A Guide to Non Destructive Testing of Guy Wires

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1 ZENITH CONSULTANTS 38 Dryden road Loanhead Midlothian EH20 9LZ A Guide to Non Destructive Testing of Guy Wires

2 Introduction: Zenith Structural Access Solutions offers magnetic, non-destructive testing of guy wires as part of our comprehensive range of flare stack inspections. About the instrument: The instrument used to carry out this survey is an Intron Intros MH20-40 magnetic head. This can successfully determine faults within wires ranging from 20 and 40mm in diameter which would ordinarily go undetected by a visual inspection. The head is connected to a data logger, which records the data in real time. For manufacturers details, see Appendix iii. Rigging the Instrument: The instrument is simply clamped to the wire and pulled up and down the guy wire in a controlled manner via a pulley system mounted at the upper support. No proprietary work is required to the guy wire, and no adverse stresses or strains are imposed onto it. How it s done: The survey involves attaching the magnetic head onto the wire, and running it up and down the wire to magnetise it. Once the wire is magnetised, the magnetic head is run up and down a further time to gather the required data, which is stored onto the data logger. The stored information is then downloaded, and analysed using wintros software. By analysing the graphical output from the wintros software, localised faults (LF) and/or metallic loss of area (LMA) can be identified. For full instructions, see appendix ii.

3 What it tells us: These inspections aim to locate the LF s and LMA s, and to determine their severity / magnitude. LF (localised fault): Detects the presence of a broken/defective wire(s), or discontinuity in the rope. LMA (loss of metallic area): Detects loss of sectional area, highlighting possible loss of capacity. What is produced: A detailed report showing the likely locations and suggested severity of faults along the length of each wire. For sample report, see Appendix i.

4 Appendices: i Sample Report ii Instructions for Use iii Manufacturers Brochure

5 Appendix i- Sample Report

ZENITH CONSULTANTS Unit 7 Dryden Vale Bilston Glen

6 ZENITH CONSULTANTS Unit 7 Dryden Vale Bilston Glen Industrial Estate Loanhead Midlothian EH20 9HN XXXXXXX XXXXXXXX Inspection Report Revision C Survey Engineer David Kellyy Prepared By:...John Lambb August 2014 Document Revision Status Rev Details Dated Statuss C Add comparison Tables 13/10 C Author CC Checked SC

7 SECTION 1 - INTRODUCTION 1.0 INTRODUCTION 1.1 In August 2014 Zenith Consultants were engaged by XXXXXX to undertake a survey of the 36-S500B flare stack. The survey was carried out on 03 rd & 04 th August 2014 during the KG TAR shutdown.the report is best read in conjunction with Appendix A, B & C 1.2 The purpose of the survey was to identify and record any defects to the guy wires and termination connections to the flare and to make recommendations for future repair.

8 SECTION 2 DESCRIPTION OF STRUCTURE 2.0 DESCRIPTION 2.1 The flare is 90m high from ground level guyed structure, with 3No anchor blocks located at 120 degrees. Each anchor block has four guy wires supporting the flare. 2.2 The flare has a fixed ladder and staged gantries over the height.

9 SECTION 3 - PROCEDURES AND METHODS 3.0 PROCEDURES AND METHODS 3.1 Access to the head of the flare was achieved using the fixed ladder/gantry arrangement. 3.2 A visual examination of all external parts. 3.3 The Magnetic Inspection was carried out on each guy wire. 3.4 The inspection was carried out using an Intron Magnetic head with Wintros software for assessment of the results. The apparatus uses LMA (loss of metallic area) and LF (local fault) readings to assess the condition of the cable. 3.5 The first section of cable was first magnetised and then used to calibrate the equipment. 3,6 The inspection was carried out using a hoisting arrangement. 3.7 The cable was first magnetised before two inspections were carried out.

10 SECTION 4 - SURVEY RESULTS 4.0 SURVEY RESULTS 4.1 Ground Termination Bases: No evidence of distress to the concrete pile block or soil surrounds. 4.2 Ground Termination Anchors: No evidence of corrosion, distortion or separation from the concrete pile. 4.3 Ground Termination Eyelets and Pins: No evidence of excessive wear, 4.4 Ground Termination Rope Shackles: Shackles appear in good condition and showing no signs of corrosion. 4.5 Ground Termination Turnbuckle: Turnbuckle is in good condition, is fully operational and secure. 70% of adjustment in the turnbuckle is currently in use. 4.5 Stack Termination eyelet arrangement: Good condition, no chaffing or wear. 4.6 Stack Termination Shackle: Good condition. 4.7 Stack Termination Lug: Good condition, no evidence of weld fractures. 4.8 Guy Wire Inspection: Guy wires are in generally good condition, there are however a number of broken wires within some of the cables, but the small number of breaks will have no effect on the stability of the flare. Loss of the metallic coat on the wires over localized areas is evident from the survey data. Refer to Appendix A, B & C for survey results of the guy wires.

