​Machine classification

Machine classification

Blow molding machines can be divided into three categories: extrusion blow molding machines, injection blow molding machines and special structure blow molding machines. Stretch blow molding machines can fall into each of the above categories. Extrusion blow molding machine is a combination of extruder, blow molding machine and mold clamping mechanism. It consists of extruder and parison die, inflation device, mold clamping mechanism, parison thickness control system and transmission mechanism. The parison die is one of the important parts that determines the quality of blow molding products, and there are usually side feed die and central feed die. When large-scale products are blow-molded, the accumulator-type parison die is often used. The minimum volume of the storage tank is 1kg and the maximum can reach 240kg. The parison thickness control device is used to control the parison wall thickness, and the control points are up to 128 points, generally 20 to 30 points. The extrusion blow molding machine can produce hollow products with a volume ranging from 2.5ml to 104l.

Injection blow molding machine is a combination of injection molding machine and blow molding mechanism, including plasticizing mechanism, hydraulic system, control electrical appliances and other mechanical parts. Common types are three-station injection blow molding machines and four-station injection blow molding machines. The three-station machine has three stations for preform, inflation and demoulding, and each station is separated by 120°. The four-station machine has one more preforming station, and each station is separated by 90°. In addition, there are dual-station injection blow molding machines with 180° separation between the stations. The plastic containers produced by the injection blow molding machine are accurate in size and do not require secondary processing, but the mold cost is high.

The special structure blow molding machine is a blow molding machine that blows hollow bodies with special shapes and uses from sheets, molten materials and cold blanks as parisons. Due to the different shapes and requirements of the products produced, the structure of the blow molding machine is also different.