2. Fortress Technology Ltd. www.fortresstechnology.com 1 Metal Detection - The Basics North America Fortress Technology Inc. Toronto, Canada Phone: (416) 754-2898 Fax: (416) 754-2976 Email: fortress@fortresstechnology.com Europe Fortress Technology (Europe) Ltd. Banbury, UK Phone: +44 (0) 1295 256266 Fax: +44 (0) 1295 265277 Email: europe@fortresstechnology.com

3. Fortress Technology Ltd. www.fortresstechnology.com 2 Contents 1. Metal Detection - The Basic Principles 1.1 Theory of Operation 1.2 Product Effect and Phasing 1.3 Metal Free Area 1.4 Sensitivity 1.5 Types of Metal 1.6 Shapes and Orientation 2. Testing 2.1 Test Sample 2.2 Frequency 2.3 Procedure 2.4 Records 3. Sources of Interference 4. Applications 4.1 Conveyor (End of Line) 4.2 Gravity 4.2 Pipeline 5. Good Practice Guidelines

4. Fortress Technology Ltd. www.fortresstechnology.com 3 Balanced Coil Receiver 2 Transmitter Coil Receiver 1

5. Fortress Technology Ltd. www.fortresstechnology.com 4 Balanced Coil Receiver 2 Transmitter Coil Receiver 1

6. Fortress Technology Ltd. www.fortresstechnology.com 5 Product Effect Conductive ScaleMagnetic Scale

7. Fortress Technology Ltd. www.fortresstechnology.com 6 Phasing Resistive (Conductive) R Reactive (Magnetic) x Stainless Steel (1 mm) I.e 304. 316 Non Ferrous (1 mm) I.e. Copper, Brass, Ali. Ferrous (1 mm) I.e. Iron Steel 0

8. Fortress Technology Ltd. www.fortresstechnology.com 7 Phasing With Product Reactive (Magnetic) x Resistive (Conductive) R Stainless Steel (1 mm) I.e. 304. 316 Non Ferrous (1 mm) I.e. Copper, Brass, Ali Ferrous (1 mm) I.e. Iron, Steel Conductive/ Wet Product (meat, cheese, moist bread)

9. Fortress Technology Ltd. www.fortresstechnology.com 8 Metal Free Area Total Metal Free Area

10. Fortress Technology Ltd. www.fortresstechnology.com 9 Sensitivity Metal Size Aperture Size 1 2 3 1 2 3 Position in Aperture Signal Size

11. Fortress Technology Ltd. www.fortresstechnology.com 10 Types of Metal 2.0mm Fe 2.0mm Non Fe 3.0mm SS Dry Product Mode (Example of Ratios ONLY) Wet Product Mode 2.0mm Fe 3.0mm Non Fe 4.0mm SS

12. Fortress Technology Ltd. www.fortresstechnology.com 11 Shapes & Orientation of Metal A B C Ferrous Wires: A - Easiest position, biggest signal. B, C - Hardest Position, smallest signal. Non-Ferrous and Stainless Steel Wires: B, C - Easiest position, biggest signal. A - Hardest position, smallest signal. Travel

13. Fortress Technology Ltd. www.fortresstechnology.com 12 Typical Guidelines for Sensitivity Dry Product Ferrous & Non Ferrous Wet Product Ferrous Non Ferrous Aperture Height Up to 50 mm (2 In) Up to 125 mm (5 In) Up to 200 mm (8 In) < 0.8 -1.0 mm< 1.5 mm< 2.0 mm < 1.0 -1.2 mm< 2.0 mm< 2.5 mm < 1.2 - 1.5 mm< 2.5 mm< 3.0 mm

14. Fortress Technology Ltd. www.fortresstechnology.com 13 Detector Performance Isolated Rollers - prevent loops High Quality Belt - Metal Free, Carbon Free, Interlocked finger Splice, or Plastic Modular Belt (White or Natural) Low vibration and Static Adequate metal free area 6. Roller Isolation 3. Clearance4. Foot Isolation 5. Metal Free Belt 1. Metal Free Area 2. Non-Metallic Slider Bed

15. Fortress Technology Ltd. www.fortresstechnology.com 14 Typical Metal Detector Conveyor Reject Reject Options Reject Retracting Belt Flap Gate Air Blast Reject Photo Eye Diverter Pusher

16. Fortress Technology Ltd. www.fortresstechnology.com 15 Drop Through / Gravity Metal Detector Good Product Output Reject Output Detector To Valve Distance Product Freefall Start Point (Test Piece Access) Plastic Pipe Selection Detector Overall Length Drop Height Distance D1 D2

17. Fortress Technology Ltd. www.fortresstechnology.com 16 Drop Through / Gravity Metal Detector A drop through / gravity detection system is ideally suited to inspecting dry, free flowing products such as : Grains, flours, cereals Rice, nuts, sugar Plastic pellets and flakes The following critical factors must be known when designing a successful drop through / gravity detection system: Flow rate Bulk density Free fall distance Pipe size Space available Testing procedure (insert + recovery)

18. Fortress Technology Ltd. www.fortresstechnology.com 17 Pipe System Flow Good Product Rejected Product D1 Detector Reject Valve Non Metallic Pipe Section

19. Fortress Technology Ltd. www.fortresstechnology.com 18 Pipeline Metal Detector A pipeline inspection system is ideally suited to inspecting liquid, slurries or paste products that can be pumped through. Typical pipe products would include: Sauces Dairy products Meat slurries Juices etc. The following critical factors must be known when designing a successful pipeline detection system: Pipe I.D. Pipe clamp connection style (tri-clamp, I-line etc) Product flow rate (GMP) Product viscosity Product temperature range Product pressure Expected cleanup procedures (wash down, pipe pig, etc.)

20. Fortress Technology Ltd. www.fortresstechnology.com 19 Metal Detection System Sensitivity Q&A Test Form Location Date & Time Samples Used Results (signals) Corrective Action

21. Fortress Technology Ltd. www.fortresstechnology.com 20 Good Practice 1. Prevention 1.1 Training 1.2 Controlled Maintenance 1.3 Regular Inspection & Good Housekeeping 2. Sensitivity 2.1 Identify Standards for products (maximise sensitivity) 2.2 Use Security methods (passwords) 3. Testing 3.1 Determine Frequency 3.2 Create Test packs 3.3 Document 4. Rejected Product 4.1 Isolate & screen 4.2 Repeat 3 times / change orientation 4.3 Investigate – trained personnel / off line 4.4 Identify potential source& resolve 5. Maintain Records 5.1 Test / Production / Maintenance