On production lines such as mineral processing and coal crushing, problems like uneven output particle size and excessive powder not only lower the product price, but also increase the energy consumption of grinding and the difficulty of separation.
How to achieve precise particle size control has become the key to improving efficiency and reducing costs.
This article will deeply analyze how the Mineral Sizers, with its unique design, can solve this problem.
What Is A Mineral Sizers?
A Mineral Sizers, as the name suggests, its core working components are two parallelly arranged and rotating disk rollers. The surface of the roller bodies is covered with specially designed tooth shapes (such as pointed teeth, flat teeth, comb teeth, etc.).
Unlike traditional crushing equipment, it does not rely on a single squeezing or impact force, but rather through the relative rotation of the two rollers, it exerts a "shear + compression + splitting" combined force on the materials entering the crushing chamber, achieving "selective crushing" of the materials - that is, only crushing the materials to the preset particle size, avoiding excessive crushing.
This unique crushing method gives it extremely strong adaptability. Whether it is hard iron ore, limestone, or viscous coal, wet and sticky materials, or easily frozen blocks of low-temperature materials, it can handle them efficiently.
From the primary crushing in mining, to the raw material pre-treatment in the building materials industry, to the resource utilization of construction waste in the environmental protection field, the Mineral Sizers can play a key role and become the core equipment of multi-industry crushing production lines.
How Does The Mineral Sizers Accurately Control The Material Particle Size?
The reason why the Mineral Sizers can achieve "precise micro-control" of the particle size lies in its three-dimensional adjustable parameters, which can be flexibly combined and adjusted according to the material characteristics and process requirements to ensure the optimization of the crushing effect.
Roller Spacing
The roller spacing is the core parameter that determines the output particle size. Its adjustment principle is similar to adjusting the cross-distance of scissors - the smaller the gap between the two rollers, the finer the particle size after the material is crushed; the larger the gap, the coarser the output particle size.
Different from the manual adjustment of traditional equipment, modern Mineral Sizerss are equipped with hydraulic or electric adjustment systems. Operators can input the target particle size value through the control panel, and the system will automatically drive the adjustment device to adjust the roller spacing. The adjustment process is fast (response time ≤ 3 seconds), precise (error ± 1mm), and no shutdown is required to complete the parameter change.
For example, in the beneficiation process, if the subsequent grinding stage requires fine-grained feed, the roller spacing can be adjusted to below 5mm; if used for pre-crushing, to produce larger particle materials, the roller spacing can be adjusted to 50-100mm, flexibly adapting to different process requirements.
Speed And Tooth Shape
In addition to the roller spacing, the adjustment of speed and tooth shape is an important supplement to achieve precise control of the particle size. It can be personalized optimized according to the material characteristics.
Speed Control: The rotational speed of the roller body directly affects the residence time of the material in the crushing chamber and the crushing intensity.
Increasing the speed will cause the material to be quickly discharged after entering the crushing chamber, with a short contact time with the tooth rollers, resulting in a relatively weaker crushing effect and a coarser output particle size; reducing the speed will prolong the residence time of the material in the crushing chamber, allowing for more sufficient shear and compression effects, resulting in a finer output particle size.
For example, when processing hard granite, the speed can be appropriately increased to avoid excessive crushing of the material, causing wear on the tooth rollers; when processing viscous lignite, the speed can be reduced to ensure adequate crushing of the material and reduce the phenomenon of blockage.
Tooth Shape Replacement: The tooth shape design is highly matched with the material characteristics and is the key to pre-control of particle size.
The Mineral Sizers can replace different types of tooth shapes according to the hardness, viscosity, and moisture content of the material:
pointed teeth (sharp tooth tips, strong penetration, suitable for hard and large-sized materials, such as iron ore, basalt, can quickly crush large pieces of material, reducing energy consumption);
flat teeth (smooth tooth surface, large contact area, suitable for materials with high viscosity and easy agglomeration, such as wet coal, clay, can prevent materials from sticking to the tooth rollers and avoid excessive crushing);
comb teeth (larger pitch, suitable for pre-crushing processes that require certain particle size separation, such as construction waste crushing, can effectively separate aggregates from impurities and ensure uniform output particle size).
