PETpla.net Insider 04 / 2010

BOTTLING / FILLING 31 PET planet insider Vol. 11 No. 04/10 www.petpla.net emphasis of the bottles is different to most manufacturers’. Rather than light weight The need is for strength for the long journey from Tibet to the markets. The bottles also need the ability to withstand the changes in air pressure as they travel from the factory’s 4,600 metres elevation to sea level. Once they reach consumers’ hands, they have to feel comfortable and sub- stantial. The preforms, weighing 18g; 23.5g; 36.8g and 47.6g respectively, are produced in-house. From idea to inception The first Krones 24,000 bph blow- moulder/filler bloc, plus a Contiroll labeller, was delivered in 2006. The testing ground for 5100 was Tibet itself; having been proved in its local market, 5100 was launched into China. In 2007 and the second Krones filler bloc and an Autocol pressure-sensitive label applier followed in 2008. Also rated at 24,000bph, its installation allowed production to be doubled. A third line, made up of a complete 36,000bph Krones PET line, arrived in early 2009. The company is already looking to the future – the new Tibet Glacier produc- tion hall has room for a further three lines. Challenges of height The bottling plant’s elevation required a series of special measures in order to assure reliable bottle pro- duction, filling and labelling. The rat- ings of all the drives had to be at least 20% higher than standard. Since Tibet Glacier also sells the water down to sea level, the bottles have to withstand a pressure differential of about 0.4 bar. The PET containers are filled as closely as possible to the brim in order to prevent bottle deformation; liquid is less susceptible to compression and expansion than headspace air. Air consumption of Tibet Glacier’s stretch blow-moulding machine at high altitude is considerably more than normal. At sea level and stand- ard barometric pressure, consump- tion is 581m³/h; in Lhasa, at 4,600m elevation, it almost doubles, to 999m³/h. The high-performance compressors, sup- plied by Krones, were specified with 70% more capacity, while the Contiform cool- ers are 25% more powerful than the norm. Other machine configurations largely conformed to Krones’ normal standards. However, an unfore- seen issue arose with the touch-screen com- puter control panels. They are normally rated up to 3,500m elevation; the equip- ment for Tibet Glacier had to be specially tested and certified as suitable for the thin air of the Tibetan Plateau. Installation work high up in the mountains was an entirely new experi- ence for the Krones staff involved and a few were affected by altitude sickness. Additional service personnel ensured the installation schedule was achieved. Tibet Glacier now has produc- tion capacity of two million b/day, or 300,000t/a. Within the next five years, the company is aiming to be listed on the stock exchange and to increase production capacity to 400,000t/a. The strategy is to build up the company’s image within China and then to look to other markets. Tibet Glacier is meanwhile operating three lines from Krones. The air consumption for the stretch blow-moulding machine is almost twice as high as at sea level. SurShot™ | Monosorb™ | Mono-Layer Active & Passive