The JCSM710 is an integrated vertical air classifying mill designed specifically for dry grinding and shaping of natural flake graphite for lithium‑ion battery anode production. It combines impact grinding and built‑in turbo classification in one closed negative‑pressure unit, which is the core equipment to reduce raw flake graphite down to target D50 21–23 μm before spheroidization treatment.
Core Working Principle
- Feeding into grinding chamber
Pretreated dry natural flake graphite (low moisture, pre‑screened, low metal impurities) is continuously and quantitatively fed by a screw feeder to the centre of the high‑speed rotating grinding disc. The grinding disc carries distributed hammer/impact blocks, accelerating graphite flakes outwards into the annular grinding zone between rotating hammers and fixed gear ring. - Grinding and particle shaping by multi‑force combination
Natural flake graphite undergoes combined mechanical forces: high‑speed impact, inter‑particle collision, shearing and friction.
Unlike simple crushing that only cuts flakes into fragments, JCSM710 trims sharp edges of flake graphite simultaneously while reducing particle size. This controlled grinding avoids excessive over‑grinding into ultra‑fine submicron dust, which is critical to lock the D50 within 21–23 μm. The grinding intensity is adjustable via main spindle frequency control. - Air transport to upper classification zone
Under stable negative‑pressure airflow inside the mill, ground graphite powder flows upward into the top classification chamber with the circulating air stream. - Dynamic turbo classification
A variable‑frequency classifying wheel creates strong centrifugal force.
- Particles with target size (D50 21–23 μm) have enough airflow drag to overcome centrifugal force; they pass through the classifier wheel and go to cyclone collector and pulse dust collector as finished precursor powder.
- Oversized coarse particles are thrown outward by centrifugal force against the inner wall of the classification housing, then slide down back to the grinding chamber for re‑grinding.
Adjusting classifier wheel RPM is the primary method to fine‑tune the median particle size. Higher classifier speed cuts finer particles; lower speed allows larger particles to pass through.
- Closed negative‑pressure circulation
The whole system runs under negative pressure, preventing powder leakage and dust escape. Air circulates between grinding chamber, classification zone and fan. For battery‑grade graphite, the grinding liners, hammers and classifying wheel can adopt non‑metallic wear‑resistant materials to minimize iron contamination, protecting anode material purity.
Key Features for Natural Flake Graphite
- Grinding + shaping + classification in one machine: Saves separate classification equipment and maintains consistent particle morphology.
- Controllable particle size window: Perfectly matches the requirement of D50 21–23 μm precursor for natural flake graphite anode.
- Low over‑fine generation: Optimized impact geometry reduces excessive fines, which helps maintain good tap density in subsequent spheroidization.
- Batch stability: Frequency control on main motor and classifier wheel enables repeatable PSD for continuous mass production.
In the natural flake graphite anode line, JCSM710 serves as the primary milling stage. It breaks large raw flakes and shapes the sharp platelet edges to reach D50 21–23 μm precursor powder. The material then flows to spheroidization equipment for further rounding treatment to improve tap density and compaction performance for lithium battery anodes.
