The first step for the production of plastic wood is the collection of the raw material: plastic. At first you can use any type of plastic, however the most used are low density polyethylene and high density polyethylene. When plastic is separated before going to landfill, come cleaner, since it will not be mixed with all kinds of substances.. So having a selective collection structure is essential.
after collected, the plastic is separated by gender. Some companies separate white from colored plastic, since with white you can make light color profiles.
Then the plastic is washed and ground, forming granules (pellets). Case accurate, goes through a second wash
Production of Panels from Plastic-Wood Composite
More efficiency, economy and quality are the requirements of the panel producer market, made from plastic-wood composite.
There are three important steps that characterize this technology.
• Palltrusion – Plastic-wood composite production (WPC).
• Dispersion – from the WPC through an accurate dispersion system.
• Pressing – and material calendering with double tape press.
1ª Etapa
Natural fiber, especially wood flour, the plastic material in the form of granules, flakes, fibers or powder, as well as lubricants and other additives, are homogeneously dosed in this system.
Heat resulting from friction, and high pressure generated by the screw and agglomeration wing, agglomerate plastic to natural fiber.
Filaments of agglomerated material, formed in the process of passing through a perforated matrix, are then cut to the desired size, by a rotary cutting device.
1) rotary knives
2) perforated matrix
3) agglomeration wing
4) pressure piece
the mixing ratio, type of plastic material, type of natural fiber and its moisture content, are decisive factors in the performance of the equipment.
The use of gravimetric dosing technology increases system efficiency, ensuring a continuous material flow, keeping the quality of the granules produced constant.
Preferably, materials with a moisture content of up to 8%.
The steam generated in the agglomeration chamber, from the initial moisture of the natural fiber, is transferred to the atmosphere through a filter unit. Any fine material particles, sucked in by steam suction, are retained by the filter, discharged into the feed thread, thus returning to the agglomeration process. residual moisture, of the agglomerated material produced, will be below 1%.
This step consists of reprocessing the plastic. The granules are taken to a machine called an extruder, where they will be melted and homogenized. Pigments and fillers are normally added during the casting process, but they can also be placed together with the granules.. The extruder operates in various temperature ranges specified according to the type of plastic used..
2ª Etapa - Double Tape Dispersion and Pressing
Dispersion technology is used to distribute the granulate over the lower belt of the double tape press.
With the aid of a rigid blade, the sparger shaft cavities are filled with material. after ¼ back, counterclockwise, the material is brushed by a roller with bristles, this roller also turning counterclockwise. By the action of centrifugal force it slides along an inclined plane and is simultaneously distributed over the belt.
Efficiency and high quality in the production of WPC panels, it is only possible with the use of automatic technology.
To lower belt, longer, carries the WPC granulate which is evenly distributed. The bottom surface of the belt is in contact with the heating and cooling plates.
While the top plates are rigidly mounted, the upper ones move in a vertical direction together with the upper strap, in order to create a gap compatible with the required thickness of the panel.
One or more pairs of calibration rollers are mounted between the heating and cooling zones.