Intelligent System
The "intelligent control upgrade" of the Mineral Sizers is its core advantage that distinguishes it from traditional equipment. Through the integration of sensors, controllers, and actuators, it has achieved a leap from "manual monitoring" to "intelligent closed-loop control". The workflow of the intelligent system is as follows:
Data Collection: The online granularity analyzer detects the particle size distribution of the output material in real time, the vibration sensor monitors the operating status of the roller body, the current sensor monitors the motor load, and the temperature sensor monitors the temperature of the key components of the equipment.
Data Processing: The controller receives data from various sensors and compares it with the preset particle size standards and equipment operation parameters to determine if there are any deviations (such as overly coarse particle size, excessive motor load, abnormal component temperature, etc.).
Data Recording and Analysis: The system will record the equipment operation parameters and output particle size data in real time, generating daily reports and monthly reports, providing operational personnel with a basis for process optimization. For example, by analyzing the data, it is found that for a certain type of material, the best particle size control effect is achieved at a rotational speed of 500 r/min and a roller spacing of 10 mm, and these parameters can be set as the default scheme, which can be automatically called for subsequent processing of similar materials, improving production efficiency.
Why EXCT Mineral Sizers Are Better Than Traditional Crushers?
In the selection of crushing equipment, jaw crushers (referred to as "jaw breakers") and hammer crushers (referred to as "hammer breakers") are commonly used devices in traditional schemes. However, both of them have inherent limitations in precisely controlling particle size, which cannot meet the requirements of modern production.
In contrast, the Mineral Sizers, with its unique working principle and structural design, demonstrates significant advantages in controlling particle size in the mineral processing process.
Jaw Crusher
The working principle of a jaw crusher is to use the periodic opening and closing of the moving jaw and the fixed jaw to crush the material.
Although it has advantages such as a large crushing ratio, simple structure, and high durability, its crushing process has obvious "intermittency" - the moving jaw completes one opening and closing before crushing a batch of materials.
This working mode directly leads to three problems:
first, the product particle shape is poor, mostly in the form of flakes and needles (due to the crushing force, the material breaks along the weak surface, making it difficult to form uniform particles);
second, the particle size distribution range is wide, with large particles and fine powder mixed together, and the proportion of qualified particle size is low; third, the over-crushing rate is high, as the uncontrolled crushing force causes some materials to be repeatedly crushed, resulting in a large amount of fine powder.
In addition, the adjustment of the discharge port of a jaw crusher relies on gaskets or wedges, with a limited adjustment range (usually only 10-100mm), and the adjustment process is cumbersome, unable to achieve continuous and precise particle size control, and difficult to adapt to the flexible requirements of different processes for the discharge particle size.
Hammer Crusher
The working principle of a hammer crusher is to use a high-speed rotating hammer head (with a rotational speed of up to 1000-3000r/min) to impact the material, causing it to break.
The core problem of this crushing method is that "the impact force is excessive and difficult to control":
on the one hand, the high-speed impact causes the material to be overly crushed, with a high proportion of fine powder (usually over 30%), which not only reduces the product value but also causes the target mineral to be lost in subsequent re-selection and magnetic separation processes, seriously affecting the separation efficiency;
on the other hand, the discharge particle size is affected by multiple factors (such as the wear degree of the hammer head, the particle size of the feed material, the gap of the screen plate, the motor speed, etc.), and the adjustment process is complex and has extremely poor stability
- for example, after the hammer head wears out, the impact force decreases, and the discharge particle size becomes significantly coarser; when the feed particle size fluctuates, the crushing effect will also change, making it difficult to maintain a stable particle size standard over the long term.
For industries such as mineral processing and coal deep processing that require high particle size precision, the defects of hammer crushers have become the key factor limiting the improvement of production efficiency.
The Advantage Of Particle Size Control Of The Mineral Sizers
Compared with traditional equipment such as jaw crushers and hammer crushers, the Mineral Sizers demonstrates overwhelming advantages in particle size control.
Its core competitiveness lies in the "precise, uniform, and intelligent" three dimensions, completely solving the pain points of traditional equipment.
Precise Regulation Mechanism
The core regulation logic of the Mineral Sizer is "the gap between the rollers determines the output particle size".
Through hydraulic or electric adjustment devices, continuous and precise adjustment of the roller gap can be achieved within a wide range of 0.5 - 200mm, with a control accuracy of ±1mm.
