mills that each correspond to specific industrial needs. The type of mill chosen should depend on the material and size of the feed material as well as the desired size of the final product. Special Projects International offers used industrial mills from well-known manufacturers like Automatic Equipment Manufacturing, Beardsley and Piper, Bepex Schugi, BICO Inc., Buffalo Hammermill Corp., Buhler, California Pellet Mill, Charlotte, Chicago Boiler, Cincinnati Muller Co., Eiger Machinery, Eirich, Entoleter, Ferrell-Ross, Ferro-Tech, Fluid Energy, Fitzmill, Fitzpatrick Co., Gifford-Wood, Holmes, J.H. Day, Krima, Lancaster, Libco, Meprotec, Netzsch, Prater Pulverizer Co., Premier, Quadro Comil, Restch, Richard Sizer, Rosskamp, Sanken, Simpson Mixer, Sonic, Sprout-Waldron, Stewart Bolling, Sturtevant, Sweco, Szegvari Union Process, U.S. Stoneware, Wiley, and more. The types of industrial mills we offer are listed and described below.

Horizontal Media Mill
Horizontal media mills usually consist of an agitator shaft with disks in the center of a pressure-sealed horizontal tubular grinding chamber. The mill is loaded with small spheres or beads and then activated by a high-speed agitator which separates the individual solid particles. As the feed material is pumped through the mill, the agitator shears and crushes the feed material into smaller particles. Horizontal media mills are commonly found in several industries including paints, inks, coatings, cosmetics, pharmaceuticals, food products, and other specialty chemicals.

Hammer Mill
Hammer mills are machines designed to shred or crush aggregate material into smaller pieces by the repeated blows of hammers. These machines consist of a steel drum that contains a rotating shaft or drum on which hammers are mounted. The rotor is spun at a high speed inside the drum while material is fed into a feed hopper. As the material comes in contact with the rotating hammer bars, it is shredded/grinded then discharged at the outlet. Additionally, there is usually a screen fitted at the bottom of the mill to hold bigger solid particles while allowing the properly-sized particles to pass through as finished product. Hammer mills are commonly used for material processing in the food, construction, chemical, and cosmetic industries.

Fitzmill
Fitzmills are a type of hammer mill designed by Fitzpatrick Co. specifically for high-precision particle size reduction. The customizability and precision of the FitzMill is what sets it apart from other hammer mills. FitzMills can be used in coarse grinding and chopping of dry material, size reduction of wet material, de-lumping of agglomerated material (wet and dry), pulverizing, solid/liquid blending, granulating compacted material, processing slurries and liquids, pureeing and emulsifying, processing and conditioning wet and dry materials, and more.

Sand Mill
Sand mills are industrial machines that are designed to grind a given material into very small particles of roughly equal size. Sand mills consist of a grinding chamber with an agitator shaft that is fitted with several impeller disks which are used to shake the media. The mills are provided with a jacket arrangement to cool the ground material in the grinding chamber. As the material is pumped from the bottom up through the grinding chamber, it receives high shear forces between the grinding media which results in fine grinding of the product. Some sand mills are equipped with re-capture systems, allowing operators to pass the mixture through the sand mill more than once to make the product finer and more even. Sand mills are commonly found in the paint and chemical industry.

Colloid Mill
Colloid mills are machines that are designed to reduce the particle size of a solid in suspension in a liquid, or to reduce the droplet size in emulsions. It can also be used to reduce the particle size of solids in suspension. A high speed rotor pushes the fluid through small holes in a stationary stator which creates high levels of mechanical shear. Colloid mills work well with highly viscous materials such as toothpaste or peanut butter. Colloid mills are commonly found in the pharmaceutical, food, and chemical industries.

Vibratory Grinding Mill
Vibratory grinding mills are machines that use attrition, low energy impacts, and a grinding media to grind a feed material in a batch process or in a continuous flow process. First, material enters one end of a vibratory grinding mill drum into horizontal cylinders. Then, the mill uses a vibratory motion to mix and grind the particles between the mill media and the mill body. Vibratory grinding mills can operate in either wet or dry grinding processes.

Mix Muller
A mix muller is a machine designed for small to medium-sized difficult batch mixing applications. The mix muller consists of two muller wheels mounted against springs. As the feed material increases in volume and strength, the muller wheels rise and increase mulling pressure. This design provides the kneading and compression action of mulling that allows for a uniform mixture.

Attritor Mill
Attritor mills, also known as stirred ball mills, consist of a mixing vessel and a powered rotating mixing shaft with perpendicular arms. The design of the attritor shaft causes the media to exert both shearing and impact forces on the feed material resulting in an extremely fine product. These machines can operate wet or dry, introduce inert atmospheres, operate at controlled temperatures, and vary grinding speed. Attritor mills are a simple and effective method of grinding and dispersing fine and homogenous material quickly under various process conditions.

Jar Mill
Jar mills are machines designed to accommodate one or more grinding jars on two parallel rollers. The grinding jars rotate as the rollers rotate which provides a continuous grinding process inside the grinding jars. Jar mills work for wet or dry grinding, mixing and blending for a wide variety of materials like ores, chemicals, paints, ceramics, glass, and more.

Pellet Mill
Pellet mills, also known as pellet presses, are machines that are designed to create pellets from powdered material. Pellet mills are unlike grinding mills, in that they combine small materials into a larger, homogenous mass, rather than break large materials into smaller pieces. Pellet mills are commonly found throughout the chemical, plastics, ceramic, animal feed, and food and beverage industries.

