Walkers Crisps Production Line, United Kingdom

Walkers Crisps is a UK brand with a 47% share of the British crisp market. The company is owned by PepsiCo Inc, (which also owns the US crisp producer Frito-Lay) and has sales of $85bn per year. The company's main product is ‘flat crisps'. The company's factories are highly automated with minimum human intervention.

The Walkers site in Leicester, England, is arguably one of the largest crisp production plants in the world, producing over 11 million bags of crisps per day and using about 800t of potatoes (280,000t per year).

The site's Leycroft Road plant produces classic flat Walkers crisps while the Bursom plant, also on the Leicester site, produces Sensations, Nobby's Crisps, Max deep ridge crisps, Chipsticks and Frazzles.

The products manufactured by Walkers use good ingredients and additives. The company has started using Sunseed oil instead of palm oil for frying. Compared to palm oil, Sunseed is healthier and higher in mono-unsaturates.

The company also introduced a healthier baked version of its crisps called Baked Walkers. The baked crisps come in different flavours and sizes. They are available in the normal snack pack, multipacks, 14s and 26-pack sizes.

In 2006, Walkers initiated a £12m project to expand its highly-automated warehouse facilities and improve production.

As part of the project, 10,000 pallet spaces were added to the Leicester site's southern distribution centre. The expansion increased the pallet spaces at the site to a total of 35,000.

Process

The potatoes arrive at the factory during the peak season of March to October from the fields. For the rest of the year they are stored in an environmentally-controlled environment. Upon arrival at the factory, the potatoes are floated out of the transportation trucks using water jets. This is done to ensure that the potatoes are handled carefully as it is essential that they are not bruised. If they are bruised, it results in lower quality brown crisps.

The potatoes are then peeled, sliced to the correct thickness and sent to the fryer. After being fried, the crisps are placed in a rotating drum where flavours are added. The crisps are finally packaged and sealed. Before being sent out of the factory, the operators at the plant to check the packets to ensure that they conform to the company's quality standards. The entire production process of conversion from potatoes to crisps takes only 20 minutes.

Schubert equipment

In order to boost production, Walkers ordered four TLM-F44 automated packaging systems from Schubert UK for installation in the fourth quarter of 2007. The systems were developed by IPS, Schubert's specialist packaging integration subsidiary.

System

The four packaging systems handle the packing of multi-bags of crisps by placing the three varieties of packet into horizontal flow wrappers (fill and seal). The TLM-F44 system is equipped with the carbon fibre TLM-F4 robot arm, which weighs 25% less than the previous aluminium version, allowing faster cycle times.

Operation

Storage hoppers above two vibratory bowl feeders supply the lines with 480 bags per minute. The system then uses optical detection to guide pick-and-place robots equipped with vacuum suckers to position the six or 12 packs into in-feed chain carriers. The packets are then sent to form, fill and seal flow wrappers.

The Schubert system uses its patented counter-flow technology where two chains operate against the flow of the product conveyor, making sure that there are only fully-loaded chain divisions.

Unidentified or incorrectly positioned crisp packets are sent back to the storage hoppers.

The systems were designed to handle a wide range of pack sizes (six, 12, 14 and 26) and are able to quickly change over to different product formats.