Today in the construction industry it is difficult to find such a popular material as crushed stone. It is used in the construction of road surfaces and landscaping as a filler in concrete solutions. The quality of such crushed stone is determined by its origin, material characteristics and fraction size. It should be said that it is often difficult to obtain crushed stone of the same shape and size. It is necessary to use special crushers for grinding, which are manufactured in a wide range.
Such equipment for crushing crushed stone is usually divided according to the resulting stone fraction size. There are three categories of equipment based on stone size:
- 5-25 millimeters.
- 25-100 millimeters.
- 100-300 millimeters.
It should be noted that today, installations that make it possible to produce crushed stone of various classes are very popular, for which it is only necessary to reconfigure the equipment. It is also customary to distinguish between mobile and stationary models. It should be noted that stationary crushers are used mainly in large enterprises and are characterized by increased power. Mobile units have low productivity, but due to their compact dimensions they can be easily transported from one construction site to another. Mobile types of crushers use a screw or cone type. It must be said that in recent years, universal equipment has appeared that allows you to work with crushed stone from various materials, obtaining stones of both small and large fractions.
Types of crushing complexes
Almost all crushed stone used in road construction is obtained by crushing rocks using specialized equipment, united by a single concept - crushers. This single name refers to machines whose operating principles are essentially different. The only thing that unites them is their functional purpose - to turn a fragment of quarry stone into a product useful for construction.
There are three basic types of crushers, and these differences are based on three types of impact of the working crushing body on the material being processed.
The jaw crusher, which appeared first in chronology, uses the effect of crushing material between two surfaces with a relatively slow increase in pressure. The cone crusher uses both abrasion and compression of material between two moving surfaces. An impact crusher (and primarily a rotary crusher, which appeared in the mid-twentieth century) crushes material by impact: either on a piece of material lying on the surface, or by hitting a fast moving part (up to 70 m/sec.) on a piece of material, or by hitting a piece material moving at high speed against a stationary plate.
Since the previous issue of our directory for 2002 included a detailed article on cone crushers, the authors will focus their attention on jaw and rotary machines, which together provide about 80% of the world's total crushed stone production.
The main parameters characterizing a jaw crusher are the maximum dimensions of the loading and discharge openings. The width of the loading opening determines the largest size of loaded pieces of material. The size of the maximum piece is taken to be 0.8–0.85 of the width of the loading opening. The productivity of the crusher depends on the uniformity of the supply of material and the uniformity of its distribution along the length of the loading opening.
All productivity values indicated by manufacturers in advertising catalogs are for reference only, theoretically calculated based on the maximum capabilities of the machine when crushing a reference material of a certain initial size and strength. Since the value of real productivity is influenced by the method and intensity of supply of the source material, the heterogeneity of its granulometric composition with the possibility of “oversize” or uncrushed elements entering, the real value of productivity should be estimated as 60–75% of those indicated in advertising catalogs.
Rice. 1. Jaw crusher with complex jaw swing
All existing types of jaw crushers are divided according to the nature of the movement of the movable jaw into two large classes - crushers with simple or complex swing (Fig. 1). Crushers with complex jaw swing ensure crushing of the material not only due to compression, but also due to its abrasion between the compressing surfaces, since the magnitude of the vertical component of the jaw stroke in these crushers is significantly higher. However, the cost of this increased efficiency is a reduction in the service life of the protective linings due to increased wear of the lining material.
Based on their design characteristics, all existing impact crushers are divided into the following types: hammer crushers with hinged hammers and rotary crushers with rigidly fixed beaters.
For the production of marketable crushed stone from rocks, rotary crushers are mainly used, since the grates of hammer crushers do not allow reliable operation with material of medium and high strength.
Let's consider the real modern market of crushing equipment designed for high-performance production of commercial crushed stone.
R rs
Завод РџР РћРњРРљ для дробления RјРёРЅРµСЂР°Р»СЊРЅРѕРіРѕ SЃС‹СЂСЊСЏ второ Р№ Рё третьей стадий предлагает СЂРѕС‚ орные РґСЂРѕР±Релки последнего RїРѕРєРѕР»РµРЅРёСЏ, разработанны Рµ для стабРельной Рё высоконадеж РЅРѕР№ работы РІ сочетании СЃ простым техническим РѕР±СЃР»С ѓР¶РёРІР°РЅРёРµРј Рё возможностью Р± S‹СЃС‚СЂРѕР№ замены Резнашиваемых деталей. Роторные SѓРґР°СЂРЅС‹Рµ SЂРѕР±РёР»РєРё SЏРІР»СЏСЋС‚СЃСЏ SЃР°РјС‹РјРё востреб ованными РёР· дробилок разных S‚РёРїРѕРІ , имеющихся SЃРµРіРѕРґРЅСЏ РІ продаже.
R rs
Роторная дробилка для РєСѓР±РѕРІРёРґРЅРѕРіРѕ S‰РµР±РЅСЏ РїСЂРёРјРµРЅСЏРµС‚С ЃСЏ РІ РіРѕСЂРЅРѕ-металлургической, РіРѕСЂРЅРѕ-С…Ремической промышленности, РІ дорожном строительстве, РІ цементном керамическом RїСЂРѕРёР·РІРѕРґСЃС‚РІРµ.
RS‚Рѕ оборудование SЏРІР»СЏРµС‚СЃСЏ незаменимым для РїСЂРѕРёР·РІРѕР ґСЃС‚РІР° РєСѓР±РѕРІРёРґРЅРѕРіРѕ S‰РµР±РЅСЏ.
R”SЂРѕР±Р”ение S‰РµР±РЅСЏ SЃ S‚очки R·СЂРµРЅРёСЏ RµРіРѕ RєР°С‡РµСЃС‚РІР° оценив ается Рё такими РїРѕРєР°Р·Р°С ‚елями, как форма продукта Рё уровень лещадРхости (СЃРѕ держание зерен пластРенчатой Рё игловатой форм, снижающих качество RїСЂРѕРґСѓРєС‚Р° РґСЂРѕР± ления).
Материал, измельченный установкой этого типа, РёРјРµРµС ‚ большую прочность, С‡ ем обработанннй РЅР° РґСЂСѓРіРѕРј RѕР±РѕСЂСѓРґРѕРІР°РЅРЅРёРё: дробление РїС ЂРѕРёСЃС…РѕРґРёС‚ RїРѕ RјРёРєСЂРѕС‚рещинам РїРѕ лмниям RІРЅСѓС‚ренних нарушений структуры камня.
Кубовидность РґСЂРѕ±Р»РµРЅРѕРіРѕ RјР°С‚ериала – это условное РЅР °Р·РІР°РЅРёРµ формы зерен, напоминающих гексаэдр (шестигранник) Рё усеченный тетраэдр (С‡РµС ‚ырехгранник).
