Six Krones bottling lines
All of the fresh milk in Aylesbury plant are packaged on the Krones’ lines exclusively in HDPE containers. These bottles are produced in a separate building next to the bottling lines. Arla has outsourced the HDPE container production to the company Alpla, which operates on site as a converter, and delivers the containers via a vacuum conveyor to a dedicated point upstream of the filler.
The six similar filling lines went in operation in May 2014. Theoretically each line can handle up to four different bottle sizes. But in order to shorten the change-over times and upgrade efficiency levels, each of the lines specialises in two or at most three bottle sizes. Line speeds range from 12,000 containers per hour for the six-pint size to 24,500 containers per hour for the 250 ml bottle.
Each filling line begins by accepting the containers from the empty bottle conveyor into a Topmodul labelling machine, which is equipped with two Contiroll reel-fed label stations. “The wrap-around labelling is the most cost effective. The quick-change stations and the modular labeller design operate very efficiently,” is the verdict of Ian Packer, who as Project Manager at Arla Foods UK was responsible for installation and commissioning of all the machinery involved.
The filler selected in each case was enhanced design of the Krones Modulfill NWJ, an upgraded design to the Sensometic VP-GW generation of weigh filler for milk jointly conceived with Arla several years ago by Krones. This Modullfill, in hygienic design, has up to 64 filling valves, each of them fitted with a weigh cell.
Inspection system with over 20 functions
While still in the cleanroom, the filled bottles are capped with a screw closure fitted with an inductive bottle seal. The closures are fed in from a Capcade closure sorter, installed on the cleanroom’s roof. A camera verifies the colour of the closure, which will differ according to the product and the container size concerned.
Downstream of the capper, the containers are inspected outside the cleanroom by a Checkmat. “Quite an intricate piece of kit!” says an enthusiastic Ian Packer. “The Checkmat handles all the inspection functions required for container filling and labelling.” It performs more than twenty different inspection functions, including the presence and the correct placement of the labels, the fill level accuracy, the correct colour and the integrity of the closure application in addition to the presence of the aluminium seal. And there’s a new feature for detecting the print quality of the date-code imprint.
After being filled on the Krones lines, the containers then proceed to packaging machines, which place the bottles automatically into trolleys. One of these trolleys will accommodate four layers of 20 two-litre bottles each. This trolley system for delivering milk to point of sale is a family established concept in the UK retail industry. The trolleys are simply pushed from the delivery truck into the retailers’ outlet, and the consumer selects the product required directly from the appropriate point. Once a trolley is empty, it is folded away and returned for the next delivery.
End-of-the-line packaging and pallet stacking
In addition to the retail sector, Arla also supplies milk to all branches of a major fast food chain. These deliveries are made on traditional pallets rather than trolleys. Arla has therefore installed a Variopac Pro FS shrink packer and Variopac Pro WS wrap-around packer in another area of the bottling hall, enabling up to 40,000 packs a day to be produced.
“Krones is one of the most professional companies in this business, with a huge amount of experience and a vast wealth of technical expertise,” says Ian Packer, who for more than 30 years now has been commissioning plants in the food and beverage industries all over the world. Within just eleven months production capacity was ramped up from zero to over 500 million litres per annum. It was an excellent project. Without a doubt, I would opt for Krones as our vendor again in the future.”