Having its cattle cake and eating it

Fighting to maximise the efficiency and effectiveness of its manufacturing processes in order to stay ahead of its competitors is Rumenco. Its three production lines produce a range of cattle and sheep feed blocks, which weigh in at between 18kg and 25kg at rates up to 900 units per hour, typically comprising barley, molasses, rapeseed, soya meal, salt and urea – plus an assortment of minerals and medications. Demand can be seasonal with each of the lines working 24h/day for maybe six weeks non-stop at peak times, so equipment reliability is important.

Dry raw materials are first metered onto a conveyor line before passing through a mixer. They are then transferred to a continuous wet mixing unit, where molasses is added. The moist ingredients are then metered into circular moulds on a four-station indexing table. A 1600lbf/in2 hydraulic ram forces the mix into the mould, before finished blocks are ejected on to a second line for packing.

The performance of the indexing mechanism controlling the turntable unit is crucial, and obtaining spares to IP65 classification for the ageing equipment became increasingly difficult.

Expert UK quoted for the job and after an evaluation of the existing plant, offered a proposal covering reliability, positional accuracy, and the ability to increase production and cut running costs.

Central to the proposal was the use of its indexers to control the turntable mechanism. Lighter and smaller than the gearbox it replaced, the new unit delivers significant productivity benefits by indexing the 1tonne turntable, complete with moulds, 25% faster than before. By employing an inverter to enhance its deceleration characteristics, the new unit provides improved positional accuracy and requires a 1.5kW motor, compared with the 4kW model previously used.