Ball Mill
A ball mill is a type of tumbling mill that is designed to grind and blend bulk materials using different sized balls as grinding media. A ball mill consists of a rotating hollow drum closed with loading and unloading end caps. The drum is filled with grinding media and rotated around its axis. As the ball mill rotates, the grinding media bounces around striking the enclosed feed material. The force of this repeated contact results in a finer, less-coarse product medium. Ball mills are commonly used in the metallurgy, refractory, power, mineral processing, silicate, and chemical industries.

Conical Screen Mill
A conical screen mill, also called a conical mill, is a machine designed to reduce the size of a feed material in a uniform manner. Conical screen mills are often used in processes as alternatives to hammer mills or other grinding mills. Once material is fed into the mill by gravity or vacuum, a rotating impeller forces the material outward to a conical screen surface where it is sifted. Once completed, the product drops through the milling chamber and out the discharge. Conical screen mills are commonly found throughout the food, cosmetic, chemical, and pharmaceutical industries.

Disk Refiner
Disk refiners are machines designed to refine paper pulp. They consist of two vertical disks with serrated or otherwise contoured surfaces that rotate in different directions. The fiber slurry is pumped between the disks and centrifugal force pushes the pulp fibers out towards the perimeter of the disk. The abrasion cuts, softens, rubs, and disperses the fibers to the desired degree.

Jet Mill
Jet mills are milling machines designed to output a product with a narrow size distribution among the particles. The raw feed to a jet mill is usually the product of a mechanical mill like a hammer mill or roller mill. Jet mills are typically used to grind a dry powder to a range of 0.5 to 45 microns. Compressed gas is forced into the mill through nozzles tangent to the cylinder wall which creates a vortex. The gas leaves the mill through a tube along the axis of the cylinder. These mills are used to manipulate material for improved reaction rates, improved suspension of specialty chemicals, improved color characteristic for pigments, and improved strength qualities of products.

Lump Breaker
Lump breaker, also called lump crushers or flake breakers, are particle size reduction machines. The agglomerated feed material enters at the top of the unit. As the agglomerates pass through rotating blades and a set of stationary comb-like blades, the lumps are broken apart. The agglomerated particles continue to be reduced in size until they are small enough to pass through and discharge from the bottom. Lump breakers are common material handling machines used for materials like sugar, salt, resins, pigments, minerals, and more.

Pin Mill
Pin mills are machines that are designed to reduce particle size by the action of pins that repeatedly move past each other. These machines are a type of vertical shaft impactor mills and consist of two rotating disks with pins embedded on one face. The disks are positioned parallel to each other so that the pins of one disk face the pins on the other. The feed material is introduced into the space between the disks, and the disks then rotate at high speeds. As the disks rotate, the pins repeatedly strike the feed material and breaks down the size of solid particles. Pin mills can be used on both dry substances and liquid suspensions. Pin mills are commonly found throughout the pharmaceutical, chemical, and food processing industries.

2 Roll Mill
Two roll mills consist of two parallel horizontally mounted rolls of equal or near-equal size. These rolls are oriented side-by-side and rotate in opposite directions of each other at varying speeds. Feed material is introduced between the rolls in the form of lumps, pellets, chunks, or powder. As a result of rotation, adhesion, and friction, the material is entrained into the gap between the rolls. As the rolls rotate, they crush and mix the feed material. These mills can be used to mill solids in suspensions, pastes or ointments, grains, and more.

3 Roll Mill
Three roll mills, also called triple roll mills, are machines that use shear force created by three horizontally positioned rolls rotating in opposite directions and different speeds, in order to mix, refine, disperse, or homogenize a feed material. Three roll mills are commonly used to mix printing inks, high performance ceramics, cosmetics, pastisols, carbon/graphite, paints, pharmaceuticals, chemicals, glass coatings, adhesives, foods, and more.

4 Roll Mill
Four roll mills, also called four high rolling mills, consist of two sets of vertically stacked rollers. The feed material enters the mill where it goes through the first set of rollers which have a rather wide gap. The feed material is passed through the first set where it is reduced in size for the first time. After that, the feed material passes through the second set of rollers which further crushes the material and discharges a final product. Four roll mills can be used to mill a variety of materials from grain to metals.

Knife Mill
A knife mill is a machine designed for reducing particle of a material by shearing action that is provided by several sharp knives attached to an impeller. Knife mills are used on materials that can’t be crushed or compressed. Additionally, knife mills are used on materials that must be reduced to specific particle dimensions. As the feed material enters the knife mill and is reduced in size, it is sifted to a collection bin until the rest of the material has been fully reduced.

Mikro Pulverizer Hammer & Screen Mill
Mikro Pulverizer hammer & screen mills are pulverizer machines that consist of a high speed rotor assembly fitted with hammers. The grinding chamber is fitted with a cover containing a multiple deflector liner and a retaining screen at the point of mill discharge. A screw mechanism is often used to introduce feed material into the grinding chamber. The grinding process is affected by three basic variables: the type of hammers, the rotor speed, and the size and shape of the screen opening. Mikro Pulverizer hammer & screen mills grind, blend, and disperse in a single operation.

Mikro Atomizer Air Classifying Mill
Mikro Atomizer air classifying mills are machines that use airflow to convey materials to the grinding zone. Size reduction occurs when hammers fitted to the rotor impact particles at 4,000 to 8,000 RPM’s. A deflective liner returns oversized particles to the hammer impact zone for further reduction. The ground materials are then conveyed to the classifier wheels which are mounted to the grinding rotor. Larger particles are rejected for re-grinding as the desired particles are air conveyed by internal fan blades and exit the mill for collection.