Кубовидный щебень имеет СЂСЏРґ качественных характеристРеРє:
- РїСЂРё его пспользованнии существенно RїРѕРІС‹С€Р°РµС‚СЃСЏ РїСЂРѕ S‡РЅРѕСЃС‚СЊ SЃС‚роительного RѕР±СЉРµРєС‚Р° или RґРѕСЂРѕР¶РЅРѕРіРѕ RїРѕР»РѕС ‚PSP°;
- значительно СЃРЅРѕ¶Р°РµС‚СЃСЏ расход битума, цемента Рё СЃРѕ±С ЃС‚венно щебРСЏ;
- RІРґРІРѕРµ SЃРЅРёР¶Р°РµС‚СЃСЏ время, необходимое РЅР° SѓРєР»Р°РґРєСѓ асфал ьта, РїСЂРё повышении коэффициентР° сцепления РґРѕ 0.65-0.7.
Купить роторную дробилку: цена, запчасти
Особенностью СОксплуатации SЂРѕС‚РѕСЂРЅРѕР№ дробилки, РїСЂРёР јРµРЅСЏРµРјРѕР№ РЅР° второй стадии дробления для измельчення щебня крупных фракций, является повышенРSый РёР·РЅРѕСЃ Р±РёР», броневых РїР »РёС‚ Рё накладок РїСЂРё дроблении высокоабразивных материалов (более 90 РјРі).
RS‚Рѕ S…арактерно для всех РґСЂРѕР±Релок SЌS‚РѕРіРѕ S‚РеРїР°, незаввиси РјРѕ РѕС‚ места изготовления Рё С „РёСЂРјС‹-производителя. RР·РЅРѕСЃ Р±РёР» RјРѕР¶РЅРѕ RјРёРЅРёРјРёР·РёСЂРѕРІР°С‚СЊ R·Р° счет RѕRїS‚имизации СЂР µР¶РёРјРѕРІ дробления. Рђ также, РїСЂРё желании заказчика, – Р·Р° счет использования Р±Рё R" Рё ударных плит РёР· высокотехнологичной шведской ста R»Ryo Hardox.
Завод РџР РћРњРРљ предлагает роторные РґСЂРѕ±РёР»РєРё SЃРµСЂРёРё PCS-IC, Р±РёР »Р° Рё РґСЂСѓРіРёРµ запасные S‡Р °СЃС‚Рё как для дробилок RїРѕРґ SЃРІРѕРµР№ торговой маркой, так Рё R ґР»СЏ роторных дробилок РЎРњР» Рё RІСЃРµРіРѕ SЃРїРµРєС‚СЂР° дробильно-сортоЂРѕРІРѕС‡РЅРѕРіРѕ RѕР±РѕСЂСѓРґРѕ вания. РљСЂРѕРјРµ S‚РѕРіРѕ, РІ продаже – роторные дробилки РЎРњР»-75 после капремонта. R—воните!
Source: https://npo-promek.ru/catalog/rotornya-drobilka/
Drobmash
It is appropriate to start with the basic domestic manufacturer of crushers - OJSC Drobmash. Celebrating its 70th anniversary in 2003, this enterprise has practically emerged from the crisis situation of the mid-90s and is currently the main supplier of crushing equipment for the construction industry and related industries. The plant produces all known types of stationary equipment for producing marketable crushed stone.
First of all, an advantageous feature of current production compared to Western competitors is the availability of high-quality steels for the abraded surfaces of crushers - linings, beaters, hammers, etc. These steels, as before, are produced with a manganese content, which provides exceptional resistance to abrasion during crushing. Due to a number of environmental regulations affecting the economies of European Union countries, the production of manganese steels has been prohibited on its territory since the mid-90s. Thus, European manufacturers were forced to switch to the use of vanadium alloys, which have worse wear characteristics, when producing crushing elements.
OJSC "Drobmash" produces complete crushing equipment, both jaw and rotary.
The cheek group is represented by a range of standard sizes, consisting of 8 models, made according to a scheme with a complex swing of the cheek. These crushers ensure successful processing of material with a compressive strength of up to 300 MPa. The crushers have proven themselves to be reliable machines that crush rocks up to 600 mm in size ( DRO-609 ). The cost policy of the enterprise ensures stable demand for these machines. So, in mid-2002, the SMD-110A , cost about 60 thousand. e.
However, like all jaw crushers, their degree of material crushing is not high - see the graph of the granulometric composition of the finished material (Fig. 2).
Rice. 2. Graph of the granulometric composition of the finished material after crushing in a jaw crusher
Rice. 3. Graph of the granulometric composition of the finished material after crushing in a rotary crusher
The clear advantage of rotary crushers in terms of the degree of grinding is revealed when comparing the previous graph with Fig. 3, a graph of the grain composition of the crushing product of rotary crushers. The speed was up to 41.5 m/sec. allows for a degree of grinding of up to 7–8 units when crushing durable limestone. Such energy efficiency, of course, also has its downside - the production of an excessive amount of screenings (0-5 mm). However, this is compensated by the high yield of cube-shaped grains, which ensure high consumer qualities of commercial crushed stone.
The company produces four standard sizes of rotary crushers designed for coarse, medium and fine crushing of limestone, dolomite, marl, marble, gypsum, low-abrasive ores and other similar materials. The crushers are equipped with a safety and adjustment device that allows the passage of uncrushable bodies (an excavator tooth, for example) that fall into the crushing chamber, and the adjustment of the gap between the ends of the rotor beaters and the impact plates.
The required size of the crushed product is achieved by changing the rotor speed (by installing replaceable belt pulleys).
Rice. 4. Technological installation for processing construction waste
The company also produces the fifth model of an impact crusher - DRO-629 - a specialized granulator for producing crushed stone with a compressive strength of up to 200 MPa. It is intended exclusively for producing cube-shaped crushed stone.
Based on the above basic crushers, the company has created various technological schemes for obtaining various commercial products. Along with well-known schemes for producing crushed stone, there are two original installations designed for highly specialized materials.
In Fig. Figure 4 shows a technological installation for processing construction waste into marketable crushed stone. This two-stage, closed-cycle scheme was first implemented in 1996 on the territory of the Ochakovsky brick factory (Moscow).
Rotary machines were used as crushers - primary crushing - SMD-86A and secondary crushing - SMD-75A . This set of equipment has proven to perform almost flawlessly when processing such heterogeneous and heavy material as contaminated and littered construction scrap.
The only bottleneck of the entire complex was a vibrating feeder with a tray width of 320 mm, installed in the technological chain after the SMD-86A crusher. It quickly became clogged with wet debris. After replacing it with a standard apron feeder, the complex provided the required performance, provided that the source material was well prepared.
The second highly specialized machine, intended only for producing cube-shaped material, should be recognized as a separate installation - a granulator. This retrofitted impact crusher fits into any existing production line and is designed to increase the percentage of cubic grains.
The design of the granulator is similar to the impact crusher, however, it has the following significant differences.
- The volume of the crushing chamber has been significantly increased by reducing the number of impact plates to one. This achieves a reduction in the number of mutual collisions between pieces of material.
