Bespoke Engineering
Tony Conroy is the Head of Engineering at Graham & Brown’s wallpaper production facility, where externally sourced printing lines are augmented by bespoke machines. “We designed and manufactured our own wrapping machines in order to optimise our completely automated production process,” Tony explains.
Non-stop Production
Graham & Brown’s unique wallpapers start out as 6,500m reels of 1.1m wide paper. Depending on the design, the unwound paper passes a choice of 5 machines with up to 12 printing stations per machine. Each station adds colour and design, coating with ink or PVC. The paper is then heat treated in each set’s oven at up to 165˚C to “gel” the PVC. “The ovens are heated solely by the heat recovered from our incinerator’s combustion process,” Tony explains. After the ink/PVC application, the paper passes horizontally through a 24 metre long oven up to 205˚C, where high velocity nozzles are used to expand the product. The final product is automatically trimmed, wound into 10 metre rolls, wrapped, labelled and put into cartons, then conveyed over 200 metres to a robotic palletising plant.
Heat Recovery
“In 1985, Graham & Brown was the first in its industry to use a heat recovery incinerator to burn potentially harmful emissions from the vinyl coating lines, then re-use the heat for the production process,” explains Ian Brown, Director responsible for Corporate Social Responsibility (CSR).
Tony adds, “The first incinerator was replaced by a more efficient model in 1996, when we also added extraction systems. Eight years ago, we added a second incinerator. All the ovens in our printing sets are heated by thermal oil. The incinerators burn the exhaust air from the printing process to create clean, hot air, which is then used to heat the oil. It’s a closed loop system, and today the incinerators supply around 70% of the total process heat we require.”