© ABB Group February 20, 2012 | Slide 1
CSC 2011 Life Extension for Ageing Equipment
Neil Henry, ABB Consulting, September 2011
© ABB Group February 20, 2012 | Slide 2
Life extension for ageing plant
§ Why is it necessary?
§ What is required for process equipment?
§ A different approach from existing codes and methods
§ Examples
§ Typical result from studies
§ Learning from the work carried out
© ABB Group February 20, 2012 | Slide 3
Asset Life - issues faced by production operations
CHANGING PRODUCTION REQUIREMENTS
Different production methods, constituents and profiles
CHALLENGING WORLD ECONOMIC CLIMATE!
Operate beyond original design life
Run for cash
New plant build scale rising
1970’s 1990’s 2010’s 2030’s 2050’s Investment Justification
AGEING EQUIPMENT Pressure from Regulators
CHANGES to Engineering Standards
© ABB Group February 20, 2012 | Slide 4
Why is it necessary? Process safety in older plant
Why is age important – “what is an expected service life?”
§ HSE concern resulted in Research Report (RR)509, 2006
§ Further work leading to RR823 published 2010, concluded
§ “Ageing” influenced over 30% of equipment failures
§ …HSE have to consider Operators safety justification for continued use of ageing plant
§ OSHA – National Emphasis Programs in refinery and chemical (for mechanical integrity)
It is far more than a compliance issue – equipment reliability is an essential business requirement: confidence in assets
© ABB Group February 20, 2012 | Slide 5
Asset categories v UK legislation
Pressure Energy
Hazardous Fluids Business
Critical
Pressure Systems Safety Regulations
(PSSR)
COMAH, IPPC, PUWER
Non-critical equipment (remainder)
Corporate Governance
© ABB Group February 20, 2012 | Slide 6
OSHA CFR 1910.119 (Process Safety Management)
Quotes from standard
!! effective process safety management program requires a systematic approach to evaluating the whole process
!! employers need to develop the necessary expertise, experiences, judgment and proactive initiative within their workforce to properly implement and maintain an effective process safety management program
!! that the design and construction along with the testing, inspection and operation are still suitable for the intended use. Where the process technology requires a design which departs from the applicable codes and standards, the employer must document that the design and construction is suitable for the intended purpose.
© ABB Group February 20, 2012 | Slide 7
Process
Safety
Integrity
Management
There are many common aspects
Many benefits result from an Integrated approach to Safety and Integrity
© ABB Group February 20, 2012 | Slide 8
Why does equipment fail? Lab Data.
No of Failures
0
5
10
15
20
25
30
35
40
Co
rro
sio
n
SC
C
Fa
tigu
e
We
ldF
ailu
re
Ero
sio
n
Bri
ttle
fra
ctu
re
Me
cha
nic
al
Fa
ilure
Cre
ep
Ove
rhe
atin
g
Ove
rP
ress
ure
We
ar
No of Failures
© ABB Group February 20, 2012 | Slide 9
Identifying root causes
0
10
20
30
40
50
60
70
80
Operation Design flaw MaintenanceError
FabricationDefect
Failed repair Other
Series1
© ABB Group February 20, 2012 | Slide 10
Failure of process plant
!! There are very few failures reported on pressure equipment
!! Statistics suggest failure rates of 1x103 to 1x104 yrs:
!! But what level of ‘failure’? (deterioration, leak, major loss)
!! When could failure occur?
!! This year, next!..in 5 years or more
!! Most failure statistics exclude corrosion damage
Objective is Avoiding unplanned ‘failure’ - production impact
© ABB Group February 20, 2012 | Slide 11
Ageing plant - The ageing stage
• Approaching design limits • Evidence of significant accumulated damage • Changes in process use • Repairs, refits, modifications • Deficiencies in systems and skills
Acc
umul
ated
Dam
age
Time
Initial Operation
Mature Stage
Ageing Stage
Terminal Stage
Ref: HSE RR 509 – Plant Ageing – Management of equipment containing hazardous fluids or pressure
© ABB Group February 20, 2012 | Slide 12
What affects asset life? Understanding the challenge
Design
Construction
Operation
Maintenance
Inspection
Modifications
Suppliers
Asset life factors across the life cycle
Quality of the original fabrication and installation
Obsolescence of equipment
Operating within original design limits
Knowledge of equipment condition e.g. Inspection of static equipment or condition monitoring of rotating equipment
Change of equipment or operations that negates original design
Maintaining equipment in ‘fit for service’ condition Quality of spare parts and repairs
Design quality - Life-limiting factors assumed at design stage
© ABB Group February 20, 2012 | Slide 13
Life extension - challenges
!! Application of life extension practices change to equipment and operating regimes,
incremental over time
!! Not simply fatigue or creep life
operating cycles and / or time related factors not in design (fatigue or thermal)
!! Progressive corrosion model for life & inspection
time of initiation of corrosion
operational change over time
!! Condition Monitoring systems
knowing what to monitor?
