In fact, both PET preforms and preforms are plastic products. All products have their own characteristics and some disadvantages. Only high-quality materials can be used to produce high-quality products. Let's take a concrete look at the preform.
The production of preforms is obviously more difficult than forming large bottles. Because the main purpose of preforms is currently test products, the quality of preforms directly affects the success rate of the test. At the same time, the ability to manufacture high-quality preforms is also a manifestation of the company's strength.
The preform is the prototype of the PET bottle before it is formed. Its tube wall is thick and transparent, and it can be sealed with a general plastic bottle cap. With the advantages of being unbreakable and standing on the table, it can be used to replace test tubes. use.
The preform is generally formed by a hot runner mold. It is better to have a heat shield between the mold and the injection molding machine template, the thickness of which is about 12mm, and the heat shield must be able to withstand high pressure. Exhaust must be sufficient to avoid local overheating or chipping, but the depth of the exhaust port should generally not exceed 0.03mm, otherwise it is easy to produce flash.
The quality of the bottle depends on the quality of the preforms supplied. There are two types of preforms during injection molding, one is a long gate and the other is a short gate. Domestic preform manufacturers use short gate preforms more, while foreign preform manufacturers choose long gate preforms.
The preform with a long plastic mouth is cut off due to the gate at the bottom, so that the tension is evenly distributed during the blowing process, so that the quality of the blown bottle will be better, and the cut part can be recycled, which is beneficial to save the cost of raw materials. In today's increasingly scarce oil resources, domestic manufacturers will be more inclined to preforms with long gates. The quality control of the preform in the production process depends on the degree of control to avoid the preform from being scratched during the conveying process.