What is the working principle of a double roller crusher?The working principle of a double roller crusher (also known as a twin roller crusher) relies on the crushing force generated by the relative rotation of two rollers, which produces both compressive and shear forces to break down materials. Its core mechanism can be summarized as a process of “compression-grinding-controlled particle size.”
1. Core Crushing Mechanism
Material Entrapping and Compression
Material falls from the feed inlet between the two rollers and is drawn into the crushing chamber by the friction generated as the rollers rotate. The fixed roller and movable roller rotate at low speeds in opposite directions (typically with a linear surface speed < 4 m/s), applying high-pressure compression to the material, causing it to fracture.
Manner of Crushing Force Application
Compression Dominant: Smooth roll surfaces (standard in Huashengming models) primarily rely on compression to induce internal fractures and fragmentation, suitable for medium-hard materials (e.g., river pebbles, iron ore).
Shear Force Augmented: Toothed roll designs (e.g., Huashengming double-toothed roll models) enhance splitting and tearing effects, ideal for cohesive materials (e.g., coal, clay).
Discharge Control
Crushed material discharges through the gap between the two rollers under gravity. Gap size directly determines discharge particle size (typically adjustable from 1-50mm). A smaller gap produces finer discharge.
2. Structural Components and Workflow
The core structure of the Huashengming double-roll crusher includes:
Crushing Rolls
High-chromium manganese steel roll shells (incorporating patented rare-metal alloy composition) with a wear-resistant lifespan ≥2 years.
Fixed and movable rolls are installed in parallel; the movable roll can traverse laterally to adjust the gap.
Adjustment Mechanism
Hydraulic/Mechanical Adjustment: Precisely controls the roll gap (±1mm accuracy) by adding/removing shims or adjusting hydraulic cylinder pressure, enabling dynamic output particle size adjustment.
Spring Safety Device: Springs balance pressure between rolls during normal operation. Upon encountering hard objects (e.g., metal fragments), springs compress, causing the movable roll to retract and widen the gap for equipment protection.
Drive System
Dual motor drive (or single motor + spur gear) transmits power via V-belts/universal joints, ensuring counter-rotating rollers.
Huashengming’s new models feature an intelligent hydraulic system that automatically adjusts roller pressure and speed to accommodate material hardness variations.
Workflow
Feed → Roll Engagement → Crushing → Gap Discharge → Particle Size Screening (secondary crushing required for recycling).
3. Particle Size Adjustment Mechanism
| Adjustment Method | Principle | Applicable Scenarios |
|---|---|---|
| Shim adjustment | Adjust the number of shims between bearings to physically alter the roll gap width | Small spring machine models |
| Hydraulic cylinder pressure regulation | Dynamically control the roll gap by adjusting hydraulic pressure in real time (accuracy ±1mm) | Medium and large hydraulic machine models） |
| Worm gear mechanism | Manually rotate the worm gear to displace the movable roll | Traditional mechanical models |
4. Safety Protection System
Overload Protection
Upon encountering non-crushable objects, the movable roll automatically retracts via springs or hydraulic cylinders, widening the gap to expel foreign matter and prevent equipment damage.
Intelligent Monitoring
New models feature sensors monitoring temperature, pressure, and current, triggering automatic alarms or shutdowns during anomalies.
Wear-Resistant Protection
Thickened roller skin design + patented materials reduce replacement frequency (lifespan exceeds standard equipment by over 2x).
5. Performance Features & Advantages
| Features | Performance Advantages |
|---|---|
| Particle Size Control | Uniform discharge (needle and flake content <10%), low over-crushing rate, ideal for high-quality sand production. |
| Energy-Efficient and High-Performance | Layer crushing principle reduces energy consumption, saving 30%-45% electricity compared to impact crushers. |
| Multi-Material Compatibility | Compatible with river pebbles, iron ore, construction waste, etc., switching materials by adjusting the roll gap. |
| Low Maintenance Costs | Modular roll liners enable 1-hour rapid replacement; no other wear parts, reducing operating costs by 50%. |
6. Typical Application Scenarios
Manufactured Sand Production: Crush river pebbles into 1-3mm particles meeting Class II sand standards.
Mining Fine Crushing: Processes iron ore (compressive strength ≤200MPa) to 1-5mm output size.
Solid Waste Recycling: Crushes construction waste (including concrete blocks) to produce 5-10mm recycled aggregate.
Coal/Chemical Processing: Toothed roller models crush high-moisture coal gangue with anti-clogging design ensuring continuous operation.
