Ishida multihead weighers are playing a critical role in helping one of the UK’s largest frozen vegetable processors and packers increase throughput by as much as 20 percent.
The five Ishida weighers at the Pinguin Foods UK site in Kings Lynn include an advanced 24-head CCW-R multihead weigher with three litre hoppers for mixed vegetables and four five litre hopper 14-head models for single varieties, which include carrots, peas, sweet corn, beans, broccoli and cauliflower.
On the lines where the Ishidas have been installed, along with new colour sorters which check for and reject substandard vegetables, overall weighing accuracies are now running at under 0.7 percent deviation from the target weight compared to around 1.8 percent previously.
The Ishidas are handling pack sizes of between 125g and 2.5kg, including mixed vegetables of two, three and four varieties on the 24 head mix weigher. In addition, the weighers can be used for special pack requirements. For example, one weigher in ‘double dump’ format is being used to pack 10kg boxes, where it has effectively doubled speed and greatly improved accuracy over the previous method.
"Another major advantage is their flexibility; we can easily switch product from line to line depending on requirements, something that was not possible with our previous volumetric and older multihead models," said Packing Hall manager, Steve Walton.
Part of this flexibility is thanks to the ease of changeover on the Ishida weighers. Product specifications including target weight are pre-programmed into the easy-to-use remote control unit for changeover at the touch of a button. The waterproof construction of each model and easy to remove change parts also mean clean down can be carried out quickly and efficiently.
The weighers are part of an ongoing multi-million pound investment in both the processing and packing operations at Kings Lynn, involving the installation of hi-tech equipment throughout, such as the state-of-the-art colour sorters that can detect imperfections in the vegetables and reject them at high speeds. Another key focus of the investment is on improvement in energy efficiencies. Again the Ishida weighers are playing an important part in this, along with Pinguin initiatives such as reduced water consumption and the introduction of more efficient lighting.
The weighers are in operation 24 hours a day, five days a week, with additional weekend working during busy seasons such as the run up to Christmas. Typical speeds currently are around 75 packs per minute for a 1kg pack, well within the weigher’s capabilities of 90 packs per minute.
"We are continuing to work on further developing the performance of the lines," explains chief engineer, Paul Spurrell.
"Our focus is not just on speed but on delivering consistency and ensuring that the weighers are fully integrated so that they work as efficiently as possible with existing equipment."
To cope with higher line speeds, the company also had to introduce new checkweighers, also from Ishida.
The DACS-W checkweighers feature Ishida’s unique DSP (Digital Signal Processing) chip which permits accurate signal processing under a wide range of weighing conditions, together with an Ishida built load cell that delivers high sensitivity, response and accuracy.
Speed and accuracy are further enhanced by the light weight conveyor, enhanced direct drive motor and a special low friction belt.
"In the few months that they have been installed we have already achieved a 15 percent improvement in throughput so we are well on the way to reaching our 20 percent target," said Spurrell.