Characteristics of the main equipment and production of plas

Characteristics of the main equipment and production of plastic barrels which

 

   The main characteristics of equipment and production of plastic barrels, plastic barrels of production process, the equipment is very important. As the saying goes: we must first of its profits. Here to talk about the role and characteristics of plastic barrels of production equipment.

    1, and the extruder head: ordinary extrusion - blowing device Fundamental same.

    2, the parison disposal installation: the extruder tubular parison, to go through the installation stops cutting, bottom and neck fusion process to prepare a test tube bottomed parison.

    3, preform heating installation: install a variety of parison heating oven, heating sleeve, heating channels, etc., can be electric heating heating or infrared heating. But the heating installation to be able to balance the thermostat and heating, the temperature difference between inside and outside the parison minimized.

    4. Install a stretch stretching and stretching mandrel fixture two kinds.

    ① stretch mandrel: a mandrel stretching from the upper portion of the parison is inserted in the bottom of the hydraulic type action against the parison, the longitudinal stretching is stopped, then the pores on the mandrel into the compressed air blown through, stop radial stretch. Most of this stretching stretch forming installation are used.

    ② tensile fixture: clamps to stretch the ends of the tubular parison from external folders, stop longitudinally stretched by the hydraulic effect, stop and then blow radial stretch. Neck and bottom have flash needs trimming, burr crushed recyclable applications.

    5, jerrycans squeeze - pull - blow molding machine: There are many types of foreign and specifications squeeze - pull - blow molding machine, there is no special domestic equipment this

    Plastic barrels of production process: note - the practice by injection blow molding preforms and blow molded articles composed of two processes, and injection molded preform is key to the whole process of consumption.

    Process-controlled injection parison

    ① injection temperature: injection temperature and the type and characteristics of the injection molding machine type and thickness of products related to raw materials and other factors. Of crystalline resin, such as polyethylene, polypropylene, etc., the injection temperature should be above its melting point. Amorphous polymers such as polystyrene, polyvinyl chloride injection temperature is higher than its viscous flow temperature. Low resin melt batch number higher than the melt index of the resin injection temperature is higher. Using a plunger-type injection molding machine than the screw injection molding machine processing temperature is higher. Thin wall parison than the thick-walled preform injection temperature is high demand. Ordinary polystyrene injection temperature 140 ℃ ~ 240 ℃, polyethylene 150 ℃ ~ 280 ℃, polypropylene 205 ℃ ~ 285 ℃, polyvinyl chloride 160 ℃ ~ 190 ℃. Ordinary injection mold temperature is 40 ℃ ~ 80 ℃.

    ② injection pressure: ordinary resin melt index is low, the parison wall is thin, high pressure injection request, otherwise low. Plunger injection molding machine is higher than the pressure screw injection molding machine needs. In ensuring product quality situation, as far as possible the use of lower injection pressure. Ordinary polystyrene injection pressure 58.8 ~ 107.9MPa, polyethylene 58.8 ~ 98.06MPa, polypropylene 54.9 ~ 98.06MPa, polyvinyl chloride 78.4 ~ 127.5MPa.

    Blow molding and extrusion process control - blow molding of the same fundamental blow molding process.

    Major equipment and properties of the plastic barrel production: rectangular pipe (1) of the parison injection machine: Structure and ordinary injection molding machine of the same root, but the injection pressure is low, Screw can be smaller, the compression ratio should not be too large.

   (2) mold: including injection mold and blow mold. Parison injection mold and common injection mold the fundamental data and processing the same request, but must be a hollow mandrel in order to pass into the compressed air. Blow molds and extrusion - blow molding die simply the same.

   (3) release Installation: with extrusion - blow molding different, after the blow-molding process is completed, open the blow molds, the molded article with the mandrel to the stripping installation, the stripper plate and mandrel separate from the article.

   Product specification:

   Injection - blow-molded plastic bottles are currently no national standard and the Ministry of standard, product specification may refer to specification polyethylene blow barrels, and make the necessary corrections. But the same kind of raw material NOTE - Blow container than crowded - Excellent Blow container performance.

    Large hollow container volume of 50L or more generally refers to a variety of plastic body cooperage, tank, tank, tank and other large hollow products. Polyethylene resin-based raw materials, mainly for extrusion molding - blow molding and rotational molding.

    Extrusion - blow molding of large containers and plastic buckets fundamentally the same way, only a slight difference in raw materials and equipment.

    The main raw material request: consumption in ordinary plastic bucket or high-density polyethylene resins, low density polyethylene-based resin mixture, while the consumption of large container either high-density polyethylene and high molecular weight polyethylene resin-based.

    Major equipment and properties of the plastic bucket manufacturers: consumption of large containers are installed extruders and blow molding plastic barrels and consumer devices of the same, but it should be between the extruder barrel and an additional hopper head, see Figure 8 - 7 Because large parts of the parison is also great, if slow extruded from the extruder, parison is presented weight caused serious drawdown phenomenon, uneven wall thickness longitudinal formed products. At the same time due to long time out, the parison by cooling the temperature is too low, it will also affect the quality of the blow. After the installation of additional hopper, an extruder molten material continuously extruded hopper, when stored material reaches a certain amount, a material that is quickly pushed out by a pusher installed, constituting an average thickness, temperature appropriate parison . Thus not only reduce the additional accumulator parison drawdown, insisted parison temperature, but also with smaller extruder consumption of large products.