PETpla.net Insider 05 / 2021

BOTTLE MAKING 24 PETplanet Insider Vol. 22 No. 05/21 www.petpla.net Air Master technology in stretch-blow moulding systems Reusing air The production process of PET and rPET containers by means of stretch-blow moulding systems requires the use of high pressure compressed air produced by a compres- sor powered by electricity. SMI stretch-blow moulders are designed to ensure energy efficiency; in particular, the machines of the latest generation using the technology of the Air Master double stage air recovery system, that ena- bles compressed air consumption to be reduced by up to 40% compared to the systems that are not equipped with it. GAWiS D featuring AutoJob ™ – job set up in seconds +1.724.482.2163 AGRINTL.COM ACCURATE • FAST • REPEATABLE SEE GAWIS4D IN ACTION Dimensional and thickness measurements for plastic containers and preforms. ® Air Master: what it is The double stage air recovery system is configured as follows: the first stage recovers the air that is then used for the pre-blowing and the machine service phases. The second system, that complements the first one, takes part of the exhaust air and uses it exclusively for the blowing phase. Air Master: how it works On every stretch-blow mould- ing station, two exhaust valves are installed: the first feeds the recovery system, pumping air into the recovery line, while the second discharges the air that cannot be recovered. The air recovered is taken and used for feed- ing the pre-blowing and the machine service circuits. Some extra air is used for feeding the low pressure line of the machine external utilities. The second stage allows a further saving, as it uses the exhaust air for the blowing phase. SMI stretch-blow moulders of the previous generations can benefit from the advantages of this recovery system, by installing an upgrade package. Air Master upgrade The upgrade ensures recovering the compressed air that would other- wise be released to the environment. By reusing the air of the stretch-blow moulding process the reduction of high pressure air and electricity con- sumption of up to 30% results in an eco-sustainable production process. As a positive side effect, there is less wear and reduced maintenance costs of the compressor. An example of calculation: sav- ings can be achieved by installing the Air Master upgrade on a stretch-blow moulder with 8 cavities, producing 1.5 l PET bottles at 2,250 bph, with a blowing pressure of 33 bar and a pro- duction of 4,000 h/a. With an upgrade, 30% air savings can be achieved, the consumption is about 784Nm 3 /h, resulting in energy costs at 43,903 € per year. Without the upgrade the air consumption is about 1,120Nm 3 /h with energy costs at 62,720 € per year. www.smigroup.it