How to Choose a Metal Detector for Your Food Production Line

by | Nov 3, 2022 | Blog

How to Choose a Metal Detector for Your Food Production Line

If you have decided to install or replace a metal detector on your food production line, how do you ensure you choose the right one? You need to get a good return on investment, plus the metal detector has to be effective, i.e., it should reject products that are contaminated with as few false rejects as possible.

It’s essential you make the right choice when investing in a metal detector as the quality control and inspection programme in your manufacturing facility is essential for food safety.

Quality control and product inspection also help prevent expensive and damaging product recalls, ultimately protecting the reputation of your brand.

To help you choose the right metal detector for your requirements, we are going to highlight four main considerations:

  • Performance capabilities and ongoing optimisation
  • What you want the metal detector to do
  • Product characteristics
  • Inspection area conditions

We’ll also look at other considerations that are beneficial to take into account.

Eliminating False Rejects While Maximising Metal Detection Performance

It’s important that the metal detector you choose is capable of identifying contaminants, but it’s also important to prevent false rejects, i.e., where the metal detector identifies something as a contaminant when it is not. This is known as product effect.

The best solution is to choose a metal detector that cancels out product effect and delivers the highest levels of contaminant detection precision.

When considering product effect, there are two main technologies you need to look out for:

  • Multi-spectrum metal detection technologies
  • Machine learning capabilities

Multi-Spectrum Technologies

A multi-spectrum metal detector will use a range of different frequencies to filter out signals from the product, ensuring only contaminants are detected. This type of metal detector is much more effective than, for example, a metal detector that has just one frequency.

Machine Learning Capabilities

Every production line is different, and every product is different. Therefore, it is impossible to achieve the highest levels of contaminant detection precision using predetermined parameters. The solution is to choose a metal detector that has machine-learning capabilities.

We can use the metal detectors from our equipment partner Ceia to explain how machine learning works. Ceia calls the feature its auto-learn system.

When the metal detector is first set up, you run products through it so the auto-learn system can optimise the level of detection sensitivity based on the product’s characteristics and the speed of the line. In other words, the machine learning capabilities of the metal detector auto-customise the setup. This process can be repeated if you have multiple product types.

It is also then possible to run the auto-learn system on a Ceia metal detector in the background during normal operation of the line. The data produced during this learning period can then be analysed to identify additional optimisation opportunities that enhance the precision of the machine even further.

What Job Do You Want the Metal Detector to Perform?

Production lines have a wide range of requirements when it comes to metal detection. There can even be variable metal detection requirements on a single production line. For example, you might need very high levels of metal detection sensitivity on your packaging line as your product goes through final stage production processes before being shipped to customers.

However, metal detectors in earlier stages of the production process might not need such high sensitivity levels as their main job will be to protect equipment, i.e., by identifying pieces of metal that are large enough to damage production line equipment.

Therefore, it is important to ensure you get a metal detector suited to the sensitivity requirements of your production line and quality processes.

This often includes ensuring the machine is capable of detecting both magnetic and non-magnetic materials, including stainless steel, as well as both ferrous and non-ferrous metals.

Characteristics of Your Product

Different metal detectors are designed for different types of products. For example, a metal detector suitable for a salmon fillet line will be different from the metal detector required for granules, powders, or other loose materials. Whether the product being inspected is wet or dry is another important factor.

Therefore, it’s essential to consider the characteristics of the products on your line, including variations in product type and temperature, as well as product size.

Conditions in the Inspection Area

The location of the metal detector is another important consideration. Key factors include whether the inspection area is wet or dry, potential temperature changes, and the cleaning procedures on your production line.

For example, if your cleaning procedures call for low water pressure washdowns, a metal detector with an IP65 rating will be sufficient. However, if your cleaning procedures call for high water temperatures and pressures, you will need a metal detector with an IP69K rating.

Other Considerations When Investing in a Food Production Metal Detector

  • Connectivity – do you need to integrate the metal detector with existing equipment or systems?
  • Ease of use – is the metal detector easy to operate and optimise?
  • Cleanability – in addition to having an appropriate washdown protection rating, is the metal detector easy to clean?
  • Corrosion-resistant – does the construction of the metal detector give it high corrosion-resistant capabilities, particularly if caustic materials are used during cleaning?
  • Supplier – does the supplier have a strong reputation and proven track record?
  • Cost of ownership – the upfront capital investment required to purchase a metal detector is important, but it is also beneficial to consider the overall cost of ownership as this calculation will give you a more accurate understanding of return on investment.

Finally – Get Expert Advice

Our final tip for choosing a metal detector for your food production line is to get expert advice. As you can see above, there are many factors to consider, metal detection technologies are complex, and there is a wide range of different features available.

At SF Engineering, we have extensive experience helping customers choose the best metal detection solutions for their requirements. Get in touch to find out more or click here to browse our range of metal detectors.