Magnet Terminology & Definitions

General Terminology

📖Lift Safety & Inspection (ASME Focus)

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• Breakaway Force: The maximum amount of force required to vertically separate a magnet from a test plate. This is the "moment of failure" that determines the magnet's "true" lifting capacity under specific conditions. NOTE: Customers often think "High Gauss = High Lift Power," but that isn't always true. While Gauss measures field intensity at a point, Pull Strength (Breakaway Force) measures the total mechanical holding power which is a better test of true capabilities of the magnet.

• Safety Factor (3:1): The industry-standard ratio for lifting magnets. A magnet must be able to hold three times its rated capacity to account for unpredictable variables like surface scales, vibration, or uneven loads.

• WLL (Working Load Limit): The maximum mass or force which the product is authorized to support in general service. In magnet testing, we verify that the magnet can hold its 3:1 safety factor relative to this limit.

• Design Factor: The ratio of the ultimate (breakaway) load to the rated capacity. For permanent lifting magnets, this is strictly 3:1.

• ASME B30.20: The primary safety standard established by the American Society of Mechanical Engineers for "Below-the-Hook Lifting Devices." This standard requires annual, documented inspections and 3:1 safety factor testing for permanent lifting magnets.

• NIST Traceability: The "gold standard" for calibration. It means that the equipment used to test your magnets has been calibrated against standards maintained by the National Institute of Standards and Technology. This is a non-negotiable requirement for high-level audits (SQF, BRC, NASA).

• Below-the-Hook (BTH) Device: Any device (like a permanent lifting magnet) used to connect a load to a hoist. Defined under ASME B30.20, these require specific annual documentation.

• Qualified Person: As defined by ASME, a person who, by possession of a recognized degree or certificate, has successfully demonstrated the ability to solve problems relating to the subject matter (e.g., your certified technicians).

• Magnetic Saturation: The state reached when an increase in external magnetic field cannot increase the magnetization of the material further. This is critical when testing magnets on thin versus thick plates.

• Residual Magnetism: The magnetic field that remains in a material after an external magnetic force is removed. In industrial settings, excessive residual magnetism can cause parts to stick or attract unwanted metal debris.

📖Food Safety & Magnetic Separation (HACCP/SQF)

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• Pull Testing: A method used to measure the holding strength of a magnet using a certified scale or specialized pull-test kit. This is the standard verification method for magnets in the food, dairy, and pharmaceutical industries. While Gauss measures field intensity at a point, Pull Strength (Breakaway Force) measures the total mechanical holding power which is a better test of true capabilities of the magnet.

• Tramp Metal: Unwanted metallic contaminants (such as bolts, shavings, or wire) that accidentally enter a production line. Certified magnets are the primary defense against tramp metal in food safety programs (HACCP).

• Gauss Meter: A precision instrument used to measure the strength and direction of a magnetic field. At MagnetCert, we use NIST-traceable, calibrated Gauss meters to provide audit-ready data for food-grade metal separators.

• Flux Density: A measurement of the concentration of magnetic field lines in a specific area, typically measured in Gauss. High flux density is critical for capturing small "tramp metal" in food processing lines.

• HACCP 0909MAGSEP: The international standard for final magnetic separation devices used in food product streams. It dictates specific requirements for fabrication and magnet strength.

• Reach-Out: The distance a magnetic field extends from the surface of a magnet. In food safety, a high "Gauss" at the surface is useless if the reach-out isn't deep enough to catch metal in the center of the product flow.

• Air Gap: The distance between the face of a magnet and the surface of the load. Even a tiny air gap caused by paint, rust, or dust can significantly reduce a magnet’s lifting capacity. Our breakaway testing accounts for real-world surface conditions to ensure safety.

• Pole Plates: The steel disks between magnetic cartridges in a bar magnet. This is where the flux density is highest and where contaminants are most likely to be captured.

• Validation vs. Verification: * Verification: The annual "Pull Test" or "Gauss Test" to prove the magnet is still working.

  • Validation: The initial proof that the magnet's placement and strength are actually capable of removing the intended hazard (Tramp Metal).

• Rare Earth (Neodymium): The high-strength material used in most food-grade separators. It is highly effective but susceptible to "Heat Degradation" if not monitored.

• Dead Zone: The area on a magnetic separator where the magnetic field is weakest (often near the ends or mounting points). We test to ensure your "Dead Zones" aren't allowing contaminants to bypass the system.

• Ferrous vs. Non-Ferrous: Ferrous metals (iron, steel) are easily caught by magnets. Non-ferrous (stainless steel 304/316) is harder to catch. Explaining this helps customers understand why they might need higher Gauss/Pull-strength for food lines.

• Surface Gauss: The measurement of magnetic flux density at the surface of the magnet. While a common metric in food safety audits, it must be paired with a Pull Test to verify the magnet's true "capture" power.

💡 Technical Note: Calibration vs. Certification (Testing)

A common question we receive is: "Can you calibrate my lifting magnet?"

It is important to understand that permanent magnets (food or lifting) cannot be calibrated. Unlike an electronic scale or a pressure gauge, a magnet has no internal settings to "adjust" if its strength has faded.

• Testing & Certification: This is the process of measuring the magnet's current performance (Breakaway Force or Gauss) against its original manufacture specs and safety standards (like ASME B30.20 & SQF). We verify if the magnet is safe for continued use.

• The Verdict: If a magnet fails a pull test, it cannot be "turned up" or recalibrated. It must be serviced (if possible) or decommissioned and replaced to ensure operator safety.

In short: We don't calibrate the magnet; we certify its performance to ensure your facility stays compliant and your team stays safe.