Risk-Oriented Methodology for Creating a 10-Year Shut-Down Interval. Risk. Application Case within the Chemical Industry

Transcription

1 Risk-Oriented Methodology for Creating a 10-Year Shut-Down Interval Application Case within the Chemical Industry Contact: Dr.-Ing. Robert Kauer TÜV Industrie Service GmbH TÜV Süd Group robert.kauer@tuev-sued.de Risk Expenditure conventional risk-oriented 1

2 The Situation (BetrSichV = German ISI-Code) 15 (1) Der Betreiber hat die Prüffristen der Gesamtanlage und der Anlagenteile auf der Grundlage einer sicherheitstechnischen Bewertung zu ermitteln. The operator of a plant has to determine inspection intervals for the entire plant and its components on the basis of a safety related assessment. 15 (9) Bei Druckbehältern... müssen Prüfungen von ZÜSen durchgeführt werden - innere Prüfung spätestens nach fünf Jahren und - Festigkeitsprüfung spätestens nach zehn Jahren. For pressure vessels... inspections have to be performed by ZÜS organisations - internal inspections latest after 5 years - strength tests latest after 10 years 09/2004 internal inspection hydro-test 09/ weeks shut-down of the entire plant 09/2014 internal inspection hydro-test 2

3 The Task Creation of an inspection philosophy to avoid the big shut-down after 5 years and run into a 10-year period without any shut-down due to inspection requirements 3

4 The Loophole 15 (10) Bei äußeren und inneren Prüfungen können Besichtigungen durch andere geeignete gleichwertige Verfahren und bei Festigkeitsprüfungen die statischen Druckproben durch gleichwertige zerstörungsfreie Verfahren ersetzt werden,... External or internal visual inspections can be substituted by other adequate measures and regarding the strength test the hydro-test can be substituted by adequate NDT-methods, (17) Die zuständige Behörde kann die... genannten Fristen im Einzelfall 1. verlängern, soweit die Sicherheit auf andere Weise gewährleistet ist, oder 2. verkürzen, soweit es der Schutz der Beschäftigten oder Dritter erfordert. The regulator can case by case 1. extend the periods, if the safety can be guaranteed in an adequate manner 2. reduce these periods, if it is required to guarantee the safety for staff and externals Demands are related to the consequences for staff and public and are related to the probability of the corresponding failure. 4

5 The Track Demands are related to the consequences for staff and public and are related to the probability of the corresponding failure. Definition of RISK (PoF x CoF) Risk-Oriented Methodology RIMAP Framework and Procedures

6 The Process Management RM Process Leader Preliminary Analysis Hazard Identification Risk Analysis Action Plan Realization and Follow-up Technical Program Expert Panel / Responsibilities Plant Team Process Leader Operator Inspector Insulation TÜV Team ROI engineer Inspector Material specialist NDT specialist Documentation and Reporting Decision Making

7 Equipment Identification Complexity of Analysis Client Benchmark Plant Hierarchy Plant Unit System Component Detailed Subcomponent

8 The Hierarchy HExxxx shell side shell course leakage SHE shell-nozzle leakage SHE compensator leakage SHE... tube side tube bundel leakage HE dished head/inlet leakage SHE dished head/outlet leakage SHE

9 CoF/SHE Flow Chart for Leakage to Atmosphere

10 Calculation Tool for CoF/SHE

11 Start History Bestimmung des PoF-Wertes (trendable DM Loss of Material) Evaluate Method and Suitability of Previous Inspections Evaluate Coverage of Previous Inspections History Assessment Effectiveness / Confidence Evaluate Confidence in the Previous Inspection Results Determine Effectiveness Factor EF EF = f ( Suitabilit y ; Coverage Determine Confidence Factor CF Determine Remnant Life RL Determine Remnant Useful Life RUL RUL = EF CF RL ) See Degradation Documents (DD) for determining Future Allowance FA Degradation Rate DR For determining the Remnant Life, the applicability and the physical background of the method itself must be considered by using appropriate safety margins. Remnant Life = FA RL = DR Future Allowance Degradation Rate Planning Set Inspection Interval resulting in T int Future Planning Time Period / Confidence Determine the Confidence in the Future Extrapolation Determine Time Frame T T = min [ T T ] ; max int Determine Future Confidence FC Determine Usage Factor Time ( UF T ) T 1 UF T = RUL FC PoF for Trendable DM on the Basis of a Usage Factor End of Time Interval UF T = T / RUL* FC UF T 0.4? yes UF T 0.67? yes UF T 0.9? yes UF T 1.0? yes no no no no

12 Remnant Life Determination y = 5,3690E-05e 6,6337E-03x R 2 = 9,9620E usage [%] Auslastung [%] Auslastung (P_L/(1,5xf)) [%] Auslastung ((P_L+Q)/(3xf)) [%] Exponentiell (Auslastung (P_L/(1,5xf)) [%]) new now future Betriebsjahr

13 Measure Planning Explicit measures (Interval / Methodology / Location / Scope) are planned on the basis of: The information regarding risk driving systems, components, subcomponents The information regarding acting damage/deterioration mechanisms, remnant life and the confidence level achieved (regarding material, loading, and defect situation), through which adapted and adequate measures can be selected The PoF-value to establish an appropriate interval The risk value to adjust scope and depth of measures Probability of Failure (PoF) III II I Consequence of Failure (CoF)

14 Example HExxx: Additional testing measures Additional testing at the inspection 2004 Tube Side: Liquid penetrant testing of tube sheet (inlet) eddy current testing of heat exchanger pipes (random sample, preferably at OD) Shell Side: Liquid penetrant testing of junction nozzle and vessel wall, expansion joint UT of vessel wall thickness on the lower part of the vessel wall and at the junction of nozzle and vessel wall Additional testing (must be done until 2009) Tube Side (at shutdown): Liquid penetrant tube sheet eddy current testing of heat exchanger pipes (random sample, preferably at outer diameter). If possible by testing through inlet nozzle or disassembly of heads. Shell Side Liquid penetrant testing of junction nozzle and vessel wall, expansion joint, UT of vessel wall thickness on the lower part of the vessel wall and at the junction of nozzle and vessel wall

15 Risk Ranking Comparison after doing the inspection 2004 Number of Subcomponents with equal risk vs. risk - leakage heat exchanger and environment - Number [-] Anzahl [-] Risikoklasse Risk 4 5 T=5 T=10 Number Anzahl Subkomponenten Subcomponents [%] Risiko Risk T=5 T= Betrachtungszeitraum evaluation period T=5 T=10

16 Benefit 09/ weeks shut-down of the entire plant 09/2004 *** internal inspection hydro-tests + stress tests 09/2014 ** internal inspection hydro-tests + stress tests non-intrusive measures