A industrial rock crusher, also known as a crushing machine, is mechanical equipment that breaks large-sized solid materials into specified particle sizes by causing brittle deformation through external force. It is widely used in various fields such as mining, construction, road building, and construction waste recycling, serving as the core equipment for sand and gravel aggregate production, ore processing, and solid waste resource utilization. As a key type of industrial rock crusher, it plays an irreplaceable role in modern material processing industries.

I. Core Working Principles of Crushers

The essence of a crusher's operation is to use mechanical force to overcome the internal bonding force of materials, breaking them from whole into small pieces. Based on the different forms of acting force, it is mainly divided into the following categories:

• Compression Crushing: Extrudes materials through the relative movement of two working surfaces, causing compressive fracture and bending failure. Typical equipment includes jaw crushers and cone crushers;
• Impact Crushing: Breaks materials by using high-speed moving parts (such as hammers and blow bars) to impact materials, or by making materials collide with each other at high speed. Typical equipment includes impact crushers and vertical shaft impact (VSI) crushers;
• Grinding Crushing: Achieves fine crushing through friction and grinding between materials and grinding media. It is commonly used in equipment such as ball mills and can also be used as an auxiliary crushing form for crushers.

II. Main Classifications of Crushers

According to the crushing stage, structural form and application scenario, crushers can be divided into multiple categories. The three most widely used categories are as follows:

1. Jaw Crusher (Primary Crushing Equipment)

The jaw crusher is the most traditional and commonly used crushing equipment, mainly used for primary crushing of materials. Its structure consists of a fixed jaw plate and a movable jaw plate forming a crushing cavity. The eccentric shaft drives the movable jaw plate to make reciprocating swings, squeezing and splitting large materials entering the crushing cavity. This equipment has a large feed opening, can handle various hard rocks with compressive strength below 320MPa (such as granite and basalt), and is widely used in the primary crushing link of mines and quarries.

2. Cone Crusher (Medium and Fine Crushing Equipment)

Cone crushers are mainly used for medium and fine crushing of materials, including spring cone crushers and hydraulic cone crushers. Their core working components are the movable cone and the fixed cone. The movable cone makes a swinging motion driven by the eccentric sleeve, squeezing, rolling and shearing the materials clamped in the crushing cavity. This equipment has a large crushing ratio and uniform finished product particle size, suitable for processing ores and rocks with compressive strength below 300MPa, and is the core equipment in the medium and fine crushing link of sand and gravel aggregate production lines.

3. Impact Crusher (Medium Crushing and Shaping Equipment)

Impact crushers rely on high-speed rotating blow bars to impact materials. After hitting the impact plate, the materials rebound and collide with subsequent feed materials to achieve multiple crushing. The finished products are cubic with low needle and flake content, which can not only complete medium crushing but also shape materials. It is suitable for processing soft rocks, construction waste, limestone and other materials with compressive strength below 180MPa, and is often used in the production of sand and gravel for road construction.

III. Application Scenarios of Crushers

The application of crushers covers multiple industries, with core scenarios including:

• Mining: Processing various ore raw materials to provide materials meeting particle size requirements for mineral processing and smelting links;
• Construction Engineering: Crushing large stones into sand and gravel aggregates for the preparation of concrete, mortar and road bases;
• Construction Waste Recycling: Crushing and recycling solid wastes such as concrete blocks and bricks generated from demolition and construction to realize resource recycling;
• Road Construction: Producing crushed stone and manufactured sand that meet specifications to meet the material needs of infrastructure projects such as highways, railways and airports.

IV. Differences Between Mobile Crushers and Fixed Crushers

In addition to traditional fixed crushers (which require the construction of fixed foundations and are suitable for large-scale production lines), mobile crushers have been increasingly widely used in recent years. It integrates crushing, screening and conveying systems on a movable frame or crawler chassis, without the need for fixed foundations, and can be directly driven to the job site. It is especially suitable for scenarios such as decentralized processing of construction waste, operation of remote quarries and temporary engineering materials, and has the advantages of flexible movement, quick commissioning and low transportation costs.

V. Summary

As the core equipment for material crushing and processing, the selection of crusher type must be determined based on factors such as material hardness, crushing particle size requirements and application scenarios. From traditional fixed equipment to new intelligent and mobile equipment, the technological development of industrial rock crushers has always focused on efficiency, energy saving, environmental protection and flexibility, providing key technical support for the development of mining, infrastructure, solid waste treatment and other industries.

How Does an Industrial Rock Crusher Work?

An industrial rock crusher is the core material crushing equipment in fields such as mining, infrastructure and solid waste treatment. Its core mission is to overcome the internal bonding force of materials through mechanical external force, breaking large-sized solid materials into particle sizes required for industrial production. Different types of industrial rock crushers have significant differences in working principles due to differences in structural design and application scenarios, but essentially, they all use mechanical forces such as compression, impact, grinding and splitting to break materials. This article will detail the working principles and applicable scenarios of mainstream industrial rock crushers.

I. Core Crushing Force Types of Industrial Rock Crushers

Regardless of the type of industrial rock crusher, its crushing process relies on one or more of the following mechanical forces, which is the basis for understanding its working principle:

• Compression Force: Extrudes materials through the relative movement of two working surfaces, causing materials to fracture due to insufficient compressive strength. It is suitable for primary and medium crushing of high-strength materials such as hard rocks and ores;
• Impact Force: Uses high-speed moving parts (such as hammers and blow bars) or the high-speed movement of materials themselves to generate impact, causing brittle fracture of materials. It is suitable for crushing and shaping medium and soft materials;
• Grinding Force: Achieves fine crushing through friction and grinding between materials and grinding media, and between materials themselves. It is often used in the final crushing link of materials;
• Splitting Force: Applies splitting force to materials using sharp components, causing materials to crack along textures or weak surfaces. It is mostly used as an auxiliary force for compression crushing.

