Northseafood Holland BV, a leading supplier of flat fish, has responded to market demand for different pack presentations and doubled its packing speed while increasing accuracy, following the installation of a special 14-head weigher from Ishida Europe.
Northseafood supplies supermarkets in Italy, France, Belgium, Austria, Sweden as well as the Netherlands from its plant in Urk, where white fish fillets are either frozen and glazed or crumb-coated, IQF (individually quick frozen) and then immediately packed.
Ishida was called upon to make modifications to a key packing line including the installation of the new multihead weigher, to improve performance and enable the line to pack bags as well as cartons.
The key motivation for change was the need to offer different pack presentations but there were several additional factors.
The company’s previous line featured a 12-head linear weigher which discharged frozen fillets into cartons at 20 packs a minute, a level of throughput which threatened to limit the company’s growth. In addition, the accuracy of the line was no longer acceptable and the length of the product (up to 250mm) and the fragility of the glaze or coating also presented special weighing and packing challenges.
Underneath the new Ishida multihead weigher is a special system which can either catch the product in a double-opening timing hopper, leading to the bagmaker, or divert it via a chute to the cartoner. The system is contained in a frame, which is moved by a pneumatic arm into the chosen configuration.
With the target weights being as low as 270g, and the individual fillets weighing as much as 90g, a reject option was essential for high-speed operation. The length of the product meant that a standard error hopper would be unsatisfactory and could cause product bridging. When packing into bags, therefore, any weighment which trips the metal detector or is outside the acceptable weight range, causes the frame to move, bringing the chute in line with the outlet and diverting the product into a reject bin.
To handle the long, fragile product, the multihead weigher has flat radial feeder troughs with waterfall ends. The five-litre pool hoppers are fitted with shrouds, while extra large seven-litre weigh hoppers are used, enabling gentle product handling. To reduce product breakage further, the discharge chute is at a ”gentle angle” of 45°.
The weigher is mounted on a stainless steel gantry and surrounded with a temperature-controlled cabinet that keeps it at a steady -5°C. A special booth is attached, where weigher contact parts can be laid out on racks for fast cleaning and replacement.
In addition to installing the new equipment and re-working the existing carton line, Ishida also fitted the belt conveyor with an infeed hopper which functions both as a buffer and as a way of bringing product into the packing stream from off-line sources. This enables the new packing system to serve other lines and product sources, thus further increasing the versatility of the Northseafood’s plant.
