Twin-shaft melt pump for double-wall corrugated pipe extruders

The twin-shaft melt pump performs the core functions of “pressure stabilization, metering, and pressure boosting” functions, particularly suited for high-viscosity materials like HDPE and dual-machine co-extrusion processes. They control extruder pressure fluctuations within ±0.5%, significantly enhancing pipe wall thickness uniformity and production stability while reducing host machine load by 20%–30%. These pumps are essential upgrade components for mid-to-high-end corrugated pipe production lines.

Core Functions

Pressure Stabilization & Wave Elimination: Eliminates pressure pulsations caused by screw speed fluctuations and uneven plasticization, stabilizing die inlet pressure to directly resolve wall thickness deviations and poor corrugation formation.

Precision Metering: Flow rate maintains linear correlation with speed. Combined with variable frequency drive, it achieves precise melt ratio control for inner and outer layers, supporting the “dual-machine co-extrusion, dual-layer diversion” process for double-wall corrugated pipes.

Load Reduction & Efficiency Boost: Independently handles pressure build-up, allowing the extruder to focus solely on plasticization. Increases output by 15%–30% while reducing degradation risks for heat-sensitive materials.

Superior Adaptability: Outperforms single-screw pumps in handling high-viscosity melts, recycled materials, and viscosity fluctuations across different resin grades, minimizing transition losses during material changeovers.

Working Principle

Two synchronously driven parallel gear shafts mesh to form a sealed chamber, drawing melt from the inlet and forcibly conveying it to the outlet. The dual-shaft design increases gear engagement area by approximately 40%, achieving higher volumetric efficiency. It also counteracts radial loads, allowing bearings to bear only torque, enabling long-term stable operation under high pressures exceeding 35MPa.

Applications

Large-diameter (DN≥300), high-ring-stiffness (SN8 and above) HDPE double-wall corrugated pipe production lines.

Twin-extruder co-extrusion processes demanding high precision in inner/outer layer ratio control.

Production with high recycled material content (>30%) or multi-variety/small-batch runs requiring frequent material changes.

Continuous 24-hour production requiring high equipment reliability and longevity.

Although dual-shaft melt pumps involve higher initial investment, they deliver significant overall benefits in product quality, production efficiency, and equipment lifespan. They are particularly suitable for double-wall corrugated pipe manufacturers pursuing premium quality and large-scale production. When selecting models, consider specific output requirements, raw material characteristics, and process demands. Adhere to the principles of “parameter matching, reasonable margin, and material compatibility” to ensure stable system operation.

Email: sale@meltpump.com

WhatsApp: +86 158 3833 1071

Any questions about our products, please feel free to contact us! We promise you high-end products and first-class service.Look forward to our cooperation!!!