SMF Series Disc Grinding Pulverizer — High-Efficiency Plastic Milling System

Overview

The SMF Series Disc Grinding Pulverizer from Chenxing Machinery is an advanced disc-type plastic milling system engineered for converting thermoplastic pellets, flakes, and regrind into fine, uniform powder. Covering four models — SMF-400, SMF-500, SMF-600, and SMF-800 — the series delivers throughputs from 60 to 450 kg/h across a wide range of materials including PE, PVC, PP, ABS, PA, EVA, PET, PS, PPS, EPS, and PC.

Unlike conventional pulverizers that rely on cryogenic cooling, the SMF series achieves stable low-temperature grinding through an integrated air-and-water cooling system, preserving material properties while reducing operating costs. Its fully sealed, fully automatic workflow — from feeding to finished powder collection — makes it the go-to solution for plastic recycling lines, PVC compounding, rotational molding powder preparation, and masterbatch production.

Technical Parameters

All models support a broad material range suitable for PE pelletizing, PVC powder processing, and other applications.

System Configuration — In-Depth Component Breakdown

Core Features

1. New-Generation Disc Geometry — The redesigned disc tooth profile maximizes shear surface area while minimizing recirculation zones. Combined with Cr12MoV tool steel hardened to HRC 58–62, each disc set delivers 2× the service life of conventional designs under abrasive materials like glass-fiber-filled PP and PA.
   

2. High-Speed Bearing System — Purpose-built bearing assembly using precision-ground double-row spherical roller bearings, factory-calibrated for sustained operation at up to 3800 RPM. The hinged inspection door allows bearing inspection, regreasing, and disc-gap measurement without removing the motor or disc housing.
   

3. Totally Sealed Grinding Circuit — The entire grinding path, from the screw feeder through the cyclone and filter to the rotary valve discharge, operates under slight negative pressure. Zero dust leakage is guaranteed, meeting occupational health standards and eliminating housekeeping costs. Combined with our dust collection systems, the workshop environment stays clean even under 24/7 operation.
   

4. Fully Automatic Workflow — The PLC controller orchestrates automatic feeding (VFD screw), closed-loop grinding, pneumatic conveying, cyclone classification, rotary valve discharge, and oversized-particle return. Operators only need to top up the feed hopper and collect finished powder bags. Suitable for integration into a fully automated recycling plant.
   

5. Precision Gap Adjustment — Grinding disc clearance is adjusted externally via calibrated feeler gauges and fine-pitch adjustment bolts. Typical gap settings range from 0.15 mm (ultra-fine powder) to 0.50 mm (coarse throughput). Gap uniformity across the disc face is verified by a simple feeler-gauge drag test, requiring no laser alignment or specialized training.
   

6. Air + Water Combined Cooling — Unlike traditional cryogenic grinding that requires continuous liquid nitrogen supply, the SMF series uses forced-air circulation across the motor and disc jacket plus a closed-loop water circuit through the grinding chamber. This dual-mode system maintains material temperature well below the melt or degradation point of heat-sensitive resins (EVA, LDPE, EPS), preserving molecular weight and mechanical properties.
   

7. Broad Material Compatibility — One machine handles PE, PVC, PP, ABS, PA, EVA, PET, PS, PPS, EPS, PC, and their blends. Material changeovers are fast: open the hinged door, air-blow the grinding chamber, and swap the vibrating screen mesh — typically under 30 minutes. Ideal for toll grinding operations and multi-product compounding facilities.
   

8. Modular System Architecture — Each subsystem — feeding, grinding, classification, dust collection, and control — is independently accessible and replaceable. Customers can configure the exact specification needed: motor brand (Siemens WEG IE3-IE4), filter type (cartridge / bag), screen mesh size, and PLC feature set. The SMF also integrates seamlessly with upstream crushers, shredders, and downstream extruders or pelletizing lines.

Production Process

The SMF series operates as a continuous, closed-loop grinding system:

1. Material Feeding — Virgin pellets, recycled flakes, or pre-crushed regrind are loaded into the stainless steel feed hopper. The VFD-controlled screw feeder meters material at a preset rate into the grinding chamber.
   

2. Primary Grinding — Material enters the gap between two counter-rotating discs. The first disc stage (coarse-tooth zone) shears and fractures larger particles; the second stage (fine-tooth zone) further reduces particle size through intensive shear and friction.
   

3. Temperature Control — Throughout grinding, the water jacket absorbs frictional heat while the air-cooling fans dissipate motor and bearing heat. The PLC continuously monitors chamber temperature; if the setpoint is exceeded, feed rate is automatically reduced to prevent material degradation.
   

4. Pneumatic Conveying — The suction fan creates negative pressure that pulls ground powder out of the grinding chamber and into the cyclone separator. Airflow velocity is tuned to transport target-size particles while allowing oversize particles to drop back.
   

5. Primary Classification (Cyclone) — The cyclone separator spins the air-powder stream, causing denser powder particles to fall into the rotary valve. Lighter fines and dust continue to the bag filter stage. Typical cyclone capture efficiency: 85–92%.
   

6. Fine Dust Collection — Fine particles and dust enter the pulse-jet bag filter. PTFE-coated filter cartridges capture particles down to 1 μm. Compressed air pulses periodically clean the filters, dropping accumulated dust into the rotary valve. Exhaust air, cleaned to ≤ 10 mg/Nm³, is vented or recirculated.
   

7. Vibrating Screen Classification — Powder discharged from the rotary valve passes over a vibrating screen with customer-specified mesh. On-size powder flows into the finished product bag or collection bin. Oversized particles are automatically returned to the feed hopper for re-grinding, ensuring uniform particle size distribution.
   