This adjustment method is like using a precise "caliper" to set the standard for the particle size of the material - as long as the target roller gap is set, after the material is sheared and compressed by the two disc rollers, it can form a particle size matching the roller gap, completely breaking away from the limitation of the fixed discharge port of the jaw crusher.
For example, in coal crushing, if it is necessary to produce fine coal below 10mm, the roller gap can be adjusted to 10mm, and the qualified particle size ratio can reach over 90%, much higher than the 60%-70% of the jaw crusher.
Uniform Particle Size Distribution
The unique tooth shape design of the Mineral Sizer (such as optimizing the tooth height, tooth pitch, and tooth tip angle) and the synchronous opposite-rotating motion mode of the two rollers ensure that the material receives uniform force in the crushing chamber.
After entering the crushing chamber, the material is "clamped" by the roller and gradually crushed until it reaches the particle size corresponding to the roller gap and is discharged. This avoids the problem of "repeated crushing" in traditional equipment.
Actual application data shows that the over-crushing rate of the Mineral Sizer can be stably controlled at below 5%, while the over-crushing rate of the jaw crusher and hammer crusher is usually as high as 15%-30%. Uniform particle size distribution not only improves product quality but also provides ideal feeding conditions for subsequent grinding and separation processes - grinding equipment does not need to handle excessive fine powder, and energy consumption is significantly reduced;
in the separation process, the uniform particle size of the material can ensure sufficient contact between the separation medium and the target mineral, improving separation efficiency.
Intelligent Closed-Loop Control
Modern Mineral Sizers have achieved "intelligent upgrade" by integrating online particle size analyzers, vibration sensors, current sensors, etc., and building a complete automatic control system.
Its working logic is as follows: The online particle size analyzer detects the output particle size in real time and transmits the data to the control system; the control system compares the detection results with the preset particle size values. If there is a deviation (such as coarse or fine particle size), it will automatically send instructions to the hydraulic/electric adjustment device to adjust the roller gap; at the same time, sensors monitor the operating parameters of the equipment (such as motor current, roller body vibration), predict changes in material load, and make parameter adjustments in advance.
This "detection - comparison - adjustment" real-time closed-loop control mode ensures the long-term stability of the output particle size, even in complex working conditions such as fluctuating feed particle size and changes in material properties, it can maintain the preset particle size standard, which is a technical advantage that jaw crushers and hammer crushers cannot achieve.
In summary, under the trend of the beneficiation process moving towards refinement and efficiency, the Mineral Sizers, with its precise particle size adjustment capability, uniform product distribution, and potential for intelligent control, is gradually replacing the traditional jaw crushers and hammer crushers in certain application scenarios.
Structure Composition Of The Mineral Sizers
The precise particle size control capability of the Mineral Sizer is inseparable from its refined, sturdy and precisely coordinated structural design.
The precise control of particle size by the double-disc roller crusher is inseparable from its refined, sturdy and precisely coordinated structural design.Each component is centered around the core requirements of "stability, accuracy and durability", ensuring the long-term efficient operation of the equipment. The main components and functions are as follows:
Transmission Device
Composed of explosion-proof motors, limit-type hydraulic couplings, reducers and drum-shaped gear couplings, it provides stable power for the roller.
The limit-type hydraulic couplings can buffer shocks, achieve flexible startup, and have overload protection functions;
the reducers use brands such as Frenard, SEW or equivalent, adopt a parallel shaft design, have a transmission efficiency of ≥ 96%, possess high overload capacity and an automatic temperature control system;
the drum-shaped gear couplings are equipped with safety pins and have a self-aligning function, are easy to install, and operate smoothly and reliably.
Roller Assembly
As the core crushing component, it is composed of roller bodies, gear sleeves/disk plates and shaft heads.
The roller bodies are made of high-strength materials, with gear shapes of eagle beak or knife type structures, and the material is ultra-high strength wear-resistant alloy, with a surface hardness of HRC 50–55, and impact toughness AK ≥ 48J/cm²;
the gear plates/disk caps can be replaced separately quickly, and some use imported cutting teeth (such as Lindometal), which are fixed reliably;
the roller bearings use SKF/FAG large clearance self-aligning roller bearings, combined with centralized automatic lubrication and dual sealing (mechanical labyrinth + fluorine rubber oil seal), effectively preventing dust and water, and extending service life.
