NEWS
28/04/2020

Small is beautiful

The COVID-19 emergency is changing the way we live. As we come out the other side, some things will go back to how they were, some things won’t. Hopefully, we will learn from the experience, and will be better prepared for the future. One of the things we understand more than ever is the importance of personal hygiene. High on the list of our “to do” lists today is “Wash your hands.” That message is likely to stay with us through the days when we can look back on this time.


Soap and water is best, but when we get out and about again, maybe we’ll want to have a small liquid hand sanitizer about our person to do the job. Demand is likely to increase for small bottles that fit in the pocket or a handbag. SIPA expects that the popularity of its ECS SP single-stage injection-stretch-blow molding (ISBM) units will increase further in the coming months, as converters invest in equipment to cater for increased demand for small PET bottles that can be fitted with spray or dosing units for sanitizing liquids. These compact and highly flexible machines can also be used for production of small bottles for pharmaceuticals, which may well also be needed in increased quantities, as well as other non-food and food products.


SIPA’s expertise in ISBM systems stretches back over more than 30 years. The company offers “ECS” equipment capable of making anything from miniature bottles through to large containers holding as much as seven liters. Customers like them because the costs associated with several elements of two-step processes (preform handling, preform storage, preform cooling and reheating) disappear. There are two models of four-station (injection, conditioning, blowing, discharge) ECS SP units dedicated to small containers, the ECS SP80 and its smaller sibling, the ECS SP25 (the numbers refer to injection clamp force in tonnes). Both are ideal for production of containers as small as 10 mL. Large tie-bar spacing also enables production of containers up to 12.5 L in volume (on the ECS SP80).


ECS SP machines have special design features that make change-overs between different product configurations quick and simple. In addition, they all take up little floor space and are very energy-efficient. ECS SP machines also handle preforms in a way that makes it possible to mold neck and shoulder designs not feasible with two-step technology. Integrated production of preforms and bottles ensures scratches-free surfaces on the finished products.


These models use hybrid drives: hydraulics where large forces are required (to apply clamp force during preform production, for example) and servo-electrics for fast, precise and energy-efficient movements (opening and closing of the blowing unit, plasticizing screw rotation, index rotation). This combination helps the machines achieve a carbon footprint smaller than rivals.


Blow air pressure of up to 40 bar can be used to produce very sophisticated and complex bottle shapes. The ECS SP80 and SP25 can produce hot-fillable PET containers that withstand filling temperatures up to 90°C. Innovative features such as adjustable strokes for injection and stretch-blowing according to preform length and bottle diameter are useful for optimizing cycle time and energy consumption.


A short while ago, the operators interface (HMI) of the ECS SP units underwent a significant redesign in the wake of numerous consultations with machine operators. The company analyzed the various procedures that the operator needed to go through to set up the machine and created a set of shortcuts to simplify those procedures. The result is a highly intuitive interface that makes it possible for the operator to get to where they want to be, and do what they need to do, with a minimal sequence of gestures.


Preform conditioning is very energy-efficient. Individual cavities can be provided with their own conditioning parameters, determined according to the design of the preform. In the bottle blowing section, it is also possible to manage conditions in each cavity separately, so that every bottle is of the highest quality.


Hot runners in the preform injection section of ECS SP machines use needle valve gates. These can be purged very quickly, so the time taken to get a machine up and running is short. The simple geometry of the gates enables a simple solution for clearing the hot runner system. The hot runner system can feed up to 10 cavities.


Both machines feature a quick change-over between different mold configurations. Ideally, they operate with molds made by SIPA, but an adaption kit makes it possible for them to run with molds from other OEMs. A quick mold change system is important because production runs for small containers can be quite short. The system involves an automated procedure for loading and unloading the preform core plate; this incorporates additional sensors to ensure that the mold opening stroke adjusted correctly according to the preform length. SIPA has also developed a system for assembling and disassembling the neck ring plate so that procedure can be safely carried out by one person. Changing the blow molds is easy too.


Other important features of the ECS SP 25 and ECS SP 80 include: a best-in-class lock-to-lock time; a very competitive investment/output ratio and hence bottle cost; higher cavitation capability than rival machines of a similar size (at least 25% higher for the same size of container); ceramic heaters for faster heating and excellent material distribution for oval shaped bottles – without having to rely on costly and complex shaped injection tools; superior mold quality based on over 30 years of experience in single stage mold production at SIPA; and a very robust construction and very smooth operation for durability and repeatability.


In summary, the ECS SP family is ideal for use by converters wanting containers with high-quality appearance and non-standard necks, in limited production batches and in various colors – the sorts of requirements frequently found not only in personal care and pharma, but also cosmetics, food, liquor, and miniatures businesses.