Ningbo Fangli Technology Co., Ltd. is a mechanical equipment manufacturer with over 30 years’ experiences of plastic pipe extrusion equipment, new environmental protection and new materials equipment. Since its establishment Fangli has been developed based on user’s demands. Through continuous improvement, independent R&D on the core technology and digestion & absorption of advanced technology and other means, we have developed PVC pipe extrusion line, PP-R pipe extrusion line, PE water supply / gas pipe extrusion line, which was recommended by the Chinese Ministry of Construction to replace imported products. We have gained the title of “First-class Brand in Zhejiang Province”.
PVC pipe extrusion equipment is the core equipment in plastic pipe production, and its performance directly affects the quality and production efficiency of the pipe. Today, let us take a detailed look at the main functions and working principles of this type of equipment to help everyone better understand this industrial equipment.
1. Raw Material Plasticization Function
The extruder must first fully mix and heat-plasticize raw materials such as PVC resin, stabilizers, and plasticizers. Through the rotation of the screw and the heating of the barrel, the raw materials gradually change from a solid state to a plastic state with fluidity, providing a qualified melt for subsequent molding.
2. Melt Conveying Function
During the rotation of the screw, the plasticized material is pushed forward by the conveying action of the screw flights. At the same time, the shearing action between the screw and the barrel further uniformly mixes and melts the material, ensuring stable melt temperature and pressure and providing a uniform material flow for pipe extrusion.
3. Pressure Control Function
The extruder needs to precisely control melt pressure to ensure stability during the pipe molding process. Excessive pressure may cause pipe deformation or rupture, while insufficient pressure may make the pipe surface unsmooth. Through the hydraulic system or screw speed adjustment, dynamic pressure balance can be achieved.
4. Pipe Molding Function
The melt that has undergone plasticization and conveying is molded into the required pipe shape through the die (head die) at the front end of the extruder. Different dies can produce PVC pipes of different diameters and different cross-sectional shapes, such as straight pipes and corrugated pipes. The precision of the die directly affects the appearance and dimensional accuracy of the pipe.
5. Cooling and Sizing Function
After extrusion, the PVC pipe needs to be rapidly cooled and sized, usually using a cooling water tank or spray cooling system. Rapid cooling can maintain the shape and dimensional stability of the pipe and prevent deformation or shrinkage caused by excessively high temperature. Cooling efficiency directly affects production speed and pipe quality.
6. Hauling and Cutting Function
After cooling, the pipe is hauled at a constant speed by the haul-off machine and enters the cutting equipment. The cutting system automatically cuts the pipe according to the set length to ensure that each pipe has a consistent length. The haul-off speed and extrusion speed need to be precisely matched to avoid tensile deformation or fracture of the pipe.
The above is an analysis of the main functions of PVC pipe extrusion equipment. A highly efficient extruder requires the coordinated operation of all systems to produce high-quality pipe products. In practical applications, operators also need to adjust parameters according to factors such as raw material characteristics and pipe specifications to achieve the best production results.