- The linear speed of the top point of the blows is reduced to 20 m/sec, which helps to reduce the number of crushing blows and their strength.
These design changes made it possible to turn the crushing machine into a granulating machine that determines the shape of the grains. It should be noted that this effect is achieved only with fine crushing, that is, at the final stage of producing fractional crushed stone. In practice, only flaky grains are crushed in the granulator, and grains that have already acquired cuboid shapes do not undergo shape-building changes. The idea of this machine stems from the theory of “minimum possible crushed grain”, substantiated by the late professor, Doctor of Technical Sciences. V. A. Bauman - former director of VNIIstroydormash.
Crushed stone crushers: impact crusher – main in cubic shape
When constructing highways, an important criterion that determines the reliability of their operation is the quality of crushed stone used in the structural layers of the road pavement. Every year, road workers need tens of millions of cubic meters of cube-shaped crushed stone to fill the top layer of roads.
Impact, abrasion and crush crushers
Almost all crushed stone used in road construction is obtained by crushing rocks using specialized equipment with a single name - crushers, which combines machines whose operating principles are essentially different. The only thing they have in common is their functional purpose - to turn quarry stone into a product useful for construction.
There are three basic types of crushers - according to three types of impact of the working crushing body on the processed material.
The jaw crusher, which appeared first, uses the effect of crushing material between two surfaces with a relatively slow increase in pressure. The operating principle of a cone crusher is based on both abrasion and compression of material between two moving surfaces. An impact crusher (and primarily an impact crusher, which appeared in the mid-twentieth century) crushes material through impacts: either on a piece of material lying on the surface, or by hitting a fast moving part (up to 70 m/sec.) on a piece of material, or by hitting a piece of material moving at high speed against a stationary plate. Jaw and impact crushers today account for about 80% of the world's total crushed stone production.
The main parameters characterizing a jaw crusher are the dimensions of the loading and discharge openings . The width of the loading opening determines the largest size of loaded pieces of material. The maximum size of the loaded piece is taken to be 0.8–0.85 of the width of the loading opening. The productivity of the crusher depends on the uniformity of the supply of material and the uniformity of its distribution along the length of the loading hole .
All productivity values indicated by manufacturers are for reference only, theoretically calculated based on the maximum capabilities of the machine when crushing a reference material of a certain initial size and strength. Since the value of real productivity is influenced by the method and intensity of supply of the source material, the heterogeneity of its granulometric composition with the possibility of “oversize” or uncrushed elements entering, the real value of productivity should be estimated as 60–75% of those indicated in advertising catalogs.
Jaw crushers, based on the nature of the movement of the movable jaw, are divided into two large classes - crushers with simple or complex swing of the jaw. Crushers with complex jaw swing ensure crushing of material not only due to compression, but also due to its abrasion between the working surfaces, since the magnitude of the vertical component of the jaw stroke in these crushers is significantly higher. However, the cost of this increased efficiency is a reduction in the life of the protective linings due to increased wear.
Based on their design characteristics, all existing impact crushers (impact crushers) are divided into the following types: a hammer crusher with hinged hammers and an impact crusher with rigidly fixed beaters.
For the production of marketable crushed stone from rocks, rotary crushing equipment is mainly used, since the grates of hammer crushers do not allow reliable operation with material of medium and high strength.
Icon of domestic crushing style
The basic domestic player in the market of crushing equipment intended for high-performance production of commercial crushed stone is considered to be Drobmash OJSC, which is now celebrating its 80th anniversary and produces all known types of stationary equipment for producing commercial crushed stone.
The jaw group is represented by a standard-size range of crushers made according to a scheme with a complex jaw swing, which ensure successful work with material with a compressive strength of up to 300 MPa. The crushers have proven themselves to be reliable machines that provide crushing of rock with a piece size of up to 600 mm (DRO-609). The cost policy of the enterprise ensures stable demand for these machines.
However, like all jaw crushers, their degree of material reduction is not high. The rotary machine has a clear advantage in terms of the degree of grinding. (See graphs of the granulometric composition of the finished material.)
Graph of the granulometric composition of the finished material after crushing in a jaw crusher
Graph of the granulometric composition of the finished material after crushing in a rotary crusher
The beat speed of up to 41.5 m/sec allows for a degree of grinding of up to 7–8 units when crushing durable limestone. This energy efficiency also has its downside - the production of a large number of screenings (0–5 mm). However, this is compensated by the high yield of cubic grains, which ensure high consumer qualities of crushed stone.
The company produces several standard sizes of rotary equipment designed for coarse, medium and fine crushing of limestone, dolomite, marl, marble, gypsum, low-abrasive ores and other materials with similar characteristics. The crushers are equipped with a safety and adjustment device that allows the passage of uncrushable bodies (an excavator tooth, for example) that fall into the crushing chamber, and the adjustment of the gap between the ends of the rotor beaters and the impact plates. The required size of the crushed product is achieved by changing the rotor speed (by installing replaceable belt pulleys).
Based on the above basic crushers, the company has created various technological schemes for obtaining various commercial products. Along with well-known schemes for producing crushed stone, there are two original installations designed for highly specialized materials. Firstly, this is an installation for processing construction waste into marketable crushed stone. This two-stage, closed-cycle scheme was first implemented in 1996 on the territory of the Ochakovsky brick factory (Moscow). Rotary machines were used as crushers - primary crushing - SMD-86A and secondary crushing - SMD-75A. This set of equipment has proven to perform almost flawlessly when processing such heterogeneous and heavy material as contaminated and littered construction scrap. The only bottleneck of the entire complex was a vibrating feeder with a tray width of 320 mm, installed in the technological chain after the SMD-86A crusher. It quickly became clogged with wet debris. After replacing it with a standard apron feeder, the complex provided the required performance, provided that the source material was well prepared.
The second highly specialized machine, designed only for producing cube-shaped material, should be called a separate installation - a granulator. This retrofitted rotary machine fits into any existing production line and is designed to increase the percentage of cube grains.
The design of the granulator is similar to the impact crusher, however, it has the following significant differences:
- The volume of the crushing chamber has been significantly increased by reducing the number of impact plates to one. This achieves a reduction in the number of mutual collisions between pieces of material.
- The linear speed of the top point of the blows is reduced to 20 m/sec, which helps to reduce the number of crushing blows and their strength.
These design changes made it possible to turn the crushing machine into a granulating machine that determines the shape of the grains. It should be noted that this effect is achieved only with fine crushing, that is, at the final stage of producing fractional crushed stone. In practice, only flakier grains are crushed in the granulator, and grains that have already acquired cuboid shapes do not undergo changes. The idea of this machine stems from the theory of “minimum possible crushed grain”, substantiated by Professor, Doctor of Technical Sciences. V. A. Bauman, former director of VNIIstroydormash, now deceased.
