What is the Process of PVC Profile Extrusion Line

The process of PVC profile extrusion line mainly includes the following steps:

1. First, select the appropriate polyvinyl chloride (PVC) resin according to the performance requirements of the profile. Then select various additives, plasticizers, fillers (such as calcium carbonate), colorants, etc. to improve the processing performance and use performance of PVC.

2. Add PVC resin and various additives to the PVC high-speed mixer in a certain proportion and mix them thoroughly. When mixing, first mix the materials evenly at a low speed, and then gradually increase the speed to further mix the materials at a higher temperature. The general mixing temperature is around 100-120℃. The mixed materials are cooled to below 40-50℃ by the cooling mixer for storage and subsequent processing.

3. After the material enters the extruder from the hopper, it moves forward under the rotation of the screw of the conical twin-screw extruder. At the same time, the heating system of the PVC profile extrusion machine heats the barrel so that the material is plasticized at a gradually increasing temperature.

4. The profile blank extruded from the die first enters the vacuum setting table. In the vacuum shaping table, the air between the profile and the shaping mold is extracted by a vacuum pump, so that the outside of the profile is subjected to uniform negative pressure, so that it fits tightly on the inner wall of the shaping mold to achieve preliminary shaping.

5. The profile after vacuum shaping enters the cooling water tank for further cooling. The length of the cooling water tank is generally 3-5 meters, and the flow rate and temperature of the cooling water are adjusted according to the material and specifications of the profile.

6. The cooled profile is towed by haul-off unit. The traction speed should match the extrusion speed, generally in the range of 1-5 meters/minute, and is adjusted according to the specifications of the profile and the production capacity of the extruder.

7. When the profile is towed to a certain length, it is cut by a cutting machine to cut the profile into the required length. The accuracy of the cutting length is generally controlled within ±1mm.

8. The cut profile is visually inspected, mainly to check whether there are defects such as bubbles, scratches, deformation, color difference, etc. on the surface of the profile, and whether the cross-sectional size and shape of the profile meet the design requirements.