PVC Double Pipe Extrusion Line

Product Application

This production line is mainly used to produce PVC small and medium size pipe. The pipes are mainly used in for cold bending electrical casing and cable protecting, etc.etc.

Comparison of two sets twin pipe extruding line and one set quadruple pipe extruding line                                

1. Production range: quadruple pipe extruding line is mainly used to produce the φ16-φ32 mm conduit which is most popular and consumable in the market. The twin pipe extruding line can produce some bigger sizes pipes. 

2. Total installed power: based on similar capacity, the installed power of two production lines are similar.

3. Output: the output and efficiency of quadruple pipe extruding line is increased by 60% on the premise that the product quality is same as twin pipe extruding line.

4. Floor area: the occupied areas of the two production lines are almost same.

5. Labor cost: the operators for these two production lines are both two.

6. Power consumption: the power consumptions of these two lines are almost same.

7. Noise: after properly started, both of these two lines are almost no noise.

8. Summary based on customers’ feedbacks: compared with twin-pipe extruding line, the quadruple pipe extruding is easier to operate, what’s more, the product quality is more stable.

Production Flow

Raw material + additive → Mixing → material conveying → Forced feeding → Conical twin screw extruder → extruding mould → Diameter control unit → Spraying vacuum shaping box → spraying/immersion type cooling water tank → marking machine → caterpillar tractor → cutter → pipe expanding machine → Pipe stacker → pipe inspection & packing

1. Raw material mixing: add other auxiliary materials such as PVC stabilizer, plasticizer, antioxidant into high speed mixer according to process proportion, after high speed running, the material temperature will be increased to required process temperature through self-friction. Then the material will be discharged into cooling mixer to avoid plasticizing agglomeration. After cooling, the material will be manually sent to extruder or through conveyor.

2. Extruder: the extruder is fixed with quantificationally feeding device to match the extrusion amount and charging amount. As conical screw extruder, the diameter of feeding section is bigger, so the heat transfer area is big and shear velocity also high, therefore it is better for material plasticizing. The diameter of metering section is small, so the heat transfer area is small and melt shear velocity is low to extrude the melt at lower temperature. The feeding device and screw driving device are all controlled by inverter to achieve synchronous speed regulation.

3. Extruding mould: the pvc material from extruder will be pushed to mould by subsequent material. Mould is the critical part for pipe forming. Theoretically if the component or content of pipe is different, the mould is also different. So customers should choose the right mould according to the real product.

4. Vacuum shaping water tank is used for pipe shaping and cooling. The tank is made by stainless steel fixed with vacuum system and water circulating system for shaping and cooling. There are vertical and longitudinal regulating devices in the tank.

5. Tractor is used to continuously and manually haul out the formed pipe from mould. The tractor is controlled by CV inverter to achieve synchronous speed regulation with screw extruder. The stability of tractor has close relationship with pipe’s thickness uniformity. Huaming machinery has rich experience in design and manufacture, therefore we can satisfy all the customers.

6. Cutter: it will automatically cut and delay turn over after receiving the signal from limit switch or other length control device. The cutting procedure is synchronous with the pipe running. The cutter is driven by electrical and pneumatic device to carry out the cutting procedure. The cutter is fixed with suction device to recycle the scraps caused by cutting.

7. Reversing device is controlled by cylinder. It has limit device. When the pipe is cut, it will be transferred. After time delay, the cylinder will start to work so as to discharge the pipe. The reversing device will automatically reset through several second delay to wait for next circulation.

Technical Parameters

Detail pictures

Vacuum box

Video