At the beginning of the century, another manufacturer of crushing and grinding equipment appeared in Russia - New Technologies CJSC (St. Petersburg). The equipment produced by the company is based on long-standing developments of the Ministry of Medium Machine Building of the former USSR. In a short period of time, the company has mastered a large standard range of rotary inertial crushers with a vertical rotor arrangement, with a productivity of 1 to 650 tons per hour. The design of the crushers is based on the “stone on stone” crushing principle, well known since the beginning of the last century, which is widely used by such well-known manufacturers as Nordberg (Barmac), Koldberg-Pioneer, etc.
However, there are also significant differences in the design, which include, first of all, the use of so-called air-static support instead of complex and not very reliable bearing systems. In this case, rotation is transmitted to the working element through the cardan shaft, and the air cushion created in the support makes it possible to reduce by an order of magnitude the influence of unbalance that occurs when crushing materials. All this made it possible to significantly increase not only the reliability and durability of the equipment, but also the size of the initial feed, as well as the impact speed.
Crushing at higher speeds (for crushed stone the speed is 56–64 m/sec) allows you to increase not only the degree of crushing, but also the quality of the resulting crushed stone. Thus, when crushing granites, the cubic shape is 93–98%, and when processing materials with a slate-like structure (helleflints, basalts) – 89–93%. Moreover, the shape of the grain is preserved in all fractions, including small ones, which allows the screenings to be used as artificial sand.
Note from the site editor:
This text is based on articles in a reference book written more than ten years ago. Today it is impossible to quote without comment, for example, the following: “Currently, about 15 imported crushed stone production lines operate in our country...”
We undertook this publication, on the one hand, with the aim of giving a systematic idea of the types of crushing units, which can only be obtained in scientific publications that are not intended to correspond to market trends. On the other hand, out of respect for manuscripts that “do not burn,” even if there are no longer 15, but 1,115 “imported crushed stone production lines operating in our country.” For this reason, let us make a reservation: subsequent references to foreign manufacturers are not of an evaluative nature, do not pretend to be comprehensive, and only indicate who was the leader in the world of crushing equipment a couple of decades ago.
Japanese crushing
Nakayama , an established global manufacturer of mining equipment, offers commercial crushed stone producers a comprehensive range of jaw crushers, from heavy-duty quarry coarse crushers weighing over 100 tons to fine crushers weighing around two tons. Six series of jaw crushers: RJ, RS, SK, HS, HF and AC - provide a wide choice for consumers interested in a variety of crushing machines, in terms of both productivity and the size and type of raw material processed. The manufacturer offers both well-known suspension and drive schemes for the movable cheek - with simple swing and with complex swing. However, a characteristic feature of machines of this brand is the presence of crushers with a low loading point. This makes it possible to reduce the dimensions of the entire crushing plant by significantly reducing the height and length of the feed conveyors.
An interesting engineering solution is an attempt to smooth out, perhaps, the only obvious drawback of jaw crushers - the high percentage of flake grains. For this purpose, in the HS series models, the peripheral speed of the drive shaft is increased by a quarter, compared to a conventional crusher, while simultaneously reducing the length of the crushing plate, and therefore the number of compressions of the material by the crushing plates.
This design, approaching the impact of rotary equipment in its effect on the material, certainly increases the percentage of cube-shaped material. The crusher is installed in the technological scheme as a secondary crushing unit that controls the quality of the finished product.
The company also produces a range of standard sizes of rotary machines. The range of installed power from 22 to 250 kW provides productivity from 20 tons per hour (for the NCF-1A ) to 360 tons per hour (for the NCF-3D ).
The design is equipped with three fender plates, two of which are adjustable with screw rods. The working part of the crusher, the rotor, has four rows of impact blows. The maximum linear speed of the top point of the blow does not exceed 30 m/sec.
The productivity of the crusher depends on the duration of the operating cycle. To reduce the loss of working time caused by the need to regularly change or rearrange the beaters, the opening of the housing is made as easy as possible, and the housing elements are equipped with hydraulic power cylinders that ensure quick and easy opening and closing of the housing cover.
The crushers listed above are the basic elements of crushing and screening complexes designed for the production of crushed stone from natural rock mass. Such installations are used as primary ones, both jaw and rotary models.
The diversified concern Komatsu is represented by a standard range of mobile tracked machines, five of which are equipped with jaw crushers, and two with rotary crushers. Rotary crushing equipment is focused on medium crushing (max. piece size is 500x500x200), and jaw crushers can accept pieces with a maximum size of up to 1200 mm. The bunker facility is equipped with both vibrating and apron feeders. The units are equipped with Komatsu engines with direct fuel injection and turbocharging, allowing them to reach travel speeds of up to 3 km per hour.
Jaw crusher that operates lying down
The 200-year-old mining company Westfalia and Braun has achieved a leading position in its field thanks to its impact roll crusher . Along with this outstanding design, the company produces three types of impact crushers and one type of jaw crusher.
The rotary machine is equipped with two hydraulically adjustable impact plates and a rotor with four rows of impact bars. The tracking system for adjusting the crusher outlet slot ensures smooth installation of the impact plates during operation, which maintains a constant and optimal particle size distribution of the product, avoids costly downtime and reduces blower wear to a minimum.
If a material blockage occurs at the crusher inlet, the front crushing casing is lifted hydraulically and the blockage is thus cleared without much effort. In this case, the width of the loading hole does not change.
To facilitate maintenance work, the crusher body is opened using two hydraulic power cylinders.
The Westfalia and Braun jaw crusher is also completely unusual. Its design will be of interest to consumers who are limited in height when using crushing and screening equipment. The well-known jaw circuit in this design has undergone a number of modifications: the location of the crusher has been changed, it now “lies” on the side generatrices of the crushing jaws , and the material does not enter the crushing chamber due to gravity, but is fed there by a chain plate conveyor.
The undoubted achievement of this crusher is the low level of material loading - only 1 m above the ground . This simultaneously solves several perennial loading problems - the loader does not need to lift the bucket, thereby saving fuel, reducing the work cycle and increasing equipment productivity. This level of loading makes it possible to completely exclude the loader from the technological scheme - the material can be supplied directly from the body of the dump truck. The material, having entered the tray of the chain feeder, is pulled under the closing crushing jaws under the action of its creeping bars, where it is crushed.
The stumbling block for any stone crusher is the entry of either “oversize” or uncrushable material into the crushing chamber. In this design, this problem is successfully solved by including a processor in the electrical control circuit of the conveyor, which receives control signals from the conveyor chain tension sensor. If the material jams the conveyor chain, the sensor “informs” this to the processor, which first stops the conveyor and then turns it into reverse for about 1 m. After this, the conveyor re-feeds the material into the crushing chamber, and this continues until the material is conveyor will not be positioned correctly.
HARTL: Origins
Kleemann Reiner company, which is consistently advertised on the Russian market, produces complete crushing equipment. The company offers to the market 15 models of jaw crushers for medium and coarse crushing for materials with a compressive strength of up to 320 MPa and three models for fine crushing, designed for materials with a strength of up to 500 MPa. All models use a complex swing pattern of the movable cheek.
