Tim Brown talks to PET plastic bottle specialist Constar about the realisation of plastic beer and wine packaging.
The provision of a full service offering from conception to delivery is an operational principle at Constar. The company strives to satisfy the requirements of any new packaging project so as to be able to design, develop and manufacture not only the container, but also the lid. In essence, it might be said that Constar provides the complete package. This onestop- shop approach provides the company with a distinct advantage over many other specialist operators, and has played a significant part in the company’s success.
The benefit of plastic Polyethylene terephthalate (PET) is a thermoplastic polymer resin used in beverage, food and other liquid containers.
Phelan considers the company’s biggest strength to be the unique developments it has made with regards to PET and the creation of its patented products. He says that the Constar packaging materials are as good, if not better, than any competing substances including glass and feature a host of impressive added benefits. “We have a neat barrier technology known as oxygen scavenging,” says Phelan.
“First and foremost, if a product is oxygen sensitive, such as might be the case with orange juice, tomato sauce, alcoholic beverages or soft drinks, the product will be protected.
“We can produce a PET half litre beer bottle with a nine month shelf life, which means that it is as good as glass,” he says. “The difference is it weighs 29g whereas the equivalent glass bottle weighs 120g and PT costs about 20% less cost to produce.
The other benefits are: it is easy to recycle; it is lighter weight, so there is a transport benefit; and if it is dropped, it bounces and therefore it can’t hurt anyone. On top of that, our clients say it says it provides them with far greater design freedom. If a company wants a new PT pack, it only cost £2,000 to create a new mould, and it can include any required design or embossing. A glass mould will only be created for large orders of several million units due to the cost involved.” The company produces containers for a vast range of products, primarily in the food and beverage market, but has also began expanding in to the home hygiene market developing packaging for health, beauty and house-hold products. Constar is a world leader in the design and production of PET bottles for soft drinks and waters, and counts Coca- Cola amongst its list of customers.
Alcohol adoption Alcoholic beverage packaging is an area that is developing in strength for Constar, and one which Phelan believes will be a consistently growing market. At present the Leeds site produces packaging for both beer and wine, and plans are in the pipeline for development in to the spirit market.
“Within the wine market,” he says, “we have worked with companies including Wolf Blass and Jacob’s Creek. Plastic packaging in the wine industry is gathering pace at a rate of knots and the benefits for the wine industry are even greater due to the transport distances being even larger.” A 750ml glass wine bottle weighs over 450g while a PET bottle is 50g.
The PET bottle has over a two year shelf life and, importantly for wine drinkers, has glass-like clarity. “I think the use of plastic for wine packaging is going to have a five year rollout period, but it will eventually take over from a cost driven perspective. It is my belief that the cost competitive nature of the wine industry will dictate a move to PET.” The use of plastic for packaging beer is also on the increase according to Phelan, with the company already providing plastic bottles to Calsberg, Stella Atois, Peroni and Carling. This year Constar will produce 60m PET beer bottles, largely for use at outdoor events and festivals. “If you think about the population of the UK, that’s a lot of beer in plastic bottles,” he says.
The production process Product development moves through three distinct stages: design, prototyping and production. The design stage initially involves the company’s the development of the concept. This is then analysed by the product engineers and designers to test its feasibility. Phelan says there is a need for compromise between the two to ensure quality in design and functionality. The conceived product is then fully realised using 3D CAD software.
The company utilises a rapid prototyping suite for the creation of a tangible model which will then be analysed to ensure it will perform. Any necessary design changes are performed and the customer signs off on the finished model. Before any metal moulds are cut, therefore, the company is able to demonstrate the complete product and ensure it will complete its required task.
After the completed design has been approved, a pilot preform and pilot blow mould are created within three weeks, at which point the customer can then view their PET sample package.
Technology and development In order to produce approximately 500,000 bottles, 6.5 million preforms and 8 million closures on a daily basis, the Constar UK plant has embraced a number of important technological advances. “Because we do lots of small volumes, we needed to get away from the old style of working,” says Phelan. “To assist us to make our bottle production more efficient, we invested in a robotic cell which is all about having a quick change over and therefore being fast to market. With regards to preforms, we have developed a preform inspection system. Every preform that we manufacture is inspected. The inspection system runs automatically and allows us to move to a lights out operation. With closures, we’ve moved to a one-piece flow for closures which means we manufacture, print and pack in line. All of the three billion closures that we make also go through an automated visual inspection system.” All the Constar presses are run using statistical process controls (SPC) parameters to ensure uniform operation. If a machine steps outside the SPC, the process is stopped and the problem is investigated. No operation is performed outside of the SPC parameters and this is always maintained despite the continuity of the plants 24 hours a day, 7 days a week operational structure.
The company has also invested in the use of laser guided vehicles (LGVs) rather than electric or gas forklift trucks. This is due to the company’s realisation that LGVs run longer and are treated much more carefully than a standard forklift truck. An LGV uses triangulation to know its exact location and can be programmed to go to any location within the site, pick products up and deliver it to a set location. “Previously there would have been human operated forklifts manoeuvring about a factory causing untold damage to both themselves, to the plant and equipment and to the environment,” says Phelan. “LGVs are now quite common in the packaging sector due to having quite a low price difference when compared to a standard forklift.” In addition, Phelan says the company is hoping to commence a new project involving the installation of a gas-turbine engine to assist it with generating a large portion of its own power.
“We are currently trying to get some grants from the local government to give us the cash to help us purchase the gas turbine which will be used for generating electricity. Such a turbine would allow us to generate over 40% of the electricity needs for this site. Once we generate the electricity, there are two by-products. One of which is steam and water vapour will be used in the chill plant. The hot air that is generated will be used to help dry the PET. We’ve done one small pilot plant using that technique which has been very successful and we now want to expand that for the entire plant.” Technological improvements are not the only development steps made by Constar. The company has undertaken what it terms a ‘lean sigma’ universal training program, with every shop floor employee having undergone a green belt training course. Furthermore, every manager has gone through black belt training and a select group of quality technicians and some department managers have undergone a master black belt training course. As well as training, the company has spent considerable effort investigating ways in which it can limit its environmental impact, which includes the use of 25% recycled materials and a constant focus on energy efficiency and waste reduction.
Looking on a supermarket shelf today it is easy to see the inroads that the PET plastic packaging market has already made. Constar is looking to make even further advances in the uptake of PET in a range of different product markets.
Moreover, the company is not only looking to further establish its domestic market, but is likely to be looking further afield to develop its share in other less established markets.