Equipment
Heavy-duty hydraulic extruder screen changer for continuous, high-pressure melt filtration with zero leakage and fast plate shifting.
Reference values for the model or models named above. The confirmed configuration, the capacity basis and the scope of supply are stated in the quotation and the drawings.
Overview
Filters unmelted gels, carbon specks, and foreign solid contaminants from continuous polymer melt under high pressure without melt leakage.
The Extruder Screen Changer (hydraulic continuous / non-continuous melt filtration system) is an indispensable component installed between the extrusion barrel and the pelletizing die head. Engineered to filter out solid impurities—such as unplasticized gels, carbon specks, degraded polymer particles, metal fragments, and foreign fibers—it safeguards downstream pelletizing dies and melt pumps against damage while guaranteeing high purity and melt stability in finished plastic pellets.
Fabricated from forged chromium-molybdenum alloy steel with high-temperature vacuum gas nitriding and precision micro-honing, the screen changer utilizes differential thermal expansion and precision metal-to-metal sealing to ensure zero polymer melt leakage under working pressures up to 350 bar. Powered by an independent high-pressure hydraulic station, screen changing occurs in less than 1.5 seconds, minimizing melt pressure fluctuations and keeping the extrusion line running at peak operational uptime.
Key features
Each picture names one part of the machine and what it does for the material and the batch.
Screen changer body forged from high-strength chromium-molybdenum alloy steel (38CrMoAlA / 42CrMo), vacuum heat treated and nitrided. Precision ground to tight tolerances, ensuring zero polymer leakage at melt pressures up to 350 bar and temperatures up to 330°C without mechanical packing seals.
High-performance hydraulic power unit equipped with high-pressure accumulator and variable-displacement pump. Shifts the screen plate/piston in less than 0.5 to 1.5 seconds, minimizing melt pressure fluctuation and preventing line starvation.
Hardened alloy steel breaker plates featuring tapered flow orifices and smooth polished counter-bores. Maximizes active filtration surface area, lowers pressure drop, and supports fine wire mesh against rupture.
Equipped with internal heating cartridges and external ceramic band heaters. PID closed-loop control guarantees uniform temperature across the flow channels, preventing cold spots, melt stagnation, and polymer degradation.
Integrated safety cage shrouds around the hydraulic pistons with mechanical/electrical safety interlocks. Shifting automatically inhibits if guards are removed, protecting operators from high-pressure pinch points.
Material and process
Read the conditions together: a machine is selected for the material and the output, not from its name alone.
Essential filtration auxiliary for all thermoplastic extrusion, recycling pelletizing, masterbatch, and compounding production lines.
Universally compatible with Polyethylene (HDPE, LDPE, LLDPE), Polypropylene (PP), Polystyrene (PS), ABS, PET, PA, and thermoplastic elastomers. Effectively filters out contaminants, degraded gels, carbonized specks, aluminum foils, paper fibers, and metal particles from post-consumer and post-industrial plastic melts.
The hydraulic screen changer performs continuous melt filtration; key boundaries include:
Accepts pressurized, plasticized molten polymer stream delivered directly from the single or twin screw extruder barrel discharge.
Melt entering the screen changer contains unmelted gels, foreign debris, metal specks, paper/wood fibers, or degraded polymer agglomerates requiring continuous removal before reaching the pelletizing die plate.
Delivers a thoroughly filtered, contaminant-free polymer melt flow at stable temperature and pressure.
Melt flows directly into downstream strand dies, water ring die heads, or underwater pelletizers without foreign particles that could cause die hole blockage or strand breakage.
Throughput
Read a figure together with the basis below it: the same machine reaches different numbers on different materials.
0.1–3 Ton/Hour
Screen changer melt throughput ranges from 80 kg/h up to 3,000+ kg/h depending on breaker plate filtration diameter (80 mm to 350 mm), single vs. dual filtration cavity design, and allowable maximum differential pressure (up to 250–350 bar).
Throughput is determined by polymer melt viscosity, operating melt temperature, filter mesh rating (e.g. 20 mesh for rough scrap vs. 150 mesh for clean spinning grade), and contamination loading rate. Highly contaminated post-consumer plastic scrap requires larger breaker plate diameters to maintain economic screen pack lifespan between shifts.
Models
The figures are the reference values entered for each model. The model for your line is confirmed against your material and output before it is quoted.
Scroll the table sideways to read every column →
| Model | Capacity range | Screen Area | Screen Diameter | Heating Power |
|---|---|---|---|---|
| NC-HWQ70 | 0.1-0.2 Ton/Hour | 38cm² | ø70mm | 4Kw |
| NC-HWQ100 | 0.15-0.35 Ton/Hour | 78cm² | ø100mm | 4Kw |
| NC-HWQ130 | 0.2-0.5 Ton/Hour | 132cm² | ø130mm | 4.5Kw |
| NC-HWQ160 | 0.3-0.75 Ton/Hour | 200cm² | ø160mm | 5.5Kw |
| NC-HWQ180 | 0.5-1.1 Ton/Hour | 254cm² | ø180mm | 6Kw |
| NC-HWQ210 | 0.5-1.35 Ton/Hour | 346cm² | ø210mm | 9Kw |
| NC-HWQ250 | 0.5-1.5 Ton/Hour | 490cm² | ø250mm | 10Kw |
| NC-HWQ300 | 1-1.8 Ton/Hour | 706cm² | ø300mm | 16Kw |
| NC-HWQ400 | 2-3 Ton/Hour | 1256cm² | ø400mm | 40Kw |
Scope of supply
The quotation states the scope for the confirmed configuration; the groups below describe how a supply is normally split.
Installation planning
These are the connections the machine and the line around it have to agree on before the layout is fixed.
Mechanical: Circular upstream entry flange bolted to the extruder barrel adapter; downstream exit flange mating to the pelletizing die head, melt pump, or diverter valve.
Electrical & Automation: Three-phase industrial power supply for hydraulic pump motor and multi-zone heating cabinet; digital alarm and shift confirmation signals integrated into extruder master PLC.
The buyer provides electrical power supply to the hydraulic power unit motor and heating zone controllers, hydraulic oil filling for the power unit, and adequate side clearance around the extruder centerline to allow hydraulic piston withdrawal during maintenance.
Spare parts
The parts that wear in normal service, and the spares worth keeping on site. How often a part is replaced depends on the material and the duty the machine runs, so the basis is confirmed for each machine.
Inspect for hole erosion, surface scoring, or deformation every 6–12 months; replace or re-face when flatness is compromised.
Multi-orifice support plate holding the wire mesh filter screen. Keep 2 to 4 spare breaker plates in stock.
Inspect for hydraulic fluid weeping along cylinder rods; replace seals every 12–18 months.
High-temperature fluororubber (FKM/Viton) seal kit for the hydraulic actuator cylinders.
Check electrical resistance quarterly; replace failed heaters immediately to maintain temperature uniformity.
Heating elements installed in the screen changer body and slide plates.
Calibrate semi-annually; replace if diaphragm is damaged or output signal drifts.
Pressure sensor installed upstream of breaker plate.
Blades, screens and other normal consumables are outside the standard warranty. How a spare part is identified and ordered is set out under Warranty & Spare Parts.
Selection
Work through what you already know. The rest is settled in the conversation, not before the first message.
Select the optimal screen changer architecture based on resin contamination level, line sensitivity, and output:
Request a Quote A model name, a material or a drawing is enough to start.
Tell us the material, the process and what you need to achieve. Technical details can be completed later together with our sales team.