Along with this, the company produces its own rotary series , consisting of five standard sizes of medium and coarse crushers. The design differs from the known ones in the increased volume of the working chamber, which makes it possible to increase the percentage of cube-shaped grains. Two impact plates are located almost vertically, thereby reducing the number of collisions of crushed material in the chamber. The impact crusher has a capacity from 170 to 900 t/hour.
The undisputed leader in the European heavy equipment market, KRUPP FORDERTECHNIK is represented by a comprehensive line of jaw and impact crushers, made according to classical designs. Almost all medium crushers have three designs - stationary, semi-mobile and mobile .
It is necessary to pay attention to the Austrian crushing complex STARTRACK-404 PCVG operated in Moscow by HARTL . Its functional purpose is more complex than crushing a homogeneous rock mass: it processes waste from the demolition of reinforced concrete and brick buildings. A rotor design with a rotor diameter of 1250 mm was chosen as a crusher. The operating weight of the installation is 42 tons, it is capable of processing construction scrap up to 700 mm in size with a rated capacity of 350 tons per hour. A receiving hopper with a capacity of 8 cubic meters, a vibrating feeder that is stepwise adjustable in transportation speed, a preliminary (before the crusher) vibrating screen that sifts out the fine fraction, rotary crushing equipment, a diesel generator with a hydraulic control system for actuators, an unloading conveyor, a magnetic separator, control station.
The crusher drive is a V-belt drive directly from the diesel engine. All other mechanisms, including tracked movers, receive torque from adjustable hydraulic motors of a single hydraulic system. The equipment set also includes a separate frame-mounted two-screen screen with three shipping conveyors, which are also driven by a single hydraulic system.
Despite all the undeniable progressiveness of the use of hydraulic systems, this design also revealed a real drawback in operating conditions in the cold season. Since the screen with conveyors is located at a significant distance from the central hydraulic system, its startup and operation at low temperatures (below - 10°C) is difficult.
HARTL produces two standard ranges of mobile crushers , one of which is equipped with jaw crushers, and the other with rotary crushers. Moreover, the rotary ones are equipped with two fender plates and a rotor with four rows of beaters. The company's designers pay special attention to the problem of increasing the efficiency of using expensive metal in working parts. There are four positioning options for the same beater. Two beaters are installed in one row (along the width of the rotor). After the start of operation, wear begins on the beaters in the central part of the rotor, and the beaters on the sides hardly wear out. Therefore, after the possibility of controlling the width of the discharge gap has been exhausted by changing the length of the fender plate rods, the two beaters are swapped, and their parts that have not yet been worn out end up in the center of the rotor. After abrasion of these parts, the beaters are turned over relative to their longitudinal axis. Since the bars of the beaters are made asymmetrical, this makes it possible to practically use the metal of the beaters by at least 38-40%.
Due to the geographical remoteness, crushing equipment made in the USA is little known in Russia. Perhaps only Eagle Crusher Сompany Inc. regularly reminds Russian consumers of itself at various construction forums. It is characteristic that the company practically switched to the production of exclusively semi-mobile plants, a priori expanding the field of action of such heavy equipment as stone crushing machines.
Equipped with an autonomous diesel drive, the rock crusher “lost” its previously inherent permanent residence in one quarry for its entire service life and turned into a highly mobile complex capable of crushing hard rocks at the place of their formation, changing location depending on the needs of crushed stone customers.
Rotary models are designed to handle the toughest materials, including reinforced concrete, dolomite, basalt, and mixed solid waste. The basic design is a rotary Jumbo 1400 with four rows of beaters on the rotor and three adjustable impact plates. The rotor has a mass of 11 tons and a width of 1450 mm. The weight of the entire crusher is close to 20 tons. The supply of source material is provided by a vibrating screen-feeder with dimensions of 5.49x1.45 m with a loading height of 4.72 m. A 175 kW generator provides energy to the installation and has reserve power for connecting an additional screen and a set of shipping conveyors. The maximum possible productivity of such a machine does not exceed 540 t/hour.
Other representatives of this series - Mighty Max, Jumbo 1000-15 UltraMax and Jumbo 1200-25 UltraMax - differ from the above only in smaller sizes and performance values.
Metso Minerals: a classic in the crushing genre
A wide selection of crushing and screening equipment is presented by the Scandinavian association Metso Minerals , which until recently operated on world markets under two independent leading mining brands Svedala and Nordberg . An analysis of crushing equipment produced by Metso Minerals makes us note its undeniable technical and technological advantages.
The non-welded modular frame design of the Nordberg C Series jaw crushers minimizes the presence of structural stress raisers, which has a beneficial effect on the overall reliability of the machine, which typically operates under variable loads. The excellent kinematics of the crusher, ensured by the optimal grip angle, the steep angle of the spacer plate, the non-flat, shaped profile of the outer edges of the crushing plates and the increased speed of rotation of the flywheel, make the Nordberg C Series jaw crusher more productive than other crushers of similar sizes.
The Nordberg C series crusher is very convenient to work with and maintain. Inspection points and lubrication points are kept to a minimum. The size of the unloading gap is adjusted steplessly using a wedge mechanism.
Two adjusting wedges located towards each other, with their relative displacement, set and maintain the position of the movable cheek. This adjustment is very quick and safe and can be done even without stopping the crusher. It is possible to use both manual and electro-hydraulic drives of the adjustment mechanism.
Unlike hammer crushers , in which crushing of crushed stone occurs by impacting the material on hammers and reflective plates, rotary inertial crushers Nordberg Barmac , produced by the Scandinavian engineering association Metso Minerals, have a number of undeniable technological and technical advantages for the production of small fractions of crushed stone with a cube-shaped grain from stone materials with a high degree of abrasiveness.
Metso Minerals, using a Nordberg Barmac rotary inertial crusher, offers in the most economical mode to obtain crushed stone of granite, gabbroic and other abrasive rocks with a cube shape of 85–95% for small fractions of 3–5 mm, 5–10 mm, 10–15 mm. This is achieved by using the “stone on stone” impact crushing principle discovered and perfected by Metso Minerals, that is, the impact crushing principle with minimal wear on the working elements of the machine. The fact is that the crushing chamber and the crusher rotor are lined directly with the processed material, and particles of the material are crushed by hitting each other, and not against the elements of the crusher.
One of the additional benefits of using a Nordberg Barmac crusher is the ability to produce cube-shaped material across the entire product range of 0-20 mm. That is, along with fractions 5–10, 10–15, 15–20 mm, it is possible to produce high-quality artificial granulated sand 0–5, which is successfully used at the asphalt plant as a filler.
The rotary Nordberg NP is also produced. When processing limestone and similar low-abrasive rocks, Nordberg TP Series crushers , thanks to a specially designed crushing chamber profile and an improved rotor design with increased inertia, have a high crushing ratio and are very efficient.
Nordberg NP can be used at the first, second and third stages of crushing, including in technologies for crushing construction waste. The presence of auxiliary hydraulic cylinders for adjusting the position of the deflector plates and lifting the upper part of the crusher body for maintenance makes this machine very convenient to use.
