Custom TPV Extrusion Factories & Products

Although the continuous matrix of TPV is hydrophobic polypropylene, the dynamically vulcanized EPDM rubber phase, carbon black pigments, and mineral flame retardants absorb ambient atmospheric moisture rapidly. Extruding TPV with moisture content above 0.08% leads to splay marks, micro-voids, internal porosity, and localized profile collapse in vacuum cooling tanks. BAOD recommends desiccant hopper dryers operating at 75°C to 85°C with a dew point of -40°C for 2.5 to 3 hours immediately prior to screw entry.

TPV has a steep pseudoplastic shear-thinning curve. At high shear rates inside the die exit, rapid stress relaxation can cause the melt stream to tear at the die land exit, creating microscopic roughness called sharkskin. BAOD addresses this by designing screws with extended L/D ratios (30:1 to 32:1), low compression ratios (2.2:1 to 2.5:1), and smooth distributive mixing elements rather than aggressive dispersive pins. Concurrently, our dies incorporate longer parallel land lengths (typically 12:1 to 15:1 land-to-thickness ratio) with independently controlled tip heaters that lower exit melt viscosity and eliminate surface fractures.

Solid profiles and flexible bulb seals require different thermodynamic approaches. Hollow or semi-rigid profiles require vacuum calibration tanks equipped with precision brass or stainless steel dry-disc calibrators, where negative pressure pulls the hot TPV profile against the sizing geometry while chilled spray mist (12°C–18°C) solidifies the shape. Conversely, soft, foamed multi-durometer automotive bulb profiles cannot touch rigid calibrator walls without deforming; they utilize multi-stage open turbulent spray baths with submerged guide rollers and water level control to prevent elongation under puller tension.

While both materials can be processed on single-screw platforms, true interchangeability requires specific engineering considerations. Flexible PVC requires lower melt processing temperatures (150°C–175°C) and generates hydrochloric acid (HCl) if overheated, requiring chrome-plated or Hastelloy screws. TPV runs hotter (180°C–215°C) and requires higher drive torque and greater shear heating resistance. BAOD provides dual-purpose machines featuring bimetallic barrels, high-nickel alloy screws with universal flight profiles, and programmable dual-profile PID temperature software recipes for rapid material changeover.

Under our Global Service program, BAOD delivers turnkey machinery crated in vacuum-sealed rust-preventative packaging. We deploy senior bilingual commissioning engineers directly to customer facilities in North America, Europe, Southeast Asia, and South America for physical machine leveling, electrical connection verification, tooling alignment, and multi-day operator training. Remote technical support is facilitated via secure industrial IoT gateways for real-time PLC diagnostic access.