This website uses cookies primarily for visitor analytics. Certain pages will ask you to fill in contact details to receive additional information. On these pages you have the option of having the site log your details for future visits. Indicating you want the site to remember your details will place a cookie on your device. To view our full cookie policy, please click here. You can also view it at any time by going to our Contact Us page.

Close

Automatic QC testing for metal detector

07 November 2023

An automatic testing solution has been deployed by a supplier of frozen potato products to help ensuring product integrity and premium quality from farm-to-freezer-to-table.

The frozen potato provider has installed metal detectors, each equipped with customised reject conveyors and an automatic testing capabilities at the end of all of its processing liens to provide a final and robust quality check. 

Every hour, each of the Stealth metal detectors, supplied by Fortress Technology, automatically perform up to nine machine validation tests – equating to 180 or more repeatable tests on multiple SKUs and different-sized bags of french fries, ranging from 225g to 9kg. The deployment of Halo Automatic Testing ensures tests are never skipped. The solution also helps to minimise bags of frozen fries being split open to insert test wands, and consequently good product being damaged and wasted. Additional engineering safeguards also ensure quarantined metal-contaminated products are not re-introduced to the upstream processing line.

Testing the performance of conveyor metal detectors is typically done manually. However, the challenge for an operation of this scale is dedicating the resource and time to conform to multiple quality control testing criteria set by suppliers and switching between multiple product SKUs. Especially on high-speed processing lines operating at 150ppm with a frozen product range. 

Simulating real conditions
Simulating real production conditions, Halo enables the frozen fries processor to program and conform to every customer’s performance verification testing program. Including independently testing all three metals in the leading, trailing and middle of product bags – a request stipulated by one customer.

‘Product effect’ was the main rationale for these additional checks. The reason being is that in bulky frozen products weighing up to 9kg, performing just one test could result in high levels of false rejects. This can not only distorts results but could lead to potentially high volumes of good product being wasted.

“By testing all three metals in three positions ensures the metal samples are not being masked by the product in any position and also confirms that the reject system is tracking correctly. This is especially important in frozen bulk products when the characteristics might change due to slight thawing during the inspection phase,” explained Jodie Curry, Commercial Manager at Fortress Europe.

Switching and adapting to different test routines also straightforward. For customers whose COP standards only require one pass of each metal sample hourly, or at the start and end of daily production, the infeed sensor of the metal detector picks this up. Communicating with Halo to perform the verification tests aligned to each product SKU and inspection standard. 

Each production line will only halt if the metal detector performance test or reject check fails. To assist with audit traceability, each individual metal detector automatically captures and saves all the data. Quality personnel can call up this digital data for a documentation review whenever it is required and extract reports via USB. Providing a reliable machine performance and due diligence audit trail. 

To ensure quarantined rejected products are never reintroduced to the processing line several extra failsafe features were also added. This included equipping each reject bin with magnetic locks and issuing controlled security card access to authorised personnel only.  

The reject bin automatically unlocks for any products rejected during the Halo test, enabling personnel to move the bags back upstream to be re-inspected. However, to distinguish between a genuine contaminant rejection and product isolated during the Halo performance verification test, the metal detector bin door automatically remains locked if a reject was already present.

Fortress estimated a payback of less than several months on the original investment. This factors in the combination of eliminating human errors, eradicating workforce safety risks, labour savings and reduced product waste. Meaning that each Stealth metal detector equipped with Halo for this frozen potato supplier has already potentially paid for itself more than 30-times over! 


Contact Details and Archive...

Print this page | E-mail this page