A specially designed system of one-sided wedge fixation of the hammers to the rotor ensures their tight contact and reduces the risk of breakage of these crusher components. The presence of a winch, included with the crusher and located on top of the crusher on a special rotating beam, makes the procedure for replacing the beater less labor-intensive.
The range of Nordberg C series jaw crushers, Barmak rotary inertial crushers and Nordberg NP hammer crushers is very wide. This equipment is offered for delivery in the form of self-propelled units on crawler tracks, mobile units on wheeled semi-trailers or on supporting metal structures.
The text was prepared based on the publication of V.Ya. Balagula and O.L. Sanko in the magazine "Road Equipment"
"New technologies"
Not long ago, another manufacturer of crushing and grinding equipment appeared in Russia - New Technologies CJSC (St. Petersburg). The equipment produced by the company is based on developments made twenty years ago by the Ministry of Medium Machine Building of the former USSR. In a short period of time, the company has mastered a large standard range of rotary inertial crushers with a vertical rotor arrangement, with a productivity from 1 to 650 tons/hour. The design of crushers is based on the principle of “stone-on-stone” crushing, well known since the beginning of the last century, which is now widely used by such well-known manufacturers as Nordberg (Barmac), Koldberg-Pioneer, etc.
However, there are also significant differences in the design, which include, first of all, the use of so-called air-static support instead of complex and not very reliable bearing systems. In this case, rotation is transmitted to the working element through the cardan shaft, and the air cushion created in the support makes it possible to reduce by an order of magnitude the influence of unbalance that occurs when crushing materials. All this made it possible to significantly increase not only the reliability and durability of the equipment, but also the size of the initial feed, as well as the impact speed.
Crushing at higher speeds (for crushed stone the speed is 56–64 m/sec.) allows you to increase not only the degree of crushing, but also the quality of the resulting crushed stone. Thus, when crushing granites, the cubic shape is 93–98%, and when processing materials with a slate-like structure (helleflints, basalts) – 89–93%. Moreover, the shape of the grain is preserved in all fractions, including small ones, which allows the screenings to be used as artificial sand.
Currently, about 15 imported crushed stone production lines operate in our country. Each of the crushers has its own niche of application and, as a rule, is selected for the specific operating conditions of the quarry.
Let's look at a number of the most modern models of crushers produced by the world's leading manufacturers in this area.
Japanese manufacturers are represented on the Russian market by well-known global manufacturers of heavy mining equipment - Nakayama and Komatsu.
Nakayama
Rice. 5. Jaw crusher (HS series model) can significantly reduce the percentage of flake grains
A generally recognized global manufacturer of mining equipment, it offers producers of commercial crushed stone a comprehensive range of jaw crushers.
From heavy quarry coarse crushers weighing over 100 tons to fine crushers weighing about 2 tons. Six standard size series - RJ, RS, SK, HS, HF and AC - jaw crushers provide a wide choice for consumers interested in various purposes of crushing machines, relating to both productivity and the size and type of raw material being processed. The manufacturer offers both well-known suspension and drive schemes for the movable cheek - with simple swing and with complex swing. However, a characteristic feature of machines of this brand is the presence of crushers with a low loading point. This makes it possible to reduce the dimensions of the entire crushing plant by significantly reducing the height and length of the feed conveyors.
An interesting engineering solution is an attempt to smooth out, perhaps, the only obvious drawback of jaw crushers - the high percentage of flake grains. HS series models (Fig. 5), compared to a conventional crusher, the peripheral speed of the drive shaft is increased by a quarter while simultaneously reducing the length of the crushing plate, and therefore the number of compressions of the material by the crushing plates.
This design, approaching in its impact on the material to impact rotary crushers, certainly increases the percentage of cube-shaped material. The crusher is installed in the technological scheme as a secondary crusher that controls the quality of the finished product.
Rice. 6. Jaw crusher (AC series model)
Depending on the type of material being processed, the AC (Fig. 6) is equipped with three types of crushing plates with different lining patterns. Using them in accordance with the source material increases the efficiency of pinching and crushing the latter.
This company also produces a standard range of impact crushers, consisting of nine units. The range of installation power, varying from 22 to 250 kW, provides productivity from 20 t/h (for the NCF-1A ) to 360 t/h for the NCF-3D .
The design is equipped with three fender plates, two of which are adjustable with screw rods. The working part of the crusher, the rotor, has four rows of impact blows. The maximum linear speed of the top point of the blow does not exceed 30 m/sec.
The productivity of the crusher depends on the duration of the operating cycle. To reduce the loss of working time caused by the need to regularly change or rearrange the beaters, the opening of the housing is made as easy as possible, and the housing elements are equipped with hydraulic power cylinders that ensure quick and easy opening and closing of the housing cover.
The crushers listed above are the basic elements of crushing and screening complexes designed for the production of crushed stone from natural rock mass. Such installations are used as primary ones, both jaw and rotary crushers (Fig. 8 and 9).
Rice. 8. Crushing and screening complex with jaw crusher | Rice. 9. Crushing and screening complex with impact crusher |
The specific choice of the type of equipment depends on the type of material being processed, its abrasiveness, the quality and purpose of the finished product, the required percentage of cube-shaped grains, the expected productivity, and the ability to bear the costs of restoring the functionality of the working parts.
How to choose the right crusher?
When choosing an impact crusher, you need to consider the following issues:
- What material will be crushed in the crusher.
- What are the dimensions of the loaded material.
- Unit performance.
- What size of crushed material will come out of the crusher.
- How will the crusher be loaded - manual or mechanized?
- How to unload material from a crusher - manually or using machinery.
First of all, you need to understand what material will be crushed. The type of crusher may depend on this.
Depending on the size of the loaded material, the type of crusher can be selected - rotary or shredder.
Depending on the required productivity, the power of the unit is selected; more powerful crushers are larger and more expensive. The productivity of the crusher is also affected by the size of the resulting fraction of crushed material. The smaller the calibrating grid cells, the lower the productivity of crushers of the same power.
When choosing the type of loading, you must keep in mind that for powerful, high-performance crushers, it is not easy to manually load large quantities of raw materials. In addition, when using a conveyor, you can use a metal detector to protect yourself from metal objects getting on the blades of the impact crusher.
For high-performance crushers, it is desirable to use conveyors or a pneumatic conveying channel.
Komatsu
The diversified concern Komatsu is represented by a standard range of seven mobile tracked machines, five of which are equipped with jaw crushers, and two with rotary crushers. Impact crushers are focused on medium crushing (max. piece size is 500x500x200), and jaw crushers can accept pieces up to 1200 mm long. The bunker facility is equipped with both vibrating and apron feeders. The units are equipped with Komatsu engines with direct fuel injection and turbocharging, allowing them to reach travel speeds of up to 3 km per hour.