II. Detailed Explanation of Working Principles of Mainstream Industrial Rock Crushers

1. Jaw Crusher: Primary Crushing Equipment Dominated by Compression + Splitting

The jaw crusher is the most widely used primary crushing equipment, with core structures including fixed jaw plate, movable jaw plate, eccentric shaft, flywheel and other components. Its working principle is as follows:

The motor drives the eccentric shaft to rotate through a V-belt, and the eccentric shaft drives the movable jaw plate to make reciprocating swings around the suspension shaft, causing the space of the crushing cavity between the movable jaw plate and the fixed jaw plate to change periodically. When the movable jaw plate approaches the fixed jaw plate, the large materials entering the crushing cavity are squeezed, split and bent until they break into small pieces that meet the discharge particle size. When the movable jaw plate moves away from the fixed jaw plate, the crushed materials are discharged from the discharge port under the action of gravity. The whole process cycles repeatedly to achieve continuous primary crushing operations. This equipment has a large feed opening, can handle hard rocks such as granite and basalt with compressive strength ≤320MPa, and the discharge particle size can be controlled by adjusting the jaw plate gap.

2. Cone Crusher: Medium and Fine Crushing Equipment Dominated by Compression + Rolling

Cone crushers are divided into spring cone crushers, hydraulic cone crushers and other types, and are the core equipment for medium and fine crushing of hard rocks. Their working principle is:

The core components of the equipment are the movable cone and the fixed cone, which form an annular crushing cavity. The motor drives the eccentric sleeve to rotate through the transmission device, and the eccentric sleeve drives the movable cone to make a swinging motion. There is an eccentricity between the axis of the movable cone and the axis of the fixed cone. When the movable cone approaches the fixed cone, the materials in the crushing cavity are squeezed, rolled and sheared, resulting in fracture. When the movable cone moves away from the fixed cone, the crushed materials fall to complete a crushing cycle. The hydraulic cone crusher is also equipped with a hydraulic cavity cleaning and overload protection system. When uncrushable objects enter the crushing cavity, the hydraulic system can jack up the movable cone, discharge the foreign objects and automatically reset to ensure the stable operation of the equipment. Cone crushers have a large crushing ratio and uniform finished product particle size, suitable for medium and fine crushing of ores and rocks with compressive strength ≤300MPa.

3. Impact Crusher: Medium Crushing and Shaping Equipment Dominated by Impact + Collision

Impact crushers focus on medium crushing and material shaping, with core structures including rotor, blow bars, impact plates, feed port and other components. Their working principle is as follows:

The motor drives the rotor to rotate at high speed (rotating speed up to 1000-1500r/min), and the blow bars on the rotor move at high speed synchronously with the rotor. When materials enter the equipment from the feed port, they are first impacted by the high-speed rotating blow bars. The materials that obtain kinetic energy collide with the impact plate at high speed, rebound and collide with subsequent incoming materials. At the same time, the materials will also be squeezed and ground between the blow bars and the impact plate. After multiple impacts, collisions and extrusions, the materials are gradually broken into the specified particle size and discharged from the discharge port. The finished products of impact crushers are cubic with low needle and flake content, suitable for crushing limestone, construction waste, gangue and other materials with compressive strength ≤180MPa.

4. Vertical Shaft Impact (VSI) Crusher: Sand Making Equipment Dominated by Impact + Grinding

The vertical shaft impact (VSI) crusher (commonly known as sand making machine) is the core equipment for manufactured sand production. Its working principle is divided into two modes: "stone-on-stone" and "stone-on-iron":

• Stone-on-Stone Mode: After entering from the feed port, the materials are divided into two parts by the distributor. One part enters the center of the high-speed rotating impeller and is accelerated and projected out under the action of centrifugal force, colliding violently with the other part of the materials falling from the periphery of the distributor. At the same time, the materials will also collide with the wear-resistant lining plate of the crushing cavity, realizing crushing through mutual collision and grinding;
• Stone-on-Iron Mode: After being accelerated and projected by the impeller, the materials directly collide with the wear-resistant iron blocks in the crushing cavity, realizing crushing through impact and rebound. The crushing efficiency is higher, but the wear of wear parts is faster.

The VSI crusher has fine discharge particle size and reasonable gradation of finished sand, mainly used for sand making from hard rocks such as granite and basalt, meeting the particle size requirements of construction sand.

III. Key Factors Affecting the Working Efficiency of Industrial Rock Crushers

While understanding the working principle, it is necessary to pay attention to the core factors affecting crushing efficiency to optimize the equipment operation effect:

• Material Characteristics: The compressive strength, moisture content and mud content of materials directly affect the crushing effect. Excessively high moisture content is likely to cause material blockage in the crushing cavity, and excessively high hardness will increase equipment wear;
• Equipment Parameters: Rotor speed (impact crusher, VSI), crushing cavity gap (jaw crusher, cone crusher), and the wear degree of blow bars/jaw plates need to be adjusted to the optimal parameters according to material characteristics;
• Feed Particle Size: The feed particle size must match the equipment design requirements. Excessively large size is likely to cause overload shutdown, and excessively small size will reduce crushing efficiency.

IV. Summary

The working principle of industrial rock crushers revolves around the core of "breaking materials by mechanical force". Different types of equipment adapt to material crushing scenarios with different hardness and particle size requirements by combining forces such as compression, impact and grinding. Jaw crushers focus on primary crushing, cone crushers focus on medium and fine crushing of hard rocks, impact crushers take into account medium crushing and shaping, and VSI crushers specialize in sand making. Mastering their working principles is the key to reasonable selection, optimizing operating parameters and improving crushing efficiency.