1. Repair Methodology for Steel Cord Belts to Increase Life and
Reduce Operational Risk. Alex Harrison, RPEQ Conveyor Technologies
Pty Ltd 2014 Conveyor Technologies Pty Ltd. All Rights
reserved
2. 2014 Conveyor Technologies Pty Ltd. All Rights reserved
COLLECT DAMAGE INFORMATION BEST ACHIEVED BY REMOTE ACCESS TO A NDT
MONITOR Main Types of Damage : (a) Impact (b) Fatigue at Defects
The NDT Monitor : Dual Frequency E-M plus Magnetic Induction
3. Damage by Impact Belt damage is not always visible ! Steel
cables break due to Impact and/or Fatigue Fabrication Defects
4. Damage by Fatigue Manufacturing Defects Steel cord belts
contain defects from new. Steel cables break from : Bending
Fatigue, Flexing, Stress Concentrations at Defects Press-mark
Defects Edge cord defect
5. STEPS IN REDUCING RISK MAXIMISING BELT LIFE 2014 Conveyor
Technologies Pty Ltd. All Rights reserved Collect damage
information at regular intervals from a remote NDT belt monitor
(Belt Scan). Conduct a strain analysis on damage site. Determine
belt Safety Factor (SF) at damage sites, in order of severity.
Design a Repair for load-carrying, depends on damage shape and
cable-end distribution. Install repair and Test its Quality : Hot
vulcanized in-laid cable repair, with belt tension removed [1]. 1.
The Belt : Steel Cord Composite Construction (AS-1333) 2. Steel
cables share load and redistribute stress imbalance by Shear.
6. 2014 Conveyor Technologies Pty Ltd. All Rights reserved
RECORDING BELT CABLE DAMAGE Remotely Accessed NDT Belt Monitor.
Equipment shown was installed in 2001, Henderson Mine PC-3 belt ,
Colorado
7. 2014 Conveyor Technologies Pty Ltd. All Rights reserved
COLLECTING NDT DATA Steel cord belts remotely monitored annually =
150 In Australia : Queensland (12 / year) In North America : USA
(130 / year) Canada (8 / year Peru (1 installation) 4
8. RECORDING BELT CABLE REINFORCEMENT DAMAGE 2014 Conveyor
Technologies Pty Ltd. All Rights reserved Expand
9. EXPANDED DATA EVENT LOCATION AND TYPE 2014 Conveyor
Technologies Pty Ltd. All Rights reserved
10. RECORDING BELT CABLE DAMAGE 2014 Conveyor Technologies Pty
Ltd. All Rights reserved
11. SPLICE ADHESION MONITORING 2014 Conveyor Technologies Pty
Ltd. All Rights reserved 8-2014 : Damaged Splice Signature
8-2013
12. CORD PLANE DEFECT FATIGUE (Press-length Interval cord plane
buckles) 2014 Conveyor Technologies Pty Ltd. All Rights
reserved
13. EMBEDDED LOOP CAUSING CABLE FATIGUE
14. SELECT THE NDT SCAN INTERVAL : REMOTE ACCESS TESTING 2014
Conveyor Technologies Pty Ltd. All Rights reserved Corrosion and
Cable Break Growth 1 to 3 Months. (Annually too long) Impact damage
use other detection devices
15. REPAIR DESIGN REQUIRES ACCURATE DAMAGE ASSESSMENT COMPARING
NDT MONITORING SYSTEMS 2014 Conveyor Technologies Pty Ltd. All
Rights reserved bs1 = Belt Manufacturer Scan System Permanent
Installation ~ $70k, NR bs2 = Belt Manufacturer Scan System On-site
Personnel required ct = Conveyor Tech Remote Calibrated, Online
24/7 if needed bv = By verification on-site destructive testing of
detected events
16. CONVERT BELT CABLE DAMAGE LEVEL TO A STRAIN CONCENTRATION
Mechanical Model (Ti+1 Ti) = (Ti T/n) 2014 Conveyor Technologies
Pty Ltd. All Rights reserved BreakRubber ShearRubber Shear
CSFStrain Decaylength along cordsStrain Decay across beltMax
CSF
17. DAMAGE ANALYSIS STRESS AT DAMAGE SITE Edge Example (Maximum
Strain) 2014 Conveyor Technologies Pty Ltd. All Rights
reserved
18. DAMAGE ANALYSIS STRESS AT DAMAGE SITE Non-Edge Example (Up
to 30% below Edge Strain) 2014 Conveyor Technologies Pty Ltd. All
Rights reserved
19. 2014 Conveyor Technologies Pty Ltd. All Rights reserved
SAFETY FACTOR GRAPH : Belt will FAIL when SF < 1+ Tmax
(Start)
20. REPAIR DESIGN BASED ON SF ANALYSIS 2014 Conveyor
Technologies Pty Ltd. All Rights reserved
21. TYPICAL REPAIR AND SPLICE SIGNATURES (ST-5400 BELT) 2014
Conveyor Technologies Pty Ltd. All Rights reserved
23. POST-REPAIR SIGNATURE ANALYSIS Basis for Overlap Length
____________________________________________________________ Small
Cables Straight Overlap (Edge Breaks Centre-Breaks 2014 Conveyor
Technologies Pty Ltd. All Rights reserved Parent Belt Cords Break
In-laid Cable 48 inches 5.4 mm 5.4 mm 5.4 mm 2.6 mm 5 Broken Cables
At Edge (5 In-laid cables needed) 5 Non-edge Broken Cables (6
In-laid cables needed) Edge Signature Off-edge Signature
24. BELT LIFE EXTENSION EXAMPLES 2014 Conveyor Technologies Pty
Ltd. All Rights reserved Life Extension factor : LE = A/A1 = No.
Months since Scanning First Commenced No. Months to 1-st Critical
Damage Event A1 is also the time when the belt would have failed if
un-monitored.
25. 2014 Conveyor Technologies Pty Ltd. All Rights reserved
Thank You 6th Annual Conveyors Conference Sept. 22-24, 2014,
Brisbane, Qld