Acquired as part of a production process redesign, the 530 pump is helping the company to reduce the time required for flavour changeovers from half a day to just five minutes.
At the heart of Moo Free’s factory in Holsworthy is the moulding line, where the company’s various flavours of chocolate are shaped into bars and other products. Until recently, the company relied on 14 individual 400kg tanks filled with chocolate. The required percentage of flavouring would then be added to each tank, before being wheeled to another location for tempering and mixing.
“We were losing a lot of time in constantly filling up these tanks and began thinking about how we could improve our manufacturing process,” explains engineering manager Simon March. “We also knew that if we no longer needed the tanks - which cost £15,000 each - we could sell them to help recoup any investment in new technology.”
Chocolate at Moo Free is produced in three-tonne batches and pumped into a large stainless-steel holding tank from where (until recently) it was transferred into the 400kg tanks ready for individual flavouring.
“By investing in a peristaltic process pump from WMFTG to dose the flavours, we conceived a way of transferring the chocolate directly from the holding tank to the moulding line,” says March. “This move has reduced labour and space requirements, and eliminated the need for the 400kg tanks, some of which have already been sold to more than cover the cost of the new pump. Importantly, the whole process has been simplified and is now more efficient.”
March commissioned the manufacture of a small stainless steel hopper which sits above the Watson-Marlow 530UN/R2 pump to provide gravity feed for the flavouring. After a tempering process, the chocolate passes through a mixing screw and into another hopper - it is the turning of the screw that provides the auxiliary signal for the dosing pump to introduce the flavouring (via a drive relay). The chocolate is mixed again before it ends up in a bar on the moulding line.
“Before selecting WMFTG, I looked at various dedicated dosing machines,” adds March. “A number of these systems relied on a Watson-Marlow process pump, but in a way that was far more complex than we required. Moreover, many of these solutions cost around £14,000. I knew that by simply acquiring a pump, for far less outlay, I could feed my system in a straightforward manner.”
Fully operational over a double shift (16 hours a day), the Watson-Marlow 530UN/R2 pump has proven 100% reliable since its installation in February 2020, dosing at a flow rate of 5-55mg/min from its location next to the moulding line. Moo Free takes advantage of the 520R pumphead for continuous tubing with runs on a 530 series pumps using Watson-Marlow's Marprene process tubing (4.8mm diameter bore).
Flavour changes are reasonably frequent at Moo Free, sometimes occurring twice a day, and it is here that the 530UN/R2 pump has delivered the biggest gains.
“Changing flavours is now a super easy job - I just use different Marprene tubing for different flavours,” states March. “We simply change the tube, empty and clean the hopper, fill it back up with another flavour and we’re ready to go again in about five minutes. Previously, every flavour change would take at least half a day to empty the chocolate from the 400kg tank and clean all the pipework associated with the tempering unit. Thankfully, those days are behind us.”