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Company Name: Taizhou Huangyan Yige Machinery Co., Ltd. Contact: Manager He Phone: 15967672923
Company mailbox: 2562261439@qq.com
Company Address: Shangye Industrial Zone, Jiangkou Street, Huangyan District, Taizhou City

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Technology and market development of automatic blow molding machine
Edit:Taizhou Huangyan Yige Machinery Co., Ltd.   UpDate:2019-04-02

In recent years, PET blow molding bottles have been widely used for beverage packaging, especially carbonated beverage packaging (such as Cola, etc.) due to their light weight (accounting for 1/10 of equal glass bottles), high strength, transparency, and non-toxicity. It is a sudden rise. In addition, because the packed glass beer bottles have repeatedly suffered injuries due to explosions, foreign countries have already switched to PET bottle packaging, so the PET blown bottle market has a bright future.

The production of PET blow molding bottles can be divided into two types of molding methods: injection stretch blow molding (referred to as injection stretch blow) and extrusion stretch blow molding (referred to as extrusion stretch blow) according to the preform of the parison. The process of injection stretch-blowing is as follows: the bottomed preform is shot first, and after cooling, it is continuously sent to the heating furnace (infrared or electric heating) by the conveyor belt, heated to the stretching temperature, and then returned to the blow mold by stretching rod Axial stretching, finally blow molding. The author discusses the influencing factors of the reheating, stretch blow molding process of preformed preforms. The company mainly produces fully automatic blow molding machines.

The blow molding process is a biaxial stretching process. In this process, the PET chain is bidirectionally extended, oriented and placed, thereby increasing the mechanical properties of the bottle wall, improving the tensile, tensile, and impact strength. Good air tightness. Although stretching helps to increase strength, it should not be stretched too much. It is necessary to control the stretch inflation ratio; do not exceed 3.5-4.2 in the radial direction and 2.8-3.1 in the axial direction. The wall thickness of the preform should not exceed 4.5mm.

Blowing is performed between the glass transition temperature and the crystallization temperature, and is generally controlled between 90-120 degrees. In this interval, PET appears as a highly elastic, fast blow molding, cooling and shaping into a clear bottle. In the one-step method, this temperature is determined by the cooling time in the injection molding process, such as the Aoki bottle blowing machine, so the connection between the injection and blowing stations must be well connected.

The blow molding process includes: stretching-one blow-two blows, the three action moments are very short, but they must be well coordinated, especially the first two steps determine the overall distribution of the material, the quality of the automatic blow molding machine Good or bad. Therefore, it is necessary to adjust well; the drawing start opportunity, drawing speed, pre-blowing start and completion opportunities, pre-blowing pressure, pre-blowing air flow, etc., if possible, can control the overall temperature of the preform. Temperature gradient on the inner and outer walls. During rapid blow molding and cooling, induced stresses are generated in the bottle wall. For inflatable beverage bottles, it can resist internal pressure and is beneficial, but for hot-filled bottles, it is necessary to ensure that it is fully released above the glass transition temperature.