Key Technologies for PET Preform Injection Molding The chemical name of PET is polyethylene terephthalate, also known as polyester. At present, GF-PET is the most used by customers, mainly for bottle preforms. PET has better rheology in the molten state, and the pressure has a greater effect on viscosity than temperature. Therefore, We mostly adjust the injection pressure to change the fluidity of the melted PET material. 1. Processing of PET Material before Injection Molding Because PET macromolecules contain fat bases and have certain hydrophilicity, pellets are more sensitive to water at high temperatures. When the moisture content exceeds the limit, the molecular weight of PET decreases during processing, and the product becomes colored and brittle. Because of this, the materials must be dried before processing. The drying temperature is 150°C for more than 4 hours, generally 170°C for 3-4 hours. The air shot method can be used to check whether the material is completely dry. The proportion of recycled materials should generally not exceed 20%, and the recycled materials must be thoroughly dried. 2. How to Selection a Right
Read more →Key Technologies for PET Preform Injection Molding The chemical name of PET is polyethylene terephthalate, also known as polyester. At present, GF-PET is the most used by customers, mainly for bottle preforms. PET has better rheology in the molten state, and the pressure has a greater effect on viscosity than temperature. Therefore, We mostly adjust the injection pressure to change the fluidity of the melted PET material. 1. Processing of PET Material before Injection Molding Because PET macromolecules contain fat bases and have certain hydrophilicity, pellets are more sensitive to water at high temperatures. When the moisture content exceeds the limit, the molecular weight of PET decreases during processing, and the product becomes colored and brittle. Because of this, the materials must be dried before processing. The drying temperature is 150°C for more than 4 hours, generally 170°C for 3-4 hours. The air shot method can be used to check whether the material is completely dry. The proportion of recycled materials should generally not exceed 20%, and the recycled materials must be thoroughly dried. 2. How to Selection a Right
Read more →The PET preforms most used of PCO neck finish ( PCO = Plastic Closure Only ) are two types: PCO 1881 neck finish and PCO 1810 bottle neck finish. At the beginning of November 2006, the ISBT (International Society of Beverage Technologists) agreed on a new lightweight standard for 28mm preform neck finish called PCO 1881, which provides a weight saving of 1,3 g (26%) compared to current type bottle neck PCO 28 (3.74 g vs. 5.05 g) and of 2,5 g (40%) compared to BPF neck finish. In particular, it includes good venting capability due to sufficient thread length (650° thread travel, extendable to 680°) and adequate positioning of vertical slots across the threads; and efficient closure tamper-evident (TE) band functioning due to special TE bead profile. The SuperShorty PCO 1881 bottle neck is a 28-mm closure designed for a short-height PET preform neck finish. The biggest difference between PCO 1881 & PCO 1810 is the height of them. PCO 1881 is the with the height 17mm while PCO 1810 has 21mm. The neck finish PCO 1881 is about
Read more →It is very important for PET preform Mould Lubrication System which have sufficient stiffness and strength. There are many factors should take care for a mold maker when starting a PET perform mould designs. The lubrication system of the mold plays a vital role in the PET preforms mould quality. It is the key in the PET preforms forming process. The material used for PET performs mould should be strictly select with considering their characteristic. Each part should be helpful for the mold gliding property, stability, accuracy, stiffness and strength, etc. There are two major categories for a mold making materials: metal and metal materials. The metal materials is mostly includes different no. of steel, aluminum alloy, etc. And the non-metallic materials are mainly have gypsum, cement, FRP, wood and so on. No matter what materials is used, but the preform mold must meet below requirements: 1. Reach the PET performs` accuracy of size. This is the basic rule you should keep in mind during the whole process of a PET preform mould design. 2. Make sure the mold have
Read more →PET injection molding process is one of the very important technology for plastic processing.This blog systematically introduces PET processing by plastic injection molding machines. The content includes PET property, features, injection molding process, molding machines, process conditions, processing ways,etc. It will help PET making factory get useful knowledge in few minutes. PET plastic injection molding process is one of the very important technology for processing plastic, PET plastic bottles, most of the plastic packaging plant will adopt blow molding production process, but the injection molding process has especially the unique processing advantages. For PET for injection molding, technical personnel need to consider many factors. PET plastics introduction PET chemical name is Polyterephthalate alcohol ester, also known as polyester. At present, the most used by customers is the GF-PET, mainly for the bottle preform. The rheological property of PET is better in the melting state, and the influence of pressure on the viscosity is larger than that of the temperature. Therefore, the property of flow of melted material is changed mainly from the pressure. PET features & property: The glass conversion
Read more →We spend more than two weeks to edit this PET preform troubleshooting guide for PET injection Molding. As many customers asking us a lot for PET preforms defects and remedies again and again. Now it`s public for reading and hope this article can help our customers and friends and save both our times. Please feel free to contact us or leave your comment after the article if your issue is not list in below table. We will check and find out the solution for you. And update this table to help most people to fix the problems. If the information can`t solve your problem or any issue on PET preform troubleshooting, please leave us a comment for we can check and update the solution for your information. Feel Free to Contact Us if Any Questions
Read more →In order to understand the PET bottle neck finish dimensions & PET bottle neck types, we need to know a number of things before talking the details. PET Bottle Neck Definition and Measurements The neck of the bottle is defined by its total height, its inner diameter, its outer diameter and its thread. The dimensions of a neck (expressed in mm). PET Bottle Neck Finish Dimensions Measurements “T” Dimension – The outside diameter of the thread. The tolerance range of the “T” dimension will determine the mate between bottle and closure. “E” Dimension – The outside diameter of the neck. The difference between the “E” and “T” dimensions divided by two determines the thread depth. “I” Dimension – The inner diameter of the bottle neck. Specifications require a minimum “I” to allow sufficient clearance for filling tubes. Linerless closures, with a plug or land seal, and dispensing plugs and fitments require a controlled “I” dimension for a proper fit. “S” Dimension – Measured from the top of the finish to the top edge of the first thread. The “S” dimension
Read more →Plastic PET Preform Injection Molding Troubleshooting PET preform injection molding troubleshooting is very important during the whole PET bottles making process. As the PET preforms`s quality affects a lot in the following step PET preform blowing process. It may cause failed to bottle blowing if there are pet preform defects like the moisture not match the requirement(PET heating temperature is not collect). And will will waste lots of raw material if the preforms getting yellow (over melted or burned ). Below table list is the PET preform injection molding troubleshooting guide for your further information: Above PET preform injection molding defects and remedies are base on our experience in the last 16 years. Please feel free to contact us or leave a comment below if you had meet any other problems we don`t listed. We will try our best the work out a solution once we saw your message. Feel Free to Contact Us if Any Questions
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