Is the plastic extrusion molding in viscous flow state at a high temperature and a certain pressure, through a die having a specific cross-sectional shape, and then at a lower temperature, cross-sectional shape into a desired shape of a continuous profile molding Methods. Extrusion molding production process visual mold protection, is to prepare the molding material, extrusion molding and cooling, traction and cut extruded Ordnance Disposal (quenching or heat treatment). In the extrusion molding process, pay attention to adjust the heating section of the extruder barrel and head die temperature, screw rotation speed, traction speed and other parameters in order to get qualified extruded profiles. With particular attention to adjust the polymer melt extruded from the die head speed. Because when low melt extrusion rate, extrudate having a smooth surface, uniform cross-sectional shape; but when extruding the molten material reaches a certain speed limit, the surface of the extrudate becomes rough and dull appeared shark skin, orange peel, shape distortion and so on. When the extrusion rate is further increased, the surface of the extrudate distortion, or even fragmentation, and broken into pieces or cylindrical melt. Therefore, the extrusion rate control is crucial. Blow Molding is the prepared by the extrusion or injection, and is still in a plasticized state tubular or sheet stock material is fixed to the mold in the trend, and immediately pass into the air visual detection width, forcing the billet expands and paste in the mold cavity wall surface to be cooled after setting the release, that was a processing method desired hollow article. Suitable for blow molding of plastic high-pressure polyethylene, low-pressure polyethylene, rigid PVC, soft PVC, polystyrene, polypropylene, and polycarbonate. Depending on the preform molding method, extrusion blow molding is divided into injection blow molding and blow molding of two. Advantages of extrusion blow molding is a simple extruders and extrusion blow mold structure, the disadvantage is the parison wall thickness is inconsistent, likely to cause uneven thickness of plastic products. The right is extrusion blow molding Schematic. Advantages injection blow molding parison wall thickness is uniform, no flash, since the injection parison with bottom visual product batch testing, so the bottom of the hollow article will not fight and joints, not only beautiful and high strength. The disadvantage is the price of molding equipment and molds used expensive, so this molding method is used for the mass production of small hollow articles, in the absence of the use of a wide range of extrusion blow molding method. Visual detection width _ _ Shengding visual inspection instruments provided by the Dongguan City Ding Sheng Precision Instrument Company. Dongguan Sheng Ding Precision Instrument Co., Ltd. (www.dgshengding.com) (www.dgshengding.com) strong, credible, in Dongguan, Guangdong specialized instrumentation industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Shengding instrument into the brilliant and you work for a better future!