Price
| Model | Type | Productivity, t/h | Max. loading size, mm | Price, thousand rubles |
| SMD-741 | Cheek | 23 – 53 | 900 | 1250 |
| KSD-600 | Conical | 19 – 40 | 90 | 550 |
| SMD-94B | Rotary | 210 | 600 | 3150 |
| DV-400Z | Valkovaya | 25 – 55 | 250 | 720 |
When purchasing equipment of this type, you should take into account its high cost. Moreover, such a high price is also observed for used rock crushing equipment. Only small crushers have an affordable price, but today they are not in sufficient demand among buyers.
Westfalia and Braun
Rice. 10. Impact crusher
A wide range of offers from German crusher suppliers. A mining company with a 200-year history, Westfalia and Braun has achieved a leading position in its field thanks to its impact roll crusher (see our 2001 guide). Along with this outstanding design, the company produces three types of impact crushers and one type of jaw crusher.
The impact crusher (Fig. 10) is equipped with two hydraulically adjustable impact plates and a rotor with four rows of impact beaters. The tracking system for adjusting the crusher outlet slot ensures smooth installation of the impact plates during operation, which maintains a constant and optimal particle size distribution of the product, avoids costly downtime and reduces blower wear to a minimum.
If a material blockage occurs at the crusher inlet, the front crushing casing is lifted hydraulically and the blockage is thus cleared without much effort. In this case, the width of the loading hole does not change.
To facilitate maintenance work, the crusher body is opened using two hydraulic power cylinders.
As a separate component, the crusher can be integrated into stationary and mobile installations.
Rice. 11. The crushed material is pulled by a chain plate conveyor to the working chamber of the jaw crusher
The Westfalia and Braun jaw crusher is also completely unusual Its design will be of interest to consumers who are limited in height when using crushing and screening equipment.
The well-known jaw circuit in this design has undergone a number of modifications: the location of the crusher has been changed, it now “lies” on the side generatrices of the crushing jaws, and the material enters the crushing chamber not due to gravity, but is fed there by a chain plate conveyor.
The undoubted achievement of this crusher (Fig. 11) is the low level of material loading - only 1 m above the ground. This simultaneously solves several common loading problems - the loader does not have to lift the bucket, thereby saving fuel, reducing cycle time and increasing equipment productivity. This level of loading makes it possible to completely exclude the loader from the technological scheme - the material can be supplied directly from the body of the dump truck.
The material, having entered the tray of the chain feeder, is pulled under the closing crushing jaws under the action of its creeping bars, where it is crushed.
The stumbling block of any crusher is the entry of either “oversized” or uncrushable material into the crushing chamber. In this design, this problem is successfully solved by including a processor in the electrical control circuit of the conveyor, which receives control signals from the conveyor chain tension sensor. If the material jams the conveyor chain, the sensor “informs” this to the processor, which first stops the conveyor and then turns it into reverse for about 1 m. After this, the conveyor re-feeds the material into the crushing chamber, and this continues until the material is conveyor will not be positioned correctly.
Kleemann Reiner
Rice. 12. Largest jaw crusher size
Kleemann Reiner company, which is consistently advertised on the Russian market, produces complete crushing equipment. The company offers to the market 15 models of jaw crushers (Fig. 12) for medium and coarse crushing for materials with a compressive strength of up to 320 MPa and three models for fine crushing, designed for materials with a strength of up to 500 MPa. All models use a complex swing pattern of the movable cheek.
Along with this, the company produces its own “rotary” series, consisting of five standard sizes of medium and coarse crushers.
The design (Fig. 13) differs from the known ones in the increased volume of the working chamber, which makes it possible to increase the percentage of cube-shaped grains. Two impact plates are located almost vertically, thereby reducing the number of collisions of crushed material in the chamber. The declared productivity of rotary crushers is from 170 to 900 t/hour.
Rice. 13. Impact crusher
Areas of use
Impact crushers are used to crush any materials that have low strength. This circumstance determines the areas of their application.
The main area of application of rotary crushers is the mining industry (production of crushed ore materials from natural stone, marble, as well as other sedimentary or igneous rocks, including coal). In addition, they are used for crushing grain in the production of animal feed and premixes, and for grinding straw and hay.
Impact crushers are widely used in the processing of industrial waste. The modification, by replacing the beaters with chopping knives, made it possible to create a universal crusher for processing a wide range of waste from various industries:
- polymer materials;
- rubber;
- timber processing;
- cardboard;
- skin;
- fabrics.
Polymer waste and rubber are processed into granules of a certain size. Polymer granules are again used for the production of products, and crumb rubber serves as a filler in the construction of highways.
Rotary wood crushers are essentially cutting machines for wood waste. Chopping knives grind waste lumber to a state suitable for the formation of briquettes or pellets, which serve as fuel in everyday life, for boiler houses and thermal power plants.
KRUPP FORDERTECHNIK
The undisputed leader in the European heavy equipment market, KRUPP FORDERTECHNIK, is represented by a comprehensive range of jaw and impact crushers, made according to classical designs. Almost all medium crushers have three types of design - stationary, semi-mobile and mobile.
It is necessary to pay attention to the Austrian crushing complex STARTRACK - 404 PCVG from HARTL (Fig. 14). Its functional purpose is more complex than crushing a homogeneous rock mass - it processes waste from the demolition of reinforced concrete and brick buildings. A rotor design with a rotor diameter of 1250 mm was chosen as a crusher.
The operating weight of the installation is 42 tons, it is capable of processing construction scrap up to 700 mm in size with a rated capacity of 350 tons per hour. The caterpillar chassis is equipped with a receiving hopper with a capacity of 8 m3, a vibrating feeder that is stepwise adjustable in transportation speed, a preliminary (before the crusher) vibrating screen that sifts out the fine fraction, an impact crusher, a diesel generator with a hydraulic control system for the actuators, a loading conveyor, a magnetic separator, and a control station. .
The crusher drive is a V-belt drive directly from the diesel engine. All other mechanisms, including tracked movers, receive torque from adjustable hydraulic motors of a single hydraulic system. The equipment set also includes a separate frame-mounted two-screen screen with three shipping conveyors, which are also driven by a single hydraulic system.
Despite all the undeniable progressiveness of the use of hydraulic systems, this design also revealed a real drawback in operating conditions in the cold season. Since the screen with conveyors is located at a significant distance from the central hydraulic system, its startup and operation at low temperatures (less than 10 ° C) is difficult.
HARTL
HARTL produces 2 standard size ranges of mobile crushers, one of which is equipped with jaw crushers, and the other with rotary crushers. Moreover, rotary ones are equipped with two fender plates and a rotor with 4 rows of beaters. The company's designers pay special attention to the problem of increasing the efficiency of using expensive metal in working parts. There are 4 different positionings of the same beater. Two beaters are installed in one row (along the width of the rotor).
