Viknar’off has started a new production type. From now on, our plant manufactures PVC window profile. It is done using the extrusion method.
Extrusion is the process of manufacturing objects of cross-sectional profile out of the plastic mixture. During the process, the melted polymer material is pushed through a die of the cross-section.
Our extrusion systems have been developed by the GRUBER company engineers (Austria). The produced profile complies with the high standards of heat and sound insulation, strengths and design. Our profile systems are projected in the light of modern technologies and the latest window market tendencies.
Profile production process
High-quality PVC stock material and other ingredients (from European manufacturers only) are dosed in accordance with the classic formula and loaded into the Plasmec hot-cold mixer system. Mixing is done via hot and cold turbo mixers, creating the PVC-blend, so called COMPOUND. The system maintains constant mixing process, ensuring a stable quality of the output profile. After that the compound is loaded into Zeppelin (Austria) silos system with aeration, where it undergoes stabilization for 24 hours.
Next, the compound is fed to the extrusion line and worked under the pressure and high temperature inside the extruder. PVC profiles production line consists of an extruder, forcing the stock material through the die, a profile calibrator, a track link pulling the profile, marking equipment, a profile cutter and a packing machine.
Extruder melts the loaded powdery PVC-blend and forces the melted polymer under high pressure through the die. Dies and calibrators belong to the high quality equipment that forms the basis of the extrusion line. Our dies are manufactured by the world leader of the industry – an Austrian company GRUBER.
The product quality depends on the condition of dies and calibrators, therefore we have staff members whose duties are dies service and maintenance. The die temperature regime impacts the product quality (surface, dimensions) as well. To maintain the shape and size of the heated profile upon its exit from the die, it’s critical that it should be cooled at a certain speed. After the die, the shaped mixture gets into the calibrator, where it is shaped further and cooled. Shaping is done thanks to the vacuum in the die hollows, so that the melted PVC-mixture is drawn to die walls. This way of profile shaping is called a vacuum method.
For further profile shaping, it has to be cooled. This is done via cold water channels within the calibrator walls, and therefore it is called “a damp calibrator”. The water is poured over the warm profile, cooling it.
Our manufacture features a closed water-supply cycle. The water is loaded into a reservoir where it is cleaned, softened to a certain degree, cooled to +12 oC and then used again. The correct functioning of the cooling system has a great influence on the consistently straight profile shape.
At the next stage, the product is air dried and marked at each meter (№ of extruder, lot, production date). Then, gasket sealing and protective film is applied to the profile and it is pulled for cutting via the track link.
The cold PVC-profile is cut using slitting cutters. At the cutting point there is a vacuum cleaner to get rid of the dust. The profile is cut into “sticks” of the necessary length (6,5 m) and packaged for transportation. It is then stored in special stockrooms.
All extrusion processes need to be well coordinated to ensure high quality of the manufactured PVC-profile. We exercise strict control over all production stages. The profile quality control is carried out in our testing laboratory. Here, the following parameters are checked: Сharpy impact strength, cold impact resistance capability, angle joint solidity, linear dimensions change after heat impact.