PET mould,PET preform mould,PET bottle mould features
- cavity of PET mould varies from 1 to 96
- State-of-the-art construction is developed with consulting European style.
- Prolonged lifetime more than 2 million shots of injection cycle .
- Mould impression and Core insert are manufactured from steel brought from ASSAB or Germany(DIN 1.2316) featuring excellent polish feature, superior hardness( HRC46-HRC53) and anti-rust to acquire substantial accuracy and fantastic quality.
- Unique developed water hoses reduce leaking and cooling water-spots on preform.
- Moldflow analysisminimize AA degree.
- Global criterion screw neck, brought in nitriding steel with superior hardness and durable time.
- Patent developed correcting technique is implemented to reduce the potential preform thickness disorder occurring in the course of manufacturing.
- The pneumatically-driven nozzle pin(Japan Origin) for synchronized high-rate up and down motions.
- 26MM,PCO28MM,25/30MM,32MM,38MM,48MM,52MM,62MM, Standard PCO,neck finish
PET Mould Classifications:
- Pneumatically-driven valve,shut off nozzle
- Long relics
- Short relics
PET Mould design Layout:
1.Water Cooling Technique
Unique layout of water cooling Channels help to make the cycle time short . And each the water channels was in particularly processed to hinder them from jam;
2.Off-center Correction Technique
Off-center Correction Technique can make the difference of preform’s wall thickness less than 0.006cm. While this system does not affect the duration of PET mould life;
3.Self-locking Technique
Worldwide state-of-the-art bi-axls fixed alignment and self-locked arrangement was put into practice on our PET preform mould.
4.Hot Runner System
The PET preform mould undertakes Pin-valve sort of Hot Runner System Technique , this kind of hot runner system is effective in reducing part’s wear & tear degree and preservation cost, and also lower 10%~15% electric power;
5.Heating Technique
Dual Heating And Cooling can make certain that effects of heating and cooling are great and quality management is trustworthy. The Heating coil unit allows nozzles be kept with constant temperature. The Heater System is employed to heat the hot runner plate with long life and effective heating capability.Heating band inside our preform mould is “hotset” imported from Germany;
Preform mold spare parts and after-sale services:
we are a devoted PET mould,preform mould,PET bottle mould manufacturer and maker in huangyan,China.Each set of PET preform mould undergoes strict mould trials and preform mould trial video will be sent to customer for confirmation before shipping from factory and attaches full set of parameter that is recorded depending on their own and sole serial number. Together with the PET preform mould, full set of spare parts will be supplied for free to keep mold normal operation . In the use of the PET preform mold, Topworks provides adequate spare part to any request and Topworks service department are very willing to provide technical support immediately for any possible request in any time,also we could send our engineers overseas for mold installing and adjusting.
PET preform mould video
PET preform mould 发布人 stevencheng
4 cavities jar PET mould 发布人 stevencheng
PET preform mould with 8 cavities 发布人 stevencheng
PET preform molding troubleshooting
PET preform neck finish categories
| PET preform specification | |
| Necksize | Weight (for carbonated soft drink and mineralwater) |
| 26mm | 13g 16g 18g |
| PCO28mm | 11G 15G 17G 18G 20G 21G 24G 25G 26G 27G 28G 32G 35G 40G 43G 45G 48G 52G 56G |
| 25/30mm | 14G 15G 16G 18G 20G 23G 25G 32G 34G 38G 43G |
| 38mm | 28G 30G 35G 45G 48G 50G 60G 65G 68G 72G 87G |
| Necksize | Weight(for cooking oil) |
| 32mm | 20G 30G 35G 40G 47G 50G 55G 60G 70G 80G |
| 37mm | 48G 60G 65G 70G 73 G 85G |
| 46mm | 55G 60G 65G 70G 75G 80G 84G 90G 95G 100G 103G 105G 110G 115G 130G 140G |
| 72mm | 175G 140G 238G 255G 290G 300G |
PET injection moulding processing introduction
PET, also called poly ethylene terephthalate, is also known as polyester. At present, the most used kind is PET-GF; it is mainly for bottle PET preform manufacturing. The rheological property of PET is better in molten state, and the pressure effect on the viscosity is greater than that of temperature. Therefore, it is mainly to change the fluidity of the melt by changing the pressure.
- plastic processing .due to pet macromolecules containing grease, it is hydrophilic. Pellets in high temperature water are more sensitive, the much moisture will decrease the molecular weight of pet, which would lead to poor color and brittle parts. Before processing, the material must be dry; the drying temperature is 150 degrees, time more than 4 hours. And generally it is 170 degrees, about 3-4 hours. Whether the material is completely dry can be tested by shot to air. Recycled material ratio is generally not more than 25%, and also the reground material should be completely dry.
- injection moulding machine .due to the shorter stable time after melting and high melting point, it is necessary to use the injection machine with more multi-step temperature control and less plasticizing friction heat system .and all weight(products and runner) is not less than 2 / 3 of machine injection volume .
- PET preform mould and its gate design. Generally, PET bottle preform mould is installed with hot runner system. There should have insulation plates (about 12 mm thickness) between the PET preform mould and injection moulding machine, and the heat insulation plate can withstand high pressure. Air venting must be sufficient to avoid local overheating or fragmentation, but the depth of the slot is generally not more than 0.03 mm, otherwise it is easy to invite flash.
- melt temperature .it is 270-295 degrees Celsius by shot to air, PET-GF can be set to 290-315.
- injection speed. The fast shot can prevent premature injection solidification. But too fast will lead to high shear rate and the brittle products. Shot is usually completed within 4 seconds.
- back pressure. The possible low back pressure is a better way to avoid wear. Generally the back pressure is not more than 100 bar.