!! Primarily containment of high hazard substances – not pressure
© ABB Group February 20, 2012 | Slide 14
Asset life extension
How to understand remaining Asset Life?
Remnant Life
Asset Life
© ABB Group February 20, 2012 | Slide 15
Process change examples
§ Peak load operating – eg power plants
§ Product demand cycles
§ Overnight shutdowns
§ Week-end shutdowns
§ Product grade change
§ Feedstock change
§ Process optimisation – temperature changes
© ABB Group February 20, 2012 | Slide 16
Ti centrifuge suffering wear
§ New grades of product contained higher residual acid and increased abrasion
§ Spare scroll installed when required - repair was carried between shutdowns
§ Limited management of repair – no evaluation of damage extent
Actions taken
§ Evaluation & application of surface coating to scroll tips to extend life
Wear & Corrosion of centrifuge scrolls
© ABB Group February 20, 2012 | Slide 17
Life extension “Management Cycle”
Corporate production planning
Business strategy
Prioritisation of assets
Condition & life
assessment
Data gathering
Project Delivery
Project priority
evaluation
Project Scoping
Asset Life Actions
Asset Sustenance plan
© ABB Group February 20, 2012 | Slide 18
Typical results of Ageing Plant Study
ALS Category
7% 1%11%
73%
8%
A
B
C
D
E
Items need to be replaced within next 20 years
Items need major repairs within next 20 years
Items need minor repairs within next 20 years
Items can continue to be operated for the next 20 years
Items need further evaluation
© ABB Group February 20, 2012 | Slide 19
Deterioration Mechanism(s)
Over required lifetime
£ £ ££££ £££ ££
Not significant Minor
Major
No routine maintenance –
“operate to failure”
Routine maintenance
Minor repair Significant
repair
Replacement
Interpreting the results financially
© ABB Group February 20, 2012 | Slide 20
Typical study output. Spend map is predicted
20062007
20082009
20102011
20122013
20142015
20162017
20182019
20202021
20222023
2024
2025
2026
Total
0
10000000
20000000
30000000
40000000
50000000
60000000
Total
Total
Sum of Cost
Year Required
Estimated Investment per Year (overall)
© ABB Group February 20, 2012 | Slide 21
Asset life extension – part of an integrated study
Process Hazard Review
SIL
Asset Life Studies Criticality and
Management of Risk
Training, Coaching
and People Development
Total Plant Reliability
Effective Turnaround Management
RBI+ and RCM
Specialist Technical
Consultancy
Rotating & Machines Electrical
Control Instrumentation
Civil & Structural Vessels Piping
Fired Equipment Materials Process
© ABB Group February 20, 2012 | Slide 22
Example of top down asset life assessments
Impact of Deterioration Mechanisms
Normal Design Life
Assessed Asset Life
Heat Exchanger
40 years plus
Service & process
Corrosion fretting
20 years or less
Original Design Standards
Best Practice
Maintenance Practices
Inspection Methods & History
Operating Practices
Environmental Conditions
Process Pump
30 to 40 years
Corrosion or Erosion
10 years or less
© ABB Group February 20, 2012 | Slide 23
Asset life extension
Effective & efficient application:
§ Criticality or vulnerability study
§ Identified investment required
§ Actions necessary to maintain integrity
§ Achieving Safety Standards
§ Sustain or achieve operating performance
§ Meet future production requirements
§ In the short term (typically up to 5 years)
§ In the longer term (typically 10 to 20 years)
© ABB Group February 20, 2012 | Slide 24
Conclusion – life extension to avoid this!
Humber Refinery 2001 Texas City 2005
Piper Alpha 1988 Pembroke Refinery 1994
Piper Alpha 1988
Texas City 2005
Pembroke Refinery 1994
Humber Refinery 2001
© ABB Group February 20, 2012 | Slide 25