Technical Details of ZMEStructural GeometryThe base body is reverse‑thread with small lead. Multiple sets of through‑going tooth grooves are circumferentially cut on the screw flight. The tooth profiles of twin‑screws intermesh for mutual wiping and self‑cleaning. It delivers weak reverse conveying performance; materials travel forward by leakage flow. The inner bore is involute spline. Tooth positions must be aligned during installation; arbitrary mis‑aligned assembly is forbidden. Optimized fillet at tooth root reduces risks of material hanging and accumulation. Material Configuration- 38CrMoAlA Nitriding Steel: For general modification conditions
- WR5: For general high‑wear modification
- WR13: Wear‑resistant and corrosion‑resistant, for battery materials and corrosive systems
- Nickel‑base Alloy: For severe‑corrosion working conditions
Manufacturing ProcessIntegral forging followed by heat treatment; CNC milling for tooth grooves and thread profile. Intermeshing clearance is strictly controlled with smooth transition at tooth root. High intermeshing matching between twin‑screw tooth profiles is ensured to achieve reliable self‑wiping performance. Process Parameter Characteristics- Shear level: Low‑medium shear, lower than KB kneading block, slightly higher than SME
- Conveying capacity: Weak reverse conveying; materials advance by leakage flow, no positive pushing force inherently
- Shear heat: Medium, lower than KB kneading block, higher than SME
- Mixing type: Strong distributive mixing plus moderate dispersive mixing
- Residence time: Partially prolonged, controllable residence‑time distribution, no dead‑zone retention
- Self‑cleaning performance: Excellent. This is its key advantage over TME, suitable for frequent material and color change
| Functions of ZME•Build local back‑pressure and extend effective mixing time Reverse‑thread base generates back‑flow resistance and creates local melt back‑pressure, extending material residence time for sufficient mixing of additives and fillers. Materials are transported forward via leakage flow without complete blockage or screw stall. •Dual mixing: distributive and moderate dispersive performance Intermeshing tooth grooves repeatedly split and recombine melt streams, realizing radial and axial flow exchange. It achieves uniform distribution of composition and temperature, and mildly breaks agglomerates of fillers and glass‑fiber bundles. It balances distributive and partial dispersive capacity, provides better mixing effect than SME with gentler shear compared with KB kneading block. • Glass‑fiber wetting and mitigation of excessive fiber breakage Install ZME downstream of glass‑fiber side‑feeding section to improve resin wetting on glass fiber and break fiber agglomerations. Compared with KB kneading block, it retains fiber length to a greater extent, widely adopted for both long‑glass‑fiber and short‑glass‑fiber reinforced formulations. •Free of retention dead zones for color‑change and heat‑sensitive materials Full‑intermeshing self‑cleaning structure eliminates material retention dead zones existing in TME, reducing burnt and residual materials. It fits heat‑sensitive polymers and frequent grade & color‑change production, and lowers purging and cleaning workload. - Optimize devolatilization and venting performance Install upstream of vacuum devolatilization zone to continuously renew melt specific surface area and improve removal efficiency of small‑molecule volatiles.
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