Manufacturing Technology

With almost half a century of experience, Dutch company Weighpack International has grown from a small workshop, producing weighing machines for fasteners and hardware, into a leading company that designs, manufactures, installs and services complete packaging lines for the hardware sector.

Weighpack’s range of packaging machines includes over 50 different machines and is constantly being improved. This extensive portfolio includes automatic bin feeders, vibratory feeders, weighers and counters, case packers, palletisers, baggers, conveyors, cartoners, sealers and more. In addition to standard machines, most packaging lines are customised to meet specific customer needs – with the aim of delivering a wide range of high-quality products at the best value in the market. 

A prime example of how Weighpack is able to provide bespoke solutions is when it created a complete line for a leading fastener supplier in the US market. The company realised that dosing and packaging are critical steps between component production, storage and transportation. This is a specialist area where efficiency and precision are essential. Weighpack was asked to develop a bespoke solution for the entire bucket packaging process for fasteners, from product input to check weighing, lidding, labelling, printing and case packing – all whilst ensuring the most stringent requirements for packing quality and efficiency were met. As a specialist in the design of complete packaging lines for bulk hardware, Weighpack proposed a solution tailored to the customer’s needs, drawing on its nearly five decades of experience and innovative approach.

“The original Request for Quotation (RFQ) stated that we needed to design, manufacture, install and commission a fully automated and integrated packaging line, which could be controlled from a single point, and capable of accurately portioning and placing screws into
pre-formed plastic buckets – resulting in ‘retail ready’ sealed packs,” points out Weighpack. “With that in mind we developed a
tailor-made bucket packaging line, creating a system that not only met the customer’s immediate needs for flexibility, but also provided room for future expansion as the company grows.”

The configuration of the packaging line, designed for the organised packing of carbon steel fastener products into buckets, begins at the product infeed where the customer transfers items from internal bins to the main storage hoppers. Product flow from the 1,200kg capacity vibratory hopper is managed by a special vibratory pre-weigh tray, which directs products to a Z-shaped inclined slatted belt conveyor with waved edges. This conveyor feeds into a 14 head combination weigher capable of producing up to 35 buckets filling per minute.

Automated bucket dispensers de-stack stacked buckets and transfer them to a belt conveyor. Four buckets are then transferred to a
servo driven pocket conveyor at the end of the belt. This pocket conveyor indexes four buckets per cycle and presents them under the multi-head weighing system for filling.

The filling station is equipped with an orientation magnet to align longer steel fasteners inside the narrow containers. After an indexing sequence that includes check weighing, the buckets are automatically fitted with one to three drill bits and a driver bit before being lidded and labelled. The packaging cycle continues with a laser printer marking the buckets with production date codes.

Automatic case formers erect four-flap master cartons, which are then transferred to the case packer. At the end of the line, the case packer configuration loads three or four buckets into the master carton before sealing and labelling. A robotic palletiser will also be added to the line at the customer’s facility.

“Weighpack specialises in handling products with small volumes and high weights. Our strength lies in managing the entire process, from initial consultation to ongoing service and maintenance. All components within the Weighpack packaging line are also carefully designed and integrated to ensure seamless communication between sub-systems and ancillary equipment. This integration brings many benefits, such as trouble-free operation and efficient maintenance,” reports Weighpack. “Our customers also benefit from expertise in mechanical engineering, mechatronics and control technology, including both PLC and PC. This approach resulted in the final system that was designed and tested at Weighpack’s facility in The Hague, the Netherlands.”