PVC Pipe "One-to-Four" Production Line

A PVC pipe "one-to-four" production line refers to an extrusion setup where a single extruder simultaneously produces four PVC pipes. This design significantly improves production efficiency and reduces costs. Below is a detailed breakdown of the key components and workflow of this production line.

1. Core Components

1. Extruder System

• Single/Twin-Screw Extruder: Selected based on raw materials (PVC powder or pellets), equipped with heating and temperature control to ensure uniform plasticization.

• Die Head: A "one-to-four" split-flow die design ensures consistent wall thickness and diameter for all four pipes, requiring precision machining to avoid eccentricity.

2. Calibration & Cooling System

• Vacuum Calibration Tank: Four independent channels for calibration, using negative pressure to adhere the pipe outer wall to the calibration sleeve, ensuring roundness and dimensional accuracy.

• Cooling Water Tank: Multi-stage circulating water cooling to prevent pipe deformation.

3. Haul-Off Unit

• Four-Belt Haul-Off Machine: Synchronized traction for all four pipes, with adjustable speed to match extrusion speed and prevent breakage or accumulation.

4. Cutting & Stacking

• Automatic Cutter: Flying saw or planetary cutter for simultaneous or individual cutting, with adjustable length settings.

• Collection Rack: Sorting or bundling before stacking, optionally equipped with automated conveyors.

5. Auxiliary Equipment

• Mixing System: Optional automatic feeding and mixer for uniform PVC formulation.

• Printing/Marking Device: Online inkjet or hot stamping for labeling.

• Inspection Instruments: Optional laser diameter gauges or wall thickness detectors.

2. Workflow

1. Material Processing: PVC powder and additives (stabilizers, lubricants, etc.) are mixed and fed into the extruder.

2. Plasticization & Extrusion: Molten PVC is divided into four streams via the die head, forming pipe profiles.

3. Calibration & Cooling: The pipe profiles are initially shaped in the vacuum calibration tank, then fully cooled in the water tank.

4. Haul-Off & Cutting: All four pipes are synchronously pulled to the set length before cutting.

5. Packaging & Stacking: Automatic sorting or manual collection.

3. Key Technical Considerations

• Die Balance: Flow channel design must ensure uniform pressure and speed for all four streams to avoid wall thickness variations.

• Synchronization Control: High synchronization requirements for haul-off and cutting, typically managed by PLC or servo systems.

• Energy Management: While energy consumption increases compared to single-pipe production, unit costs decrease, necessitating optimized heating and cooling efficiency.

4. Applications & Advantages

• Suitable Products: Small-diameter PVC pipes (e.g., drainage pipes, electrical conduits, irrigation pipes, typically OD ≤110mm).

• Advantages: 3-4x higher output, lower labor and energy costs per unit, ideal for large-volume orders.

• Challenges: Higher initial investment, stricter die and maintenance requirements.