China Automobile PA Pipe Extrusion Line Manufacturer & Factories

Thermal Management in Electric Vehicles

The rapid shift to 800V battery architectures and multi-channel liquid glycol cooling requires lightweight, chemical-resistant polyamide pipes. Traditional EPDM rubber hoses are being aggressively replaced by corrugated and smooth PA12, PA612, and PA11 multi-layer tubes, slashing automotive vehicle weight by over 45% while resisting aggressive dielectric fluids and prolonged hydrolysis at sustained temperatures of 120°C.

• Direct glycol & dielectric coolant compatibility
• Vibration damping and zero ozone deterioration

Near-Zero Hydrocarbon Evaporation (CARB / LEV III)

Global environmental mandates, notably CARB LEV III and Euro 6d/7, strictly limit fuel system evaporative emissions. Monolayer tubing is incapable of meeting non-permeation criteria for alcohol-blended biofuels (E10 to E85). BAOD EXTRUSION lines co-extrude 3-layer to 5-layer structures incorporating EVOH (Ethylene Vinyl Alcohol) or fluoropolymer (ETFE/THV) barrier cores flanked by engineered tie-layers and modified PA12 skins.

• Fuel permeation < 0.5 mg/m²·day
• Superior burst resilience under pulsed pressures

Pneumatic Brake & Chassis Safety Architecture

Heavy commercial transport and passenger chassis rely on polyamide air-brake piping governed by stringent standard benchmarks like DIN 74324 and SAE J844. Tubing must exhibit unfailing mechanical burst stability from -40°C arctic conditions to +100°C engine compartments, absolute zinc-chloride resistance from road salts, and long-term plasticizer stability without micro-cracking.

• High plasticizer retention under thermal cycles
• Resistance to mechanical impact and micro-notch propagation

1. High-Torque Single-Screw Extruders

Equipped with specialized 30:1 or 34:1 L/D nitrided barrier screws engineered specifically for moisture-sensitive polyamide resins. Incorporates gravimetric loss-in-weight feeding hoppers and precision ceramic heater bands with independent air cooling chambers, guaranteeing melt pressure fluctuations within ±0.2 bar.

2. Co-Extrusion Spiral Die Technology

BAOD’s proprietary multi-channel spiral distributor die heads balance rheological dwell times across divergent polymer viscosities (such as PA12 vs. EVOH vs. functional maleic anhydride adhesives). Symmetrical stream distribution completely eliminates weld-lines, ensuring uniform radial layer distribution down to 0.05 mm thickness.

3. Vacuum Sizing & Controlled Quenching

Stainless steel SS304 dual-chamber vacuum calibrators deliver precise negative pressure regulated via frequency-inverter vacuum pumps. Multi-stage turbulent water spray nozzles ensure gradual, stress-relieving crystallographic quenching of the nylon polymer matrix, preventing ovality and residual internal hoop tension.

4. Closed-Loop Ultrasonic & Laser Feedback

Integrated multi-axis laser diameter gauges measure outer dimensions while high-frequency immersion ultrasonic sensors scan 360° wall thickness and layer concentricity in real time. The digital signal automatically feeds into the PLC to govern haul-off caterpillar speed and extruder screw RPM synchronously.

5. Multi-Track Servo Haul-Off & Pullers

High-precision multi-belt or caterpillar pullers with wear-resistant rubber belts grip the tube firmly without surface deformation or slip. Synchronized digital servo motors ensure zero vibration transfer back to the vacuum calibration tank, protecting continuous roundness at high line speeds.

6. Chip-Free High-Speed Rotary Fly Cutters

Automobile fluid lines mandate mirror-smooth cut faces without loose flash, chips, or dust that could later foul sensitive fuel injectors or ABS valves. Our servo-driven rotary flying knife cut-off units synchronize directly with linear extrusion speeds for crisp, perpendicular end finishes.