Risk-Oriented Methodology for Creating a 10-Year Shut

Risk-Oriented Methodology for
Creating a 10-Year Shut-Down
Interval
Contact:
Dr.-Ing. Robert Kauer
TÜV Industrie Service GmbH
TÜV Süd Group
[email protected]
Risk
Application Case within the Chemical
Industry
conventional
risk-oriented
Expenditure
1
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
09/2005
5-6 weeks shut-down
of the entire plant
09/2014
internal inspection
hydro-test
2
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
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, ....
§15 (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
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
The Process
Hazard
Identification
Risk
Analysis
Action
Plan
Realization
and Follow-up
Technical
Program
Expert Panel / Responsibilities
RM Process Leader
Management
Preliminary
Analysis
Plant Team
þ Process Leader
þ Operator
þ Inspector
þ Insulation
TÜV Team
þ ROI engineer
þ Inspector
þ Material specialist
þ NDT specialist
Documentation and
Reporting
Decision Making
Equipment Identification
Complexity of Analysis
Client
Benchmark
Plant Hierarchy
Plant
Unit
System
Component
Detailed
Subcomponent
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
CoF/SHE Flow Chart for Leakage to Atmosphere
Calculation Tool for CoF/SHE
Start
Bestimmung des PoF-Wertes (trendable DM Loss of Material)
Determine
Effectiveness Factor EF
History
Evaluate Method and Suitability
of Previous Inspections
EF = f ( Suitabilit y ; Coverage )
Evaluate Coverage of Previous
Inspections
ent
History Assessm
nfidence
o
C
/
s
s
e
n
e
v
ti
c
e
Eff
Evaluate Confidence in the
Previous Inspection Results
e
c
n
a
w
o
ll
A
e
r
u
t
te
a
Fu
R
n
o
ti
a
d
a
r
=
g
e
De
Lif
t
n
a
n
Rem
See Degradation Documents (DD)
for determining
Determine
Confidence Factor CF
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.
Determine
Remnant Life RL
RL =
Determine
Remnant Useful Life RUL
FA
DR
RUL = EF ∗ CF ∗ RL
Determine
Time Frame T
Set Inspection Interval
resulting in Tint
Planning
T = min[T
Future Planning
fidence
n
o
C
/
d
o
ri
e
P
e
Tim
max
Determine the Confidence in
the Future Extrapolation
PoF for Trendable DM
on the Basis of a Usage Factor
End of Time Interval
UFT = T / RUL* FC
; Tint ]
Determine
Future Confidence FC
Determine
Usage Factor Time ( UF T)
UFT =
UF T ≥ 0.4?
yes
UF T ≥ 0.67?
no
1
yes
T
1
∗
RUL FC
UF T ≥ 0.9?
no
2
yes
UF T ≥ 1.0?
no
3
yes
no
4
5
Remnant Life Determination
110
100
6,6337E-03x
y = 5,3690E-05e
R 2 = 9,9620E-01
90
80
Auslastung [%]
usage [%]
70
60
Auslastung (P_L/(1,5xf)) [%]
Auslastung ((P_L+Q)/(3xf)) [%]
50
Exponentiell (Auslastung (P_L/(1,5xf)) [%])
40
30
20
10
0
1950
new 2000
1975
2025
2050
now
2075
Betriebsjahr
2100
2125
2150
future
2175
2200
Measure Planning
Explicit measures (Interval / Methodology / Location / Scope) are planned
on the basis of:
§ The information regarding risk driving systems, components, subcomponents
§ The PoF-value to establish an appropriate interval
§ The risk value to adjust scope and depth of measures
Probability of Failure (PoF)
§ 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
5
2
15
11
2
2
6
4
1
III
0
II
19
15
17
5
2
31
I
86
18
6
0
31
82
17
8
2
Consequence of Failure (CoF)
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
Risk Ranking – Comparison after doing the inspection 2004
Number of Subcomponents with equal risk vs. risk
- leakage heat exchanger and environment -
Number
Anzahl
[-]
[-]
30
Number
Anzahl
Subcomponents [%]
Subkomponenten
[%]
Risk
Risiko
T=5
T=10
1
14
4
2
54
42
3
14
34
4
18
20
5
0
0
25
20
15
10
5
0
T=10
1
2
T=5
3
4
Risikoklasse
Risk
T=5
T=10
5
Betrachtungsevaluation
zeitraum
period
Benefit
09/2005
5-6 weeks shut-down
of the entire plant
09/2004
09/2014
*** internal inspection
** internal inspection
hydro-tests + stress tests
hydro-tests + stress tests
non-intrusive measures