Optimizing valve maintenance using condition analysis
IPPTA seminar 17th July, 2014
Speaker:
Jarkko RätyDirector, Services, Business Solutions
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Typical Maintenance Issues
• Unexpected failures− Production breaks cause loss of
revenue
− Safety and environmental issue
• Lack of targeted maintenance− Unnecessary maintenance costs
− Unnecessary risk of damage
− Are the right issues tackled ?
• Typical Performance Statistics− 30 % of controls increases process
variability
− 10-30 % of controls in Manual
− 30 % of valves with problems
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Traditional ways of selecting Valves for shutdown maintenance
• Certain Critical always
• Operator indications
• Grouping for each shutdown
• No actions if by-pass available
• Run to failure (=no actions)
Typically one rule is not directly followed, reality is more like combinations of the rules
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Operational History
Making a maintenance recommendationDevice history and present condition defines the action
ConditionAnalysis
Service History
Maintain in Place
Remove & Maintain
OK
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Maintenance decision makingDefining the actions is a continuous process
Prioritize
Analyse
PlanRepair
Report
Filter
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Maintenance based on known conditionMay reduce valve shutdown cost by up to 50 %
Field Work• Removal, reinsertion• Lifting, scaffolding• Transportation
Traditional Shutdown
Maintenance• Refurbishment• Spare parts• Testing
Condition Analysis• Visual Inspection• Diagnostic Analysis• Devices Testing
Adjustments• Calibrations• Preventive Actions• Tightening
Shutdown with Condition Analysis
70 % reduction in Field Work cost30+ % reduction in Maintenance costs
Typically30% valves require no action40% valves can be maintained in place30% valves require removal for maintenance
Up to 50 % reduction in Shutdown
Condition AnalysisKnown device conditions – makes maintenance intelligent
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Various intelligent analysis tools and methods are available to reveal field device conditions.
The suitable tools are sellected according to the existing installed device base and control system infrastructure.
Intelligent Maintenance
Device analyses are scheduled according the criticality. The known device conditions and criticality are used to prioritize daily maintenance actions.
Intelligent Shutdown
Devices are sellected for maintenance based on known device conditions and unnecessary maintenance can be avoided.
Condition Analysis ToolsRemote performance and diagnostics analysis
Smart Device Check
One-shot diagnostic analysis of large amount of devices for Shutdown planning purposes
Smart Device Monitoring
Continuous diagnostic analysis architecture for Maintenance and Shutdown planning
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Control Device Monitoring
Use the loop monitoring system to identify underperforming valves and identify probable root causes
Control Device MonitoringAn example: Detecting oscillations caused by a sticky valve
1. Graphical view to illustrate Valve Health
2. Deeper analysis reveals valve stiction
3. Process trend confirms typical sticky valve behavior- Process Value remains steady despite of changes in
Control actions until it moves
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SP = SetPointPV = ProcessValue (a flow meter)
CO = Control (to valve)
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ENGHIS
PCS
OPC
Contol Loop Monitoring
Smart device diagnostics utilizationAn example: Detecting air leakage in valve actuator
1. Condition Monitoring alarms malfunction
2. Remote analysis reveals excessive air consumption
- Gradual chance in Spool Valve Position
3. Actuator membrane failure (a hole) was discovered in devices maintenance
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Utilizing diagnostic information:
• Trouble Shooting (one device at the time)• Analysis of 10’s or 100’s of devices• 24/7 monitoring
Condition Analysis ToolsPortable testing devices
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Control Valve Testing
Testing of valve condition with portable testing system for Shutdown and Maintenance planning
Safety Valve Testing
Testing of safety relief pressure valves in process to determine if they are operating correctly at correct pressure setting
Valve Leak Testing
Testing of valves in process to determine if they are leaking when shut
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Control Valve TestingDetecting sticky valve by ramp movement
PC
Measurement system
1. Testing system connection to valve
2. Attachment options for external potentiometer
3. Testing results revealed valve sticking - while leaving the seat
- in the upper half of the stroke
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Valve Leak TestingLeakage detection and leak rate estimation
1. Acoustic measurement on predefined spots of valve assembly
2. A leak detected by acoustic signal
3. Estimation of leakage rate
4. Reporting devices conditions and recommended actions
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GAS LEAK ESTIMATIONContact: JR
COMPANY: Customer LOCATION: Site Date: 13/05/2013Valve Signal Pressure Inlet Gate Ball Leak Fluid LossI.D. Level Difference Size Valve Valve Rate Density Estimation
(dB) (bar) (ins NB) (y/n) (y/n) (l/min) (kg/m 3̂) (Tonnes/yr)PV-1280601A 23 13 2,0 N Y 0,7 1,2 0,46PV-1280601B 32 13 6,0 N Y 4,8 1,2 3,01PV-1290501 28 21 4,0 N N 3,5 1,25 2,29PV-1310702 18 5 1,0 N N 0,5 0,8 0,21PV-1470601A 17 9 5,0 N Y 0,9 1,25 0,62PV-1470601B 22 9 8,0 N Y 2,4 1,25 1,61
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A leak detected
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Safety Valve TestingTesting verifies pressure setting of safety valves
1. Setting up of testing system
2. Automatic testing run
3. Test report and pressure setting certificate with Maintenance recommendations
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Condition Analysis
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Analysis for different field device types
Device Type Vendor independent Vendor dependent Continuous / networked Off-line (portable) Bulk analysis
Sensors • Control Device Monitoring
• Smart Device Monitoring
Valves
• Control Device Monitoring
• Smart Device Monitoring
•Control Valve testing
•Valve leak testing
•Safety valve testing
• Smart Device Check
Suzano BA Shutdown 2012, Brazil Company profile
Suzano- 2nd largest eucalyptus pulp producer in the world (8th in market pulp)- Pulp production costs is one of the lowest in the world- Six industrial units in Brazil
Suzano BA (Mucuri)- Pulp production 1.540 ktons yearly- Uncoated paper 250 ktons yearly
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Suzano BA Shutdown 2012 Results through Condition Analysis
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232 pcs
Preliminary list for
valve maintenance
153 pcs
Condition analyses
bySmart Device
Check
79 pcs
Visual inspectionand
Operational tests
22 pcsMaintenance
131 pcsOK
44 pcsMaintenance
35 pcsOK
66 pcs Maintenanc at
workshop
93 pcsAdjusment and
preventive actionon pipeline
73 pcsNo action
Customer Request Testing Plan Test Results Shutdown Actions
Shutdown time Shutdown 11 daysStart-up 3 days
Manning 33 Metso Professionals 2 Partner Professionals
for electrical actuators
Shutdown activities• 66 pcs maintenance of automatic valves• 7 pcs maintenance electric actuators • 93 pcs positioners adjustments and preventive tasks • 5 pcs extra activities requested by Suzano.
Suzano BA Shutdown 2012Maintenance Execution
Planning & Execution
• Activities included in the master schedule
• Monitoring the progress of activities
• Implementation of maintenance actions according to company procedures
Smart Device Check
Maintenance Planning ