PET Preform Mould Meaning An Increase In Nozzle Requirements
Introduction of PET Preform Mould
1, the weight of the product: different weight of the product requirements of the hot runner is completely different.
2, plastic raw materials: different German plastic raw materials have different processing variables, and those processing variables will affect the choice of hot runner system.
3, mold: how much like the number of cavity? What is the distance of the nozzle? What kind of material is it processed? Etc. These are the mold elements associated with the optional hot runner system.
4, the cycle: a rapid production cycle means that the requirements of the nozzle to improve. For example, the nozzle to accurately transfer heat, but also to be durable.
5, gate: for the point of the gate, in order to maintain good heat balance in each molding cycle, the flow nozzle must have a melting material and cooling sealing function. While the valve gate is a mechanical way to seal the gate.
6, the nozzle: the nozzle can generally size, temperature distribution, physical properties, materials used (copper, steel, etc.) and the ease of maintenance and price distinction.
7, the flow channel: the use of hot runner system to avoid the production of material, which not only saves the raw materials, while eliminating the need for manual, robot or other means to remove the material to the process.
8, temperature control: each nozzle must be connected with a relatively complex temperature controller
9, the performance of injection molding machine: to install a given size of the mold,PET Preform Mould to provide adequate clamping force, according to the requirements of the cycle time to operate, plastic enough materials and so on
10, product design: In general,PET Preform Mould we all know that the product design is completed first, but the final shape is completed in the hot runner mold. In order to ensure that the end of the formation of a smooth product appearance, easy to mold, the product structure must be considered in the design of those factors.
Preforms and solutions
The bottle is yellow
Reasons: Resin thermal degradation or oxidative degradation, but not to carbonation point
1. Reduce the drying temperature, the maximum drying temperature of 175 ℃; 2. Confirm whether the raw material specifications meet the requirements; 3. Confirm drying parameters ranging from 160 ℃ (6h) ~ 175 ℃ (4h); 4. Reduce the melting temperature to 280 ℃ ± 10 5. Reduce the extrusion back pressure, large extrusion back pressure can make the liquid mixed evenly, too small will produce bubbles, the range of 15 ~ 20bar; 7. Confirm that the control Screw buffer is not too much, at least 25mm; 8. to confirm the thermocouple and its institutions are damaged.
1. Reduce the melting temperature to 280 ℃ ± 10 ℃; 2. To minimize% control, because% control without feedback; 3. Reduce the injection speed, the range control in the 10 ~ 12g / s / cavity; 4. Reduce the extrusion back pressure, Extrusion of the back pressure range in the range of 15 ~ 20bar; 5. Reduce the screw speed to reduce the shear force, but to be within the cycle; 6 to confirm whether the raw material specifications meet the requirements; 7. Check the head there are impurities,PET Preform Mould Then remove it; 8. Verify that the thermocouple and its organization are damaged.
1. Reduce the dew point or increase the drying temperature; 2. Make sure the drying parameters range from 160 ° C (6h) to 175 ° C (4 h); 3. Verify that the melting temperature is at 280 ° C ± 10 ° C; 4. Make sure that the melt does not exceed the extrusion screw If you exceed, you need to increase the extrusion temperature or increase the cycle time; 5. Improve the cooling temperature of the head (minimum 160 ℃) 6. Make sure the barrel is not blocked; 7. Increase the extrusion back pressure; 8. Increase the screw buffer,PET Preform Mould Buffer at least 25mm; 9. reduce the return time and location, time -1s, distance-10mm; 10. If the use of recycled materials, particles can not be too large; 11. Check whether there are impurities in the nose, ;
Inside the bottle slightly concave
1. Ensure that the cooling water temperature is between 7 ° C and 10 ° C; 2. Verify that the cooling water is flowing normally; 3. Ensure that the stem is open properly; 4. Ensure that the pressure is sufficient to open the valve with a pressure range of 8 to 10 bar; 5. Reduce the cooling time, Cooling time 1s ~ 3s, determined by the wall thickness; 6. increase the holding time; 7. increase the packing pressure; 8. increase the melting temperature to 280 ℃ ± 10 ℃; 9. reduce the return time and location, time ,PET Preform Mould The distance -10mm; 10. Make sure that the mold tooth mouth part of the clean, you can make the exhaust smooth; 11. Ensure that there is no condensate, dew point than the cooling water temperature is low;