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Working principle and process flow of bottle blowing machine

Currently, most bottleblowing machines on the market are two-step linear fully automatic bottleblowing machines, which simply means that the production process of a mineral water bottle is formed by stretching and blowing the preform crystallized from plastic particles through the mineral water bottle. The specific working principle and industrial process of the bottleblowing machine are as follows:
Bottle blowing machine is a kind of equipment that is frequently used in the market today. Its simple operation is to stretch and blow bottles made of crystallized plastic through a bottle blowing machine. I'm sure everyone is curious about its detailed operating principles, so next, I will introduce the working principles and process flow of the equipment.
1、 Working principle of bottle blowing machine
The bottle blowing process of the bottle blowing machine is divided into two parts
1. Preheating
The bottle preform (embryo) is illuminated by an infrared high-temperature lamp, and the damaged (embryo) body of the bottle preform (embryo) is heated to soften. In order to maintain the shape of the bottle mouth, the bottle preform (embryo) mouth does not require heating, so a certain cooling device is required to cool it.
2. Bottle blowing machine blow molding
During this period, the preform (embryo) that has been preheated is placed into the already prepared blow mold, and high-pressure inflation is conducted inside it. Blow and pull the preform (embryo) into the desired bottle.
The fully automatic bottle blowing machine for mineral water bottles combines the two operations of bottle blowing through the operation of a manipulator, eliminating the process of manually putting the preheated bottle preform into the mold by the center. The production rate has been greatly accelerated.
2、 Process flow of bottle blowing machine
The blowing process of a bottle blowing machine is a biaxial stretching process, in which the PET chain is biaxially extended, oriented, and placed, thereby increasing the mechanical properties of the bottle wall, improving the tensile, tensile, and impact strength, and having good air tightness. Although stretching can help improve strength, it is also important not to overstretch. The stretching blow ratio should be controlled well: do not exceed 3.5 to 4.2 in the radial direction, and do not exceed 2.8 to 3.1 in the axial direction. The wall thickness of the preform should not exceed 4.5mm.
Bottle blowing is performed between the glass transition temperature and the crystallization temperature, usually controlled between 90 and 120 degrees. In this region, PET exhibits a high elastic state, and after rapid blow molding and cooling, it becomes a clear bottle.
In the process of blow molding, there are three actions: stretching, primary blow, and secondary blow. The three actions are very short in duration, but they must be well coordinated. Especially, the first two steps determine the overall dispersion of the bottle material and the quality of the blow bottle. Therefore, it is necessary to adjust the following conditions: stretching start opportunity, stretching speed, pre blowing start and end opportunity, pre blowing pressure, pre blowing flow rate, etc., and be able to control the overall temperature dispersion of the preform and the temperature gradient of the inner and outer walls of the preform.
Summary: Bottle preforms are transported from the automatic feeding machine to the main machine of the bottle blowing machine through a conveyor belt to the oven, preheated, and transported to the mold closing device. They are stretched through a stretching rod, pre blown, and blown into bottles at one time by high-pressure blowing. The entire process requires no manual intervention, and is completely completed by the bottle blowing machine equipment, with high automation efficiency, saving labor and production costs, and improving comprehensive economic benefits.
The above is the working principle and process flow of the bottle blowing machine. Through understanding these aspects of knowledge, we can understand its equipment, understand the purpose and requirements of operation, and provide convenience for our subsequent operation and use.