What is the difference between a main breaker and a feeder breaker
(I) Definitions
A main breaker is a key device responsible for the primary crushing task in a crushing system, typically positioned at the beginning of the crushing process. It is designed to break down large pieces of material into smaller particles, providing suitable feed sizes for subsequent crushing operations. Widely used in industries such as mining, metallurgy, and building materials, main breakers are characterized by high throughput, large crushing ratios, simple structures, and easy maintenance. Common types of main breakers include jaw crushers, cone crushers, impact crushers, gyratory crushers, roll crushers, and hammer crushers.
A feeder breaker is specialized equipment used in industries such as coal mining and general mining (especially open-pit mining). It is an integrated mining machine that combines crushing, feeding, and material conveying functions. A long-standing challenge for mining equipment is wear resistance, as it directly affects the service life of feeder breakers and the overall operational costs of mining. The core feature of a feeder breaker is the “through-type” flow of materials in the crushing chamber, where feeding, crushing, and discharging occur continuously, making it suitable for large-scale industrial production scenarios.
(II) Structure and Working Principles
Structural Design
(1) Feeding System
The feeding system of a main breaker requires a supporting independent vibrating feeder.
The feeding system of a feeder breaker integrates feeding devices such as chain plates and scrapers.
(2) Crushing Mechanism
The crushing mechanisms of main breakers are mainly jaw-type or gyratory-type:
The jaw-type crushing mechanism consists of a V-shaped chamber formed by a fixed jaw plate and a movable jaw plate.
The gyratory crushing mechanism consists of a conical crushing chamber.
The crushing mechanism of a feeder breaker is mainly a horizontal open crushing chamber, which is composed of a high-speed rotor and replaceable hammers or toothed rolls.
(3) Discharge Control
Discharge control of main breakers is manually adjusted by changing the gap between jaw plates.
Discharge control of feeder breakers is automatically adjusted by hydraulically adjustable screen plates.
Working Principles
Taking the jaw crusher as an example of a main breaker:
A jaw crusher mainly consists of a frame, eccentric shaft mechanism, crushing chamber, safety device, and discharge opening adjustment device. When the jaw crusher operates, the motor drives the belt and pulley, causing the movable jaw to swing back and forth and up and down via the eccentric shaft. When the movable jaw pushes the movable jaw plate toward the fixed jaw plate, materials are crushed or split. When the movable jaw retreats, the crushed materials are discharged from the lower discharge opening of the jaw plate.
Feeder breaker:
Composed of machined parts, castings, purchased components, and assembly parts, it is also composed of a chain conveyor and a crushing unit to combine feeding and crushing functions. For conveyor parts, materials are directly unloaded into the hopper by dump trucks, or can be unloaded into the hopper by bulldozers or loaders. Then, the feeder drive starts to operate, and the drive sprocket drives the chain to move horizontally in the conveying box while dragging the materials forward.
The working principle of the crushing unit is that when the chain and materials pass through the rotating toothed rolls in the crushing box, large pieces of materials that cannot pass through the specific gap between the toothed rolls and the bottom plate will be impacted, squeezed, and stretched by the rotating toothed rolls until they are broken into small pieces that are allowed to pass through. Feeder breakers can typically break large pieces of materials (800mm-1500mm) into medium-sized materials (200mm-500mm).
(III) Differences in Functional Positioning
Core Functions: The core function of a main breaker is to be responsible for the first-stage coarse crushing operation in a mine production line, while the core function of a feeder breaker is to be a continuous operation device integrating feeding and medium crushing functions.
Processed Materials: Main breakers process super-large raw ores directly transported from the mining site, while feeder breakers process pre-crushed medium-sized materials.
Typical Crushing Ratio: The typical crushing ratio of main breakers is 6:1 to 10:1, while that of feeder breakers is 3:1 to 5:1.
Representative Equipment: Representative equipment of main breakers includes jaw crushers and gyratory crushers, while representative equipment of feeder breakers includes chain-type feeder breakers and drum-type feeder breakers.
(IV) Application Scenario Selection
Main breakers: Due to their usually large feed openings and strong crushing capabilities, main breakers are more suitable for projects that need to process materials with high crushing ratio requirements and super-large sizes. They are commonly used in the coarse crushing section of new hard-rock mines and the primary crushing operations of stone crushing production lines and sand-making production lines in industries such as mining, building materials, and infrastructure. For example, jaw crushers can be used to crush ores and rocks of various hardness levels.
Feeder breakers: As mining equipment integrating crushing, feeding, and material conveying functions, feeder breakers are more suitable for secondary crushing in coal mines or medium-hard mines. They can be applied in various scenarios. For example, in coal mines, powerful grading feeder breakers can be used for crushing raw coal; in metal mines, they can be used for primary crushing of ores or for particle size control in the medium crushing stage, which can avoid re-crushing materials that meet the crushing particle size requirements and has good energy-saving effects. Feeder breakers can also be used in construction waste recycling treatment lines, mobile crushing stations, and underground mines with limited space.
In general, for new hard-rock mines, it is recommended to adopt a configuration scheme of “main breaker + feeder breaker”: first use a jaw or gyratory crusher for coarse crushing, and then use a feeder breaker for medium crushing. This combination can not only ensure processing capacity but also optimize product particle size. For projects such as coal mines and construction waste treatment, using a feeder breaker alone can meet production requirements.
(V) Economic Performance
(1) Investment Cost
Main breaker systems require supporting feeders, discharge conveyors, etc., resulting in higher total investment costs.
Feeder breakers have an integrated design with fewer auxiliary equipment requirements, resulting in lower total investment costs.
(2) Maintenance Cost
Replacing the jaw plates and liners of main breakers usually takes 8-12 hours, while replacing the hammers and toothed rolls of feeder breakers only takes 2-4 hours. Therefore, feeder breakers have lower maintenance time costs compared to main breakers.
(3) Service Life
The service life of main breakers processing hard rock is usually 10-15 years, while the service life of feeder breakers is usually 5-8 years. However, it is recommended to replace components such as rotors after 5 years.
(VI) Conclusion
Both main breakers and feeder breakers are important equipment in the entire crushing system, but they have differences in structural design, working principles, functional positioning, application scenarios, and economic performance. These two types of equipment have different application scenarios, and customers can choose and order according to the introduction in this article and their own needs.
