RTS' magnetic robot system helps Warburtons to national success

Citation

(2005), "RTS' magnetic robot system helps Warburtons to national success", Industrial Robot, Vol. 32 No. 5. https://doi.org/10.1108/ir.2005.04932eaf.002

RTS' magnetic robot system helps Warburtons to national success

RTS' magnetic robot system helps Warburtons to national success

Keywords: Pallets, Robotics, Materials handling

The decision ten years ago, to become a national baker rather than one with a northwest stonghold, necessitated an analysis of every area of the business. Retail businesses were divested and marketing became more imaginative, but one of the most crucial questions remained unanswered, “how to produce the volumes expected of a national baker?”.

The job of answering that question fell to Peter Haworth, Warburtons operations service director. “We knew we had to automate, but the question of how easn't obvious”, said Peter. Loading the bread tins on and off the conveyors was a difficult job even when they were done singularly, as the tins are often still hot from the ovens. However, as demand increased, the tins were strapped together and so got heavier and heavier. “In the end”, said Peter, “the tins ere strapped into groups of eight or ten and we knew the position was untenable”.

A trawl of automated solutions developed elsewhere in baking drew a blank. John marshall, the Warburtons engineer behind the implementation of the robots, explained: “We knew we had to look for a more innovative solution already in use outside the bakery sector. The RTS gantry robot system at Pilkington Galss seemed promising, so we investigated whether it could be adapted for our purposes. It could”.

Instead of the unreliable robot “fingers” used elsewhere, the Warbutons/RTS solution uses magnets to pick up and set down the bread tins. It copes with strap sizes far exceeding the lifting abilities of a human. As well as being able to manage slight variations in tin shape and size. The ability is vital, because the tins do tend to become deformed over time, owing to the constant heating and cooling they undergo. The gentler handling of the tins by the robots has had another, surprising result, the tins now last rougly twice as long as they did previouysly. This an important consideration when each of Warburtons large plants has 1,200 tin sets and each of those sets costs £60,000.

Warburtons now has 11 bakeries (five of them opened in the last decade) across the UK and produces over two million bread products a day. All these plants operate 22 hours a day and produce between 6,500 and 8,500 loaves per hour. This year will see the opening of a new £60 million bakery near Wakefield. Once again, the RTS magnetic gantry robot solution is to be used, bringing the number of tin and lid storage systems in use by Warburtons to 25.

Peter Haworth commented: “We have been fortunate in having a real partnership with RTS. We tell them what we want and they devise the engineering solution. The resulting system is clean and quiet, whereas others are not”.

When the bakery wishes to exchange a tin type, a carriage containing up to ten magnet heads, removes the current tins from the bakery conveyor circuit and places them into storage. The system then retrieves new tins from the store and places them onto the outleg conveyor ciruit. Each RTS two axis gantry, is around 5 m wide by 20 m long and has a pay load capacity of approcximately 1,200 kg (Plate 2).

Plate 2 Warburtons knew they had to automate to produce the volumes expected of a national baker

Over the years, the basic premise behind the system has been continually improved and refined for greater Overall Equipment Efficiency (OEE). Recent improvements added individual releases on the magnet heads and a new, easier to use operator interface. David Bradford, MD of RTS Flexible Systems, explained: “In a bid to decrease the cycle time, the latest systems will be supplied with an upgraded control system. This will allow the robot to maintain speed as it swoops down to release or pick up the tins without even pausing. We are confident that our Wakefield installation will do with just two gantries what others would do with three. In fact, we expect that these small refinements, when taken together, will knock two seconds off a thirty second cycle time”.

Web sites

Warburtons: www.warburton.co.uk

RTS group: www.rts-group.com

RTS Flexible Systems: www.rts-group.com/flexible-systems