One of the largest rice cooperatives in North America has more than 50 Fortress Technology metal contaminant inspection units installed in its processing plants, including 13 ground-breaking incline conveyor metal detectors. Being able to upgrade to the latest, greatest inspection features is why this bulk rice processor has remained loyal to Fortress for close to two decades.
The ‘Holy Grail’ of any food machinery investment is to maximise Total Cost of Ownership in a sustainable way, without compromising performance and consumer safety. Continuing to benefit from Fortress Technology’s contaminant detection ‘Never Obsolete’ pledge, this dry rice manufacturing and packing facility now has in excess of 50 gravity, bulk, lab unit and incline conveyor metal detectors.
Processing and packaging more than 100 long and medium-grain rice brands – supplying retailers, restaurants, food service companies and exporting globally – Fortress has supported the farmer-owned rice cooperative by issuing a number of technology and machine upgrades.
Analogue metal detectors more than 10 years old have been converted to digital to improve contaminant detection and add data logging and reporting capabilities. Making them comparable to new Fortress metal detectors. However, in the latest and largest project, Fortress surpassed itself by reconditioning and mounting 13 existing metal detector heads onto new incline conveyor frames robustly designed to transport heavier bags of rice, introducing an innovative bi-directional sweep reject.
From soil to steam
Harvesting, milling, grading and packing over 60-million rice bushels annually, the US producer is reliant on robust best-in-class metal detection. Upstream, prior to packing, are a number of Fortress Gravity metal detectors located between product shoots and hoppers. Each rapidly inspects between 40,000 and 75,000 cubic feet of free-falling dried long-grain rice hourly, automatically rejecting metal contaminants from the product flow and keeping rice waste to a minimum.
Compact offline lab units are then deployed to quickly examine any rejected product and separate the metal contaminants from the rice. This enables the rice producer to filter out and rework all good product, again helping to minimise waste and identify contaminants for further investigation.
For bulk bags of rice weighing up to 50kg, large bag metal detectors are, for weight and safety reasons, located at floor level. Featuring a large aperture, a special coil structure, and Vector heavy duty conveyor, this market-leading bulk inspection metal detector can guarantee detection of ferrous and non-ferrous metals as small as 1.5mm, and 2.0mm non-magnetic 316 stainless steel contaminants in the aperture centre.
To inspect smaller rice packs weighing up to 9kg, Fortress engineered a special incline conveyor frame to overcome the plants’ limited floor space. Measuring 4.25 metres in length, packs move up a special flighted conveyor belt at a 45° angle.
Designed to handle a fast product rate, a Stealth metal detector with a customised head and aperture ensures performance and detection sensitivity is not forfeited. Having ground level remote access enables staff to safely select the inspection parameters and access data from the metal detector heads if the HMI control panel is beyond reach.
Sustainable and waste reducing
Many Fortress engineers contributed to the design. Yet, as testament to the level of detail and collaboration that goes into each and every Fortress commission, company founder and President Steve Gidman couldn’t restrain himself from getting involved.
Steve reflects: “Because the conveyor was inclined and as the product had to be rejected perpendicular to the flow, rubber grips were not advisable as they would inhibit reject performance, damage bags and make a mess. Knowing that this would create unnecessary waste, to address this we instead opted for belting with flighted sections. This solution allowed the rice bags to be conveyed uphill at a steep angle, without impacting the lateral rejection.”
Due to the high product rate – on average 150ppm – and the flighted belt, deploying a reject device with a return stroke was ruled out. To avoid collisions with the belt features and trailing rice bags, Fortress instead created a bi-directional paddle sweep reject. Rejecting contaminated packs on either side of the conveyor, chutes funnel rejected product safely to ground level, securing it behind lock and key for authorised quality control personnel to remove.
For this customer, like many, the sensitivity of each metal detector combined with the compatibility of components, provides added assurance that investments can be spread out. Knowing that the technology will never be obsolete is especially valued by this customer. Parent company Fortress Inc is currently in the process of upgrading more than 10 Phantom metal detectors to Stealth, on machines purchased by this rice producer over 10 years ago.
“Very often, metal detection hardware remains fit for purpose long after the software has evolved. Many fast-growth companies approach us to discuss adding extra features, including sophisticated data logging capabilities,” explains Fortress Europe’s Managing Director Phil Brown.
Because Fortress always sticks to its universal modular design, upgrading to a Stealth Metal Detector is very straightforward. Not only does this save customers a lot of money disposing of and replacing assets that remain perfectly functional, it also prevents industrial assets adding to the environmental costs. Being able to offer this upgrade service and additional field support is a huge tick for responsible waste stewardship, reports Phil.
