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QINGDAO JBD MACHINERY CO., LTD
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In the extrusion of plastics, raw thermoplastic material in the form of small beads is gravity fed from a top mounted hopper into the barrel of the plastic pipe extrusion line. Additives such as colorants and UV inhibitors are often used and can be mixed into the resin prior to arriving at the hopper.
The material enters through the feed throat and comes into contact with the screw. The rotating screw forces the plastic beads forward into the barrel which is heated to the desired melt temperature of the molten plastic which can range from 200 °C (392 °F) to 275 °C (527 °F) depending on the polymer.
Extra heat is contributed by the intense pressure and friction taking place inside the barrel. In mostExtrusion equipment, cooling fans are present to keep the temperature below a set value if too much heat is generated.
Plastic extruder cut in half to show the components. At the front of the barrel, the molten plastic leaves the screw and travels through a screen pack to remove any contaminants in the melt. This breaker plate and screen pack combination also does the function of converting "rotational memory" of the molten plastic into "longitudinal memory".
After casual through the breaker bowl aqueous artificial enters the die. The die is what gives the final artefact its contour and have to be advised so that the aqueous artificial analogously flows from a annular profile, to the product's contour shape. Uneven breeze at this date would aftermath a artefact with exceptionable stresses at assertive credibility in the profile.
These stresses can could cause warping aloft cooling. Almost any appearance apprehensible can be created so continued as it is a connected profile. The artefact have to now be cooled and this is usually accomplished by affairs the extrudate through a baptize bath. Plastics are actual acceptable thermal insulators and are accordingly difficult to air-conditioned quickly. Compared with steel, artificial conducts its calefaction abroad 2000 times added slowly. In a Astro Turf Production Line, a closed baptize ablution is acted aloft by a anxiously controlled exhaustion to accumulate the anew formed and still aqueous tube or aqueduct from collapsing. For articles such as artificial sheeting, the cooling is accomplished by affairs through a set of cooling rolls. Once the artefact has cooled, it can be spooled, or cut into lengths for after use.
