Crushers are equipment for applying mechanical impact on hard materials for the purpose of their destruction. Other name of the crushers is stone-breakers or stone-crushers.
Our company produces a number of types of the crushers and in cooperation with our partners we deliver other types of the crushers that we do not produce.
Our equipment can use both hard and soft rocks as raw material. Different rocks have their own characteristics, so we use different stone-breakers to disintegrate them.
In some cases one type of the crusher will be enough, in other cases it will be necessary to install more complicated crushing-and- sorting lines.
The necessary type of crusher(s) depends on:
- the size of the particles we intend to obtain;
- the strength of the source material;
- the productivity of the machine;
Crushers are destined for disintegration of the material and for breaking it into smaller pieces. Depending on the size of the output material, crushers can be divided into fine crushing, medium crushing and coarse breaking units.
|Crusher type||Source material size|
(Input particles size), mm
|Final material size|
(Output particles size), mm
|Coarse breaking unit||600—1000||100—300|
|Medium crushing unit||100—300||25-100|
|Fine crushing unit||50-100||1-25|
Classification of Crushers by Their Action
There are various designs of crushers that employ different modes of crushing:
- cutting or loosening,
- shock impact (hammers, beaters, bumper plates),
- shock impact (free stroke, stone-on- stone stroke).
Classification of Crushers by Their Construction
According to their construction, crushers can be divided into the following groups:
- Jaw crusher
- Cone crusher
- Hammer crusher
- Roll crusher
- Disk (knife) crusher
Mills can be marked out separately. The most popular types of mills are:
- Ball mill
- Vibratory mill
Depending on the Installation Method, Crushers Can Be Divided into the
- Stationary crushers
- Mobile crushers on wheeled or caterpillar chassis
Operation Particularities Depending on the Execution
Stationary execution of crusher usually requires approved technical documents, construction operations of different complexity level (laying the foundations etc.) and erection of the appropriate infrastructure. Construction work and equipment (crushers) assembling usually take 2 or 3 months.
Mobile crusher is a self-propelled device within a quarry but requires a specially organized transportation from one site to another over the roads of general use. The advantages of a mobile crusher:
- as a rule, no approved project is required for putting in operation;
- as a rule, foundation is not required for putting in operation (construction work is reduced to minimum or is not required at all);
- deployment into ready-to- work position takes minimum of the time – 4 to 16 hours as usual;
- mobile crusher ensures free transportation over the quarry to the site of the rock removal, to eliminate primary transportation of raw materials.
There are stationary crushers very light in weight that can be installed without special foundations, what saves time for dismantling and assemblage at the new site.
Use of Crushers for Additional Crushing of Screenings (Stone Breaking Waste Products)
Our equipment uses rock screenings as raw material very often. Rock screenings are stone breaking waste products. The point is the 0—10 mm (or 0—5 mm) fraction meets very little use and therefore becomes accumulated in waste piles in very large quantities. Such fraction is an excellent raw material for our presses (and other equipment) but it requires additional crushing, usually up to the fraction of 0—3 mm.
For crushing of such raw material up to the fraction of 0—2 (0—3) mm, some types of crushers can be successfully used:
- Roll crusher
- Hammer crusher
The roll crusher is more preferable to this end because of the lesser maintenance work. Rolls made of high-quality steel guarantee the reliability of the crusher without maintenance over the time of 12 months or more.
The hammer crusher is very simple and cheap but it requires rather frequent replacement of hammers (steel plates). For example, even when crushing lime it is required to replace hammer kit every 2 or 3 weeks.
Both of the crushers are sensitive to the excessive humidity of raw material.
Use of Crushers for Operation Directly in Quarries
To obtain the determined fractions it is necessary to disintegrate the material, usually by means of a number of crushers. For example, primary crushing requires one type of crushers (e. g. jaw crusher); for obtaining the medium size particles, the other type of crushers is used (e. g. impact crusher); and to obtain the small fraction fines, a third type (hammer, roll etc.) is necessary. Each crusher is designed for the certain size of the particles at the input and usually conveys the processed particles to the riddle (sieve). For production of powders (when the material undergoes further disintegration), mills are used. In cases when the size of the stones is too big even for the first stage, special stone-cleavers find their application.
Crushers are employed for production of smaller raw material fraction which can be used toward different ends or undergo additional crushing with mills.
In the course of operation, excavators, front-end loaders and tipper trucks deliver the raw material of different sizes into the feeder which passes the raw material into primary classifier (sieve) for selection of particles which do not require crushing.
Vibratory sieve (bolter, sifter, screen, separator or riddle) is a sifting device used in various branches of industry (mining, food manufacturing etc.).
Rotating barrel (drum) is capable to do uniform sifting of the most complicated materials, using the feed motion mechanism with automated load control in the best way. Rotating screen has a large sifting surface that allows to increase the productivity of the sifting.