The use of metal detectors deliver significant benefits across industrial, scientific manufacturing and healthcare sectors. Their challenge on how to maximize product quality, improve efficiency and provide protection to consumers, retailers, and the brand has long been address - ensuring an accurate detection of metal contaminants in packaged products.
Moreover, it is important that metal detectors are maintained, installed, and operated properly. Not only this will extend the life the equipment, it will also contribute to enhance product quality and minimize losses. However, properly sustained metal detectors will not guarantee a precise inspection of metal contaminants of confined goods while it travel along a conveyor line. The performance and sensitivity of metal detector is highly dependents on many factors.
As an award-winning manufacturer of industrial and laboratory balances, scales, and weighing systems, A&D Inspection is here to help you determine the factors that are essential in achieving operational efficiency while selecting your metal detector.
Sources of Contamination
Metal contaminants can infiltrate the product and process from a variety of sources. Identifying these sources is a crucial phase for an effective metal contamination detection. For this reason, reliable and effective metal detector system like EZI-Check™ Metal Detector which provides an accurate detection and rejection solution should be considered.
Normally, potential contaminants come from the following:
Raw materials coming from ingredients, metal tags and lead shot in meat, wire in wheat, wire, tractor parts in vegetables, hooks in fish and many more.
Personal sources including earrings, rings, coins, keys and hairclips.
Maintenance tools covering all all items carried out during clean-up or maintenance.
Processing equipments such as machine parts and materials coming from wear and tear. Examples are broken screens, metal slivers from milling machines, and foil from recovered products.
Factors Affecting Sensitivity
Major consideration in selecting a metal detector is its high-level of sensitivity when inspecting contaminated products and further rejecting them. Metal detector such as EZI-Check™ Metal Detector has a high sensitivity detection and its optimal sensitivity can be set through the auto sensitivity settings.
Moreover, the sensitivity of a metal detector during the actual operation is influenced by several factors such as type and shape of metals, the product, environmental condition and many more.
- Metal type can be classified into three: Ferrous, nonferrous, and stainless steel. Depending on the type of metal contaminants present, the level of sensitivity of equipment varies. The magnetic permeability and electrical conductivity of the metal is a crucial factor on the ease of detection. Non- Ferrous metals like copper, aluminum and lead are easy to detect as they are good electrical conductors.For example, ferrous metal contaminants is easy to detect because it is magnetic and a good electrical conductor. While non-magnetic, Non- Ferrous metals like copper, aluminum and brass are easy to detect as they are good electrical conductors. Stainless steel, on the other hand, has a varying conductivity.
- Shape and orientation of metal is also important in metal detector’s sensitivity. Typically, a sphered-shape metal is standard during product inspection. The orientation of the metal when it passes into the metal detector can affect the sensitivity as well.
- Environmental condition such as electromagnetic interference, plant vibration, temperature fluctuations affects the performance of metal detector especially when conducting high sensitivity detection.
- Product characterics should be considered when adjusting the sensitivity levels of your equipment. Inspection is easy for dry products like snacks, rice and confectionery. Wet including fresh meat, poultry, cheese and fish, on the other hand, creates an interference signal in the detector which needs to be cancelled-out before running the metal detector.
Components of Metal Detector
Proper installation and operation of metal detector will help diminish metal contamination. Thus, it will protect your brand and win more consumers in the process. It is essential as well to test the performance of the equipment in regular basis.
A typical metal detection system consists of four main parts:
- Detector Head is the part of metal detector that determines the potentiality of metal contamination. It is the detector head that gives signal to control system which immediately alert the personnel and remove product from the product line when metal contaminants are detected.
- User Interface/Control Panel is the front-end of the electronic control system. Adjustments in machine sensitivity are made in this section
- Transport System is the part which moves the product through the metal detector. Mostly, a conveyor belt and a non-metallic tube that moves the product through the aperture (In case of liquid or powder-based materials)
- Reject System often use to remove any contaminated product from the production line. Depending on the product and transport system, various methods are use such as push arm, air blast, drop flat, and value divert.
Design Features Consideration
Deciding to choose a metal detector base on its sensitivity level and range of features alone are not the only things to consider before purchasing. While sensitivity is important, here are other key factors that you should keep in mind when finding the right metal detector:
- Stability - A stable metal detector is associated with a top-quality equipment. It can run in a steady operation without false rejects or inconsistent detections and not requiring occasional adjustment. Unstable metal detectors can similarly provide same sensitivity levels but the decrease in performance will be evident overtime.
- Electronic Drift - Changes in sensitivities or “drift” appears over a period of time due to temperature variation and electronic components deterioration. This factor can affect the sensitivities of the metal detectors and may result into false alarms. There are design features that can help in removing the drift including Quartz Frequency Control, Automatic Temperature Stability Control and Auto Balance Control
- Repeatability - The ability of a detector to inspect a test sample repeatedly is critical to minimize errors during the process. At the same time, it will increase its user’s confidence for the equipment and lessen the need for product re-inspection.
- Ease of set-up and use - There are metal detectors that possess features including ‘automatic set-up’. Typically, these equipments are geared with common setting or similar products grouping allowing a minimal error during setup and operation. Looking for metal detector that can conduct high sensitivity detection with simple and easy operation? Browse through EZI-Check™ Metal Detector model on A&D.
- Self-Checking and Condition Monitoring - This feature is beneficial to create an advance warning against future system breakdown. With these feature, it will lessen the trouble of scheduled testing and condition monitoring.
A&D Inspection has been providing industry-leading precision weighing and measurement equipment to laboratories across the world for over 40 years. At A&D Inspection, you can rest easy knowing that each piece of equipment passes through the highest of quality standards at ISO 9001 certified facilities.
To view A&D Inspection’s complete line of Metal Detectors and Accessories visit our website today and we’ll provide you with worry-free and convenient warranty services for guaranteed product performance and quality satisfaction.