Even if uniform equipment to produce uniform specifications of the bottle, because the PET data function differences, the required pre-blowing pressure is not the same. Glass fiber reinforced PET data, the smaller pre-blowing pressure can make the bottom of the bottle of macromolecules accurate orientation; other materials used inappropriate or forming process is not appropriate preform, pouring around a large number of stress concentration is not easy to subside, If blow molding, often at the point of the break or in the stress test from the point of burst, leakage. According to the premise of orientation, this time as shown in the lamp out of 2-3 to the point above the opening, given the point of adequate heating, supply enough heat to promote its agile orientation. For preforms that have been heated for secondary applications or preformed preforms, the difference between the two temperatures is similar to that of the normal preform, and the requested heat is less and the pre-blowing pressure can also be reduced The 2.4 auxiliary equipment and mold auxiliary machine mainly refers to the mold to maintain the temperature of the equipment. Mold temperature has a major effect on maintaining the stability of the product.
General bottle temperature is high, the bottom of the bottle temperature is low. For the cold bottle, because the bottom of the cooling effect of the resolution of the molecular orientation of the level, the temperature control at 5-8 ℃ is better; and the bottom of the hot bottle temperature is much higher. Mold is the main function of the PET bottle blow molding process, the mold shape of the black and white will reduce or increase the difficulty of the process of adjustment, such as reinforcement, the arc of the transition zone and the bottom of the cooling state and so on have an impact on the swap process. 2.5 situation of the production of black and white on the process also have a greater impact on the transfer, a constant premise can keep the stability of the product and product stability. PET bottle blow molding is generally at room temperature, low humidity is better. 3 other requests for pressure bottles should also meet the requirements of stress testing and pressure testing. Stress test is to prevent the PET bottle filling the bottle and the lubricant (alkaline) in the process of molecular chain degradation occurred in the cracking, leakage and other content of the quality control; pressure test is to prevent the bottle charge Into the inevitable pressure after the body burst and the quality of the control. In order to meet these two needs, the central point of the thickness to be held in a certain range, the general situation is the center of thin, stress test is better, poor pressure; center point thick, good pressure test, stress test is poor. Of course, the results of the stress test also with the center of the transition area around the accumulation of material has a great relationship, which should be based on practical experience to adjust. 4 Conclusion PET bottle blow molding process is adjusted for the response to the information carried out, if the information is not safe, the request for the process is very harsh, and even difficult to blow the finished bottle.
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