The injection stretch blow moulding process is divided into 4 stages: injection, stretching, blow molding and removal. After melting the plastic is injected into the mold into a preform, and then adjust the preform to the appropriate temperature can be stretched and blown, forming the final shape. When the preform is in the mold, an extension rod is stretched into it, the preform is drawn lengthwise, and the two-stage air pressure is blown in the circumferential direction.
After a certain period of cooling, open the mold, using the blanking chute or manipulator to remove the preform, and then repeat the process.
New advanced machines ensure high flexibility, high productivity and quality With the development of single-stage injection stretch blow molding machine Blowliner, Kiefel company subsidiary Mold&matic opened up a new market.
The machine is now used in the pharmaceutical and food industries. Blowliner has three kinds of specifications, the most popular is the material processing capacity of the largest 130kg pet per hour Blowliner Medium, with smaller and larger models, can also be processed PET, pp and HDPE.
Thanks to the intelligent concept of the machine, it can be upgraded at any time for the production of multilayer products.
Most importantly, the high-end industry, which attaches great importance to packaging quality and transparency, values level 1 systems. Engelli Hydraulic machine clamping force up to 4000kN, clamping area of up to X 1000mm, the specific data depending on the specifications of the system.
The plasticizing unit can process pet, pp and HDPE, depending on the product there are 8 to 64 cavities. Each machine can be upgraded to produce multi-layer preforms. This allows the production of preforms made from PP and barrier layer Evoh or preforms made from pet and Pa.
A linear manipulator with a gripping mandrel removes the preform at high temperature and places it in a stretch blow unit with a clamping force of up to 400kN. The machine uses one to four rows of blow moulding molds and can process preforms from 10 to 150mm in diameter.
Each series of cavities have their own pre-blow valve and main blow valve, can set the pre-blow and the main blow pressure separately, thus can be in a mold to produce different styles of products. The entire stretch blow moulding unit is equipped with a servo motor driver for maximum reproducibility, accuracy and energy efficiency. Using the valve technology can be in 0.1bar increments, set the pre-blow molding pressure and the main blow molding pressure.
In the verification process, according to customer demand blow molding research to determine the appropriate material distribution in the blow mold. Another option is that the process monitoring system can use a pressure sensor to measure the main blow molding pressure during the main blow valve operation. If the pressure drops suddenly, the manufacturer of the plastic product will immediately receive the alarm information.
If requested, the Blowliner can be used as a spray blow moulding machine without stretching components.
At the end of the blow molding process, the vacuum gripper with the integrated linear extraction system takes the finished product out of the mold and places it precisely on the conveyor belt or directly in the box. In the Blowliner design phase, the company considered many aspects of mold technology.
The solution is a balanced hot runner mold with pin locking system.
With a cycle time of 10 seconds and a small blowliner s cycle time of less than 8 seconds, the Blowliner m provides the market with an injection stretch blow moulding technology that delivers superior product quality, flexibility and productivity.
Vacuum drying technology to assist pilot production and small batch production
Compared to desiccant dryers, the LPD vacuum dryer from the Kai (Maguire) significantly shortens the time required for start-up and conversion, not only to reduce energy usage, but also to increase efficiency and uniformity.
As a company specializing in the injection stretch blow molding business of PET bottles, R&d/leverage has been reducing the time to solve multiple problems, especially drying polymers, by turning from desiccant dryers to vacuum dryers. According to general manager Alan Tolley, R&d/leverage's seven Nissei ASB and Aoki injection stretch blow molding line was originally used as a desiccant dryer, saving a lot of time after changing the Chengmi company's LPD vacuum dryer.
The LPD dryer is only 1 hours and 20 minutes from cold start, and is shortened to 40 minutes during the subsequent drying cycle. As the LPD vacuum dryer is able to dry materials more quickly and efficiently than desiccant dryers, less stress is applied to materials and shorter heating times. According to Paul Edmondson, general manager of Kai Europe, "because the drying process of polymers may account for up to 15% of energy consumption in the injection molding business as a whole, a strong reason for using a vacuum dryer is that its energy consumption is 80% per cent lower than that of dehumidification systems. This example of R&d/leverage proves that the speed and quality of vacuum drying technology can make tool manufacturers and laboratories significantly more productive in terms of productivity, and that processors can also enjoy the benefits of this technology over dehumidification systems in full production. People always need to save energy and improve production efficiency, vacuum drying technology may become the leading technology in the field of polymer drying.