11 Verticality & Rope Tension 4.9 The results of the verticality and rope tension are appended (Appendix D) The tension figures in the lower ropes are generally in line with pretension design figures. The recorded information does not reflect the tension values obtained in the previous year s measurements, the recorded information for this year is consistently higher than the 2009 readings The variation in readings could be due a variation in site wind speed, wind direction, gusting, site temperature, operating temperature etc. If the site variables are low during one survey, a relatively modest increase of the variables in the next survey could result in a threefold increase in load In the absence of the original calculations Zenith have adopted a comparison against of the tension figures suggested by Guydes, (Guydes being one of the leading software packages for the design of guyed stacks) For the purpose of comparison, good practice suggests guy stacks are typically set at pretension of only 6% to 12% of the breaking strength due to the hot gases flowing into the stacks The ropes are within these guidelines but remain marginally over tensioned when compared to the pre-tension design data on record. It would be normal practice to only tension ropes rather than slacken ropes in a scenario where the towers have performed with out fault and show no sign of distress In conclusion the ropes would be re-examined within 12 months recording all tolerances at site level including temperature and wind speed The verticality of the structure is marginally out with tolerance in the lower two positions. No correction has been made at this time based on the upper levels of the flare stack being within tolerance. It was determined that any adjustment at this stage would compromise the overall results and therefore no action undertaken.

12 SECTION 5 - DISCUSSION AND RECOMMENDATIONS 5.0 DISCUSSION AND RECOMMENDATIONS 5.1 The flare guy wires and termination points should be inspected at regular intervals. 5.2 The flare remains serviceable under current operating conditions. 5.3 The flare guy wires are in serviceable condition and should be re-inspected during the next shutdown in Although there are localized areas where the metal coat to the wire has thinned or has been removed, there is no requirement for any repair work to be carried out at this time. 5.5 A magnetic inspection should be carried out at the next shut down in The result of which should be read alongside this survey to give a rate of deterioration of the wires. 5.6 Zenith remain satisfied that the guy ropes and the flare stacks are operating within tolerance as the thermal expansion due to hot gases in this instance is limited to the tip of the stack and not throughout the full length hence the tension in the wires can approach the 20% to % generally used for transmission towers restrained by guys. 5.8 The verticality of the tower should be checked at regular intervals (not exceeding 12 months) and where tension has relaxed every effort made to correct the verticality to within the BSEN standards without compromising the overall tolerances.

13 SECTION 6 APPENDICES APPENDICES A- Elevation A guy wires B- Elevation B guy wires C- Elevation C guy wires D- Verticality & Rope Tension E- Comparison Tables

14 APPENDIX A- ELEVATION 'A' GUY WIRES

15 LF trace, mv LF trace, mv LF trace, mv LF trace, mv

16 APPENDIX B - ELEVATION '8' GUY WIRES

17 LF trace, mv LF trace, mv LF trace, mv LF trace, mv

18 APPENDIX C ELEVATION C GUY WIRES

19 LF trace, mv LF trace, mv LF trace, mv LF trace, mv

20 APPENDIX D - VERTICALITY AND ROPE TENSION

22 APPENDIX 'E' - COMPARISON TABLES

23 Client Structure Ineos Manufactuing (Scotland) Ltd Flare B 36 S 500 B Height D1 D2 Max. Allowable Resultant Result mm mm mm mm Total MM2 MM 1 1 (Lower) FALSE FALSE OK 4 4 (Upper) OK FALSE FALSE * D1 = Direction 1, D2 = Direction 2 Readings are based on 'Latch & Batchelor' Steel Wire Ropes Booklet for General Purpose Ropes to BSEN with a Steel Core Grade 1770 N/MM2 and should only be used as a guide. Where a direct comparsion can not be made the reading (i.e dia/construction) the next lower performing wire should be used. Comparison with the original design / construction should be completed, wherever practical. Rope No Position Diameter Measured Load (Kn) Theoretical MBL (Kn) % of MBL 1 A B C A B C A B C A B C Cross Check Information Dia MBL MBL 6% Lower Theoretical 9% Average Theoretical 12% Upper Theoretical 20% Cold Structure 40% Upper Limit MM Rope Type Kn t Kn t Kn t Kn t Kn t Kn t 18 6X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X X19, 6X36, 6X

24 Appendix ii -Instructions for Use

27 Appendix iii- Manufacturers Brochure

Status: Issue 08 Date: 18/10/17 Reference: Lifting Operations and Lifting Equipment Regulations 1998 Regulation 9

GUIDANCE IN-SERVICE INSPECTION PROCEDURES Number: MLCC 03 Prepared by: MACHINERY LIFTS AND CRANE COMMITTEE Status: Issue 08 Date: 18/10/17 Reference: Lifting Operations and Lifting Equipment Regulations