Synchronous Gears
Installed at the tail of the roller, they adopt high-precision meshing design to ensure the synchronous opposite rotation of the two rollers, avoiding jamming and uneven force.
The gears are treated with carburizing and quenching, with high tooth surface hardness, stable transmission, and effectively guarantee the stability of the crushing tooth engagement position.
Casing And Base Support
The casing is a steel plate welding structure, with an inner lining of NM500 wear-resistant lining plates, with a service life of no less than 3 years;
the base support is cast iron or welded steel structure, with good rigidity. The inlet and outlet are equipped with flange-type sealing interfaces, combined with sealing felt and dust collection ports, effectively preventing dust overflow, meeting environmental protection requirements.
Features Of The Mineral Sizers
● Precise Granularity, High Yield
The Mineral Sizers adopts the unique principle of "pre-sieving", with the crushing teeth resembling a rotating sieve.
Before the material enters the crushing zone, particles smaller than the target granularity will pass directly through, while only oversized materials will be captured and crushed.
This selective crushing method fundamentally reduces over-crushing phenomena, ensuring uniform product granularity and an extremely high yield, effectively meeting your strict specifications for the final product.
● Durable And Easy To Maintain
The core crushing teeth are made of ultra-high-strength wear-resistant alloy steel and undergo precise casting and heat treatment. The surface hardness reaches HRC50-55, with excellent impact toughness, and have an extremely long lifespan.
At the same time, we adopt a modular design, and the wear-prone parts such as the gear sleeve and gear cap can be replaced quickly individually without disassembling the entire roller shaft. This means shorter maintenance time, less spare parts inventory, and thus significantly reducing your long-term operating and maintenance costs.
● Reduce Dust And Save Energy, Environmentally Friendly
Unlike traditional equipment that uses impact and compression for crushing, the Mineral Sizers relies on low-speed shearing and stretching forces to crush materials. This "gentle" crushing method requires less power and can reduce energy consumption by up to 20%. At the same time, as it avoids intense impact, the dust generation is controlled at an extremely low level, the working environment is cleaner, and it easily meets strict environmental protection standards.
● Overload Protection, Stable Operation
The equipment integrates a three-level overload protection system of mechanical, electrical, and sensing. The core torque-limiting hydraulic coupling can effectively buffer impact loads and automatically cut off power transmission when encountering non-crushable objects (such as iron). At the same time, the system supports automatic reversing function, which can quickly remove blocked materials, maximizing the protection of the crusher and drive unit, and ensuring the continuity and stability of production.
● Anti-Blocking Design, Highly Adaptable
The unique tooth arrangement and box structure design enable the equipment to have self-cleaning capabilities, effectively preventing material adhesion and blockage. Even when processing high-moisture and high-silt content materials, it can maintain smooth operation, ensuring a clear discharge port, and solving the problem of crushing damp materials.
Application Fields Of Mineral Sizers
Thanks to its outstanding particle size control capability and multiple advantages, the Mineral Sizers has been widely applied on a large scale in various industries, becoming a key crushing equipment:
Mining: It is used for crushing minerals such as coal, iron ore, limestone, granite, and basalt. It is particularly suitable for processes with strict requirements for over-crushing rate, such as crushing before coal sorting and before pre-selection of iron ore;
Mineral Processing: It provides uniform particle size for separation processes such as gravity separation, magnetic separation, and flotation, reducing fine powder loss and improving the recovery rate of target minerals, and is widely used in mineral processing plants for gold, silver, copper, iron, etc.;
Building Materials And Metallurgy: It is used for pre-treatment of materials such as cement raw materials (limestone, clay), sand and gravel aggregates, coke, and blast furnace slag, ensuring that the particle size of the materials meets the requirements of subsequent production processes, and improving the quality of building materials and the efficiency of metallurgical production;
Environmental Protection: In construction waste
Choosing a Mineral Sizers is not merely about purchasing a single piece of equipment; it is about introducing an advanced crushing process solution that can enhance the value of the final product and reduce the overall operating costs.
If you are seeking the best solution for the problem of material particle size control, we are more than willing to offer you professional technical consultation and customized solutions.
Contact our crushing experts immediately to obtain a customized particle size control solution, and empower your production capacity and efficiency!
