The Method Of Extrusion
For the production created by extrusion required for the production line the following equipment: extruders, the cooling element of the gauge, die, calibration table with a vacuum pump, pulling foster rolls, saws and equipment for laying and packing profiles. Profile is created directly from a homogeneous melt extruder based on supplied mixture. On extruders with two screws for the profiles are rarely used granules, usually a powder. The capacity of the extruder envy of the mass of pvc profile. On average, currently working system with a capacity of 300-500 kg / h and the rate of issuance of finished products from 3 to 5 m / min. An increase up to 700 kg / h throughput and die, respectively speed up 10metrov release profile in a minute. Number of screw speed should not be large, since a frictional processes possible overheating of the melt. Moulding mass reaches the optimum plastification at 180-200 degrees centigrade and high pressure (150-300 bar).
When injected into the calibration element extruder, especially in the first, the successful molding of pvc melt should have a low viscosity, but sufficient rigidity. Granular or powder enters the extruder through a special funnel. To funnel loaded entirely in hardware with a cylindrical auger dose volume powder was applied at each turn the screw. Special dispensers were installed for conical screws. This made it possible to incrementally adjust the capacity of the equipment. To ensure control and accurate setting capacity of equipment to improve the quality of profiles in our time, gravimetric dosing devices are completed and extruders with a cylindrical auger.