Rice. 14. Crushing complex
After the start of operation, the beaters begin to wear out in the central part of the rotor, and there is almost no wear on the sides. Therefore, after the possibility of controlling the width of the discharge gap has been exhausted by changing the length of the fender plate rods, the two beaters are swapped, and the still unworn part of the beaters ends up in the center of the rotor. After abrasion of these parts, the beaters are turned over relative to their longitudinal axis. Since the beater bars are made asymmetrical, this makes it possible to practically use at least 38–40% of the beater metal.
Eagle Crusher Company
Due to the geographical remoteness, crushing equipment made in the USA is little known in Russia. Perhaps it only regularly reminds Russian consumers of itself at various construction forums. It is characteristic that the company practically switched to the production of exclusively semi-mobile plants, a priori expanding the field of action of such heavy equipment as stone crushing machines.
Equipped with an autonomous diesel drive, the rock crusher “lost” its previously inherent permanent residence in one quarry for its entire service life and turned into a highly mobile complex capable of crushing hard rocks at the place of their formation, changing location depending on the needs of crushed stone customers.
The standard size range of impact crushers consists of four units. The crushers are designed to handle the toughest materials including reinforced concrete, dolomite, basalt and mixed solid waste.
The Jumbo 1400 with four rows of beaters on the rotor and three adjustable impact plates was adopted as the basic design The rotor has a mass of 11 tons and a width of 1450 mm. The weight of the entire crusher is close to 20 tons. The supply of source material is provided by a vibrating screen feeder measuring 5.49 x 1.45 m, with a loading height of 4.72 m.
Rice. 15. Crushing complex “Mighty Max”
A 175 kW generator powers the plant and has reserve power to power an additional screen and a set of outfeed conveyors. The maximum possible productivity of such a machine does not exceed 540 t/hour.
Other representatives of this series - Mighty Max (Fig. 15), Jumbo 1000-15 UltraMax and Jumbo 1200-25 UltraMax - differ from the above only in smaller sizes and performance values.
Types of crushing plants
There are actually four of them. For small industries, jaw crushing plants . The rock is abraded between two plates (“cheeks”). Unfortunately, they are low-productive (100-400 t/hour) and require frequent repairs. However, their prices are quite high. The cost of the cheapest (used) starts from 400 thousand rubles. The most popular in this class is the PE series of units from the Chinese company LIMING.
Rotor complexes are presented no less widely. The powerful motor is very unpretentious and occasionally only needs to rewind the rotor wiring. Prices for such a “crusher” start at 1 million 900 thousand rubles. Although this again depends on whether the installation is new or has already been used. Perhaps the best in terms of price-quality ratio are Russian cars of the DR and SMD series . Many domestic companies are engaged in their production and sale under a certificate of conformity. When producing fine crushed stone, centrifugal impact units . By the way, they are universal and can be used as main equipment and as additional equipment. The initial cost of equipment is from 2 million 500 thousand rubles. company Barmac with a series of models (VSI) B.
The most expensive and high-performance devices are cone and hydraulic cone . They are capable of producing crushed stone of any fraction and even grinding the rock into sand. Prices for such cars reach 4 million rubles. Due to their versatility and reliability, the CS and CH series units from the Swedish company Sandvik are very popular.
By the way, the cost of mobile crushing complexes of even the lowest productivity (up to 60 t/hour) starts from 7 million rubles. So you will have to rack your brains over the choice. Although there is a leader here too - the Swedish company Jonsson .
Metso Minerals
A wide selection of crushing and screening equipment is represented by the Scandinavian association Metso Minerals , which recently operated on world markets under two independent leading mining brands Svedala and Nordberg, and now unites them.
A more detailed analysis of crushing equipment produced by Metso Minerals makes us note its undeniable technical and technological advantages.
Rice. 16. Jaw crusher Nordberg C125
of the Nordberg jaw crushers (Fig. 16) allows for the presence of structural stress raisers to be minimized, which has a beneficial effect on the overall reliability of the machine, which typically operates under variable loads.
The excellent kinematics of the crusher, ensured by the optimal grip angle, the steep angle of the spacer plate, the non-flat, shaped profile of the outer edges of the crushing plates and the increased speed of rotation of the flywheel, make the Nordberg C Series jaw crusher more productive than other crushers of similar sizes.
The Nordberg C series crusher is very convenient to work with and maintain. Inspection points and lubrication points are kept to a minimum. The size of the unloading gap is adjusted steplessly using a wedge mechanism.
Two adjusting wedges located towards each other, with their relative displacement, set and maintain the position of the movable cheek. This adjustment is very quick and safe and can be done even without stopping the crusher. It is possible to use both manual and electro-hydraulic drives of the adjustment mechanism.
Unlike hammer crushers, in which crushing of crushed stone occurs by hitting the material against hammers and reflective plates, Nordberg Barmac , produced by the Scandinavian engineering association Metso Minerals, have a number of undeniable technological and technical advantages for the production of fine fractions crushed stone with a cube-shaped grain from stone materials with a high degree of abrasiveness (Fig. 17).
Rice. 17. Nordberg Barmac rotary inertial crusher
Metso Minerals, using the Nordberg Barmac rotary inertial crusher, offers in the most economical mode to obtain crushed stone of granite, gabbroic and other abrasive rocks with a cubic index of 85–95% for small narrow fractions of 3–5 mm, 5–10 mm, 10–15 mm.
This is achieved by using the “rock-on-rock” impact crushing principle discovered and perfected by Metso Minerals, that is, the impact crushing principle with minimal wear on the working elements of the machine.
The fact is that the crushing chamber and the crusher rotor are lined directly with the processed material, and particles of the material are crushed by hitting each other, and not against the elements of the crusher.
One of the additional benefits of using a Nordberg Barmac crusher is the ability to produce cube-shaped material across the entire product range of 0–20 mm. That is, along with fractions 5–10, 10–15, 15–20 mm, it is possible to produce high-quality artificial granulated sand 0–5, which is successfully used at the asphalt plant as a filler.
also produces Nordberg NP (Fig. 18). When processing limestone and similar low-abrasive rocks, the TP series crushers, thanks to a specially designed crushing chamber profile and an improved rotor design with increased inertia, have a high crushing ratio and are very efficient.
Areas of use
Impact crushers are used to crush any materials that have low strength. This circumstance determines the areas of their application.
The main area of application of rotary crushers is the mining industry (production of crushed ore materials from natural stone, marble, as well as other sedimentary or igneous rocks, including coal). In addition, they are used for crushing grain in the production of animal feed and premixes, and for grinding straw and hay.
Impact crushers are widely used in the processing of industrial waste. The modification, by replacing the beaters with chopping knives, made it possible to create a universal crusher for processing a wide range of waste from various industries:
- polymer materials;
- rubber;
- timber processing;
- cardboard;
- skin;
- fabrics.
Polymer waste and rubber are processed into granules of a certain size. Polymer granules are again used for the production of products, and crumb rubber serves as a filler in the construction of highways.
Rotary wood crushers are essentially cutting machines for wood waste. Chopping knives grind waste lumber to a state suitable for the formation of briquettes or pellets, which serve as fuel in everyday life, for boiler houses and thermal power plants.