- stay time and temperature. Stay time shouldn’t be long to prevent the decline of molecular weight, and the temperature should avoid more than 300 degrees Celsius possibly.
If the down time is less than 15 minutes, shot to air is OK; but if over 15 minutes, it should use PE to clean barrel, and the barrel temperature decrease to PE temperature.
Note: recycled materials cannot be added much, otherwise it easy to produce poor quality products. If the mould temperature or material temperature is not proper, it is easy to produce “opaque” pet preform. The low mould temperature and the fast cooling rate would achieve transparent PET preform.
plastic preform moulding trouble shooting
| faults | causes | solutions |
|---|---|---|
| bottom whitening of PET preform | too low temperature of nozzle of hot runner too low temperature of plastic materia | improve the insulation increase the nozzle temperature increase the material temperature increase the injection speed lower the packing pressure lower down the cooling water speed |
| Opaque pet preform body | poor material drying insufficient material plasticizion too thick wall and poor cooling foreign material mixed too low material temperature | ensure 4+ hrs drying increase material temperature increase the rotation speed of screw verify the drying temperature and shot volume, drying temperature 165 ℃ and moisture<0.02% improve the cooling and make the wall thinner |
| Pet preform from transparency to Opaque | too high ejection temperature | improve cooling prelong the cooling time change injection time |
| haze on the one side of the preform | too high hold pressure eccentric gate | lower the hold pressure fix the PET preform mold |
| sliver streaking or yellowing of PET preform | plastic decomposition | lower drying temperature and prelong drying time change the injection speed lower the material temperature lower nozzle temperature |
| voids in Pet preform | insufficient drying | improve the drying increase the material temperature lower the rotation speed of the screw |
| uneven ring groove on the inner wall | vapor condensation in the core and cavity | improve the workshop drying increase the cooling water temperature drain the PET preform mold |
| breakage on the gate of the PET preform | misalignment of hotrunner nozzle and gate undercut on the gate gate too hot | fix the PET preform mold fix the gate prelong the cooling time increase the injection speed or prelong the injection time improve the insulation of the gate |
| short fill or welt line on the neck of PET preform | poor venting eccentric gate position | enlarge the venting groove clean the screw neck lower the injection speed fix the gate |
| uneven wall thickness of PET preform | poor quality of PET preform mold eccentric gate orifice too high injection pressure eccentric core | fix the PET preform mold increase the material temperature lower down the pressure improve the accuracy and use adjustable core and cavity |
| surface dent of the PET preform | too high material temperature too short injection time too short hold time too quick injection speed insufficient cooling | lower the material temperature prelong the injection time increase the hold pressure lower the injection speed increase the cooling water pressure |
| nozzle drooling | poor insulation insufficient cooling too much pressure on the melt poor non-return on screw head too low hold pressure | secure the gate insulation improve the cooling clean the screw increase the hold pressure |
| PET preform bend after ejection | eccentric gate orifice uneven cooling | fix the PET preform mold; lower hold pressure increase the injection speed; prelong the cooling time clean the cooling line; increase the cooling water pressure |
| PET preform bend after heating | eccentric core eccentric temperature adjust orifice uneven density of PET preform | fix the PET preform mold fix temperature adjust base lower the temperature,especially on the bend section. |
| PET preform local whitening | insufficient PET preform heating temperature | increase the PET preform heating temperature and even the all body temperature |
| insufficient expanding of PET preform | insufficient air pressure insufficient heating temperature injection fault of PET preform | increase the air pressure and air increase the temperature of the PET preform verify the PET preform even soften by 100 C water |
| crack of the preform bottom | too high preform bottom temperature too low preform temperature severe decomposition | adjust the preform temperature check and change the preform and material,improve the drying |
| PET preform eccentricity | too early blowing too high air pressure misalignment of blow pin the bottle bottom severe eccentricity too low speed of blow pin distance between blow pin and bottle bottom over 1.5 mm too high PET preform bottom temperature | delay the blowing time lower down the air pressure check and fix the installment check the PET preform adjust the air cylinder pressure adjust the distance between blow pin and bottle bottom to be 1.5mm or smaller lower the preform bottom heating temperature |
| preform body insufficient extending on the vertical direction | too high heating temperature local cold slug insufficient air pressure and air volume poor venting of blow mold too high blow mold temperature; too thin wall bottle insufficient vertical draw ratio | adjust the PET preform temperature increase the air pressure and air improve the blow mold venting; improve the blow mold cooling fix the blow mold increase the vertical draw ratio |
| bottle circumferential uneven wall thickness | PET preform eccentricity uneven heating temperature poor venting | fix the PET preform mold improve the heating appratus lower the problem section temperature improve the venting |
| protrusion on the bottom | low temperature of PET preform bottom | blow earlier and adjust the heating temperature |
| bottle local whitening | local insufficient heating temperature too much local draw ratio | increase the PET preform temperature check the design of PET preform |
| bottle poor vertical loading | uneven wall thickness too high PET preform heating poor bottle profile | make the wall thickness uniform try low temperature and high pressure molding improve the design of bottle |
| bottle ease of broken after falling | unsufficient draw of bottom of preform decomposition after over heating | improve the draw raio of preform bottom improve the material drying before pet preform injection molding lower the blowing temperature |
| Pitting and whitening on the bottle body | unclean air too much moisture | install the air filter dehumidification of compressed air |
| too soft bottle body | poor design too high blowing temperature | improve the design try low temperature and high pressure blowing |
| burning and odour smell after blowing | too high blowing temperature poor quality of compressed air poor quality of material | lower the blowing temperature fix the air compressor and filter use the good quality material |
| The water taste changed after filling | too much aldehyde content bad quality material | low temperature of injection and blowing check the aldehyde content and expel bad material |