8. Finished Product Collection — On-spec powder exits the vibrating screen into a collection bag or optional pneumatic conveying line leading to storage silos, mixers, or downstream processing equipment.

FAQ

1. What materials are the grinding discs made of, and what is their expected service life?

The SMF series discs are fabricated from Cr12MoV high-chromium alloy tool steel, vacuum-hardened to HRC 58–62 with a case depth of 2–3 mm. Under normal operation with unfilled PE or PP, disc life spans 12–18 months before re-grinding is needed. For abrasive materials such as glass-fiber-reinforced PA or mineral-filled PP, discs should be inspected every 6 months. The two-disc design allows individual replacement, halving maintenance costs compared to single-disc machines. Disc refurbishment (surface grinding to restore tooth profile) can be performed 2–3 times before replacement is required.

2. How fine can the SMF series grind, and how is particle size controlled?

With the appropriate screen mesh (20–200 mesh range), the SMF series reliably produces powder from 80 μm (≈ 180 mesh) to 800 μm (≈ 20 mesh). Particle size is primarily controlled by two variables: (a) grinding disc gap, set via feeler gauges and fine-pitch bolts (typical range 0.15–0.50 mm); and (b) vibrating screen mesh aperture. For rotational molding powder (typically 35 mesh / 500 μm), a 0.30 mm disc gap combined with a 35-mesh screen consistently yields D₅₀ within ±8% of target. Re-grinding of oversize is automatic, so the final product distribution is narrow and repeatable batch-to-batch.

3. How does the air-and-water cooling system prevent thermal degradation of heat-sensitive materials like EVA and LDPE?

Heat-sensitive materials soften or degrade when the grinding zone exceeds their Vicat softening point. The SMF addresses this with two independent cooling circuits: (a) a closed-loop water jacket cast into the grinding chamber wall, circulating chilled water at 5–15°C via an external chiller; (b) forced-air cooling across the motor housing and disc spindle. Together they maintain a stable grinding chamber temperature of 55–80°C even at full load. For ultra-sensitive materials such as EVA (Vicat ≈ 45°C), adding a refrigerated chiller with a 2–5°C setpoint brings chamber temperature below 50°C, enabling cryogenic-free powder production with zero material degradation.

4. How long does a material changeover take, and what is the cleaning procedure?

A complete material and color changeover typically takes 25–40 minutes with two operators. The procedure is: (1) stop feed, allow the machine to run empty for 2–3 minutes; (2) open the hinged door panel — no tools required — to access the grinding chamber; (3) use compressed air to blow residual powder from the discs, chamber walls, and screen deck; (4) swap the vibrating screen mesh if a different particle size is required; (5) purge the cyclone and bag filter with short compressed-air pulses; (6) close the door, restart, and feed the new material. The entire grinding path is accessible without removing the motor, minimizing downtime between production runs.

5. What is the energy consumption profile of the SMF series, and how does it compare to cryogenic grinding?

Cryogenic grinding systems consume liquid nitrogen at 0.5–1.5 kg per kg of product, representing a recurring cost of 0.50/kg at typical industrial LN₂ pricing — plus the electrical load of the LN₂ plant. The SMF series eliminates this entirely. Taking the SMF-600 (45 kW main motor + 7.5 kW fan + 1.1 kW rotary valve + auxiliaries ≈ 55 kW total installed power) producing 150–300 kg/h, the specific energy consumption ranges from 0.18–0.37 kWh/kg. At an industrial electricity rate of 0.018–30,000 versus cryogenic alternatives.

Why Choose Chenxing Machinery?

Chenxing Machinery, headquartered in Zhangjiagang City, Jiangsu Province, is a specialized manufacturer of plastic processing and recycling equipment with over 20 years of engineering heritage. We design, manufacture, and service a comprehensive range of machinery covering the entire plastics value chain:

• Crushers & Shredders — From single-shaft shredders to heavy-duty hammer mills

• Extruders — Single-screw, conical twin-screw, and parallel twin-screw configurations

• Pelletizing Lines — Strand, water-ring, underwater, and die-face systems

• Complete Recycling Lines — PE film washing, PET bottle-to-flake, rigid plastic recycling

• Profile & Pipe Extrusion Lines — Including WPC (wood-plastic composite) lines, PVC pipe lines, and custom profile lines

• Auxiliary Equipment — Mixers, loaders, vibrating screens, chillers, dust collectors

Every SMF disc grinding pulverizer undergoes a factory acceptance test (FAT) before shipment, including a 4-hour continuous run with the customer's specified material. We maintain a comprehensive spare parts inventory for same-day dispatch, and our engineering team provides remote video assistance for commissioning, troubleshooting, and operator training. Explore our full product catalog, browse industry solutions, or read our latest news and case studies for application insights.

Request a Quote — 4 Simple Steps

1. Tell Us Your Material — Specify the type(s) of plastic (PE PVC PP ABS PA EVA PET PS PPS EPS PC), incoming form (pellets, flakes, regrind), and desired output particle size (mesh or micron).
   

2. Define Your Throughput — Indicate your target hourly output. We'll recommend the optimal SMF model (SMF-400 through SMF-800) or engineer a custom solution.
   

3. Receive a Tailored Proposal — Within 24 business hours, you will receive a detailed quotation including machine specifications, configuration options (motor brand, filter type, automation level), shipping terms, and estimated delivery lead time.
   

4. Start Production — After order confirmation, we conduct a pre-delivery test run, ship the complete system, and provide on-site or remote commissioning support to get you into full production.

Contact us today

• Email: ceo@cxsljx.com

• Phone / WhatsApp: +86 159 5118 7228 (Nicole)

• Company: Zhangjiagang Chenxing Machinery Co., Ltd.

• Website: https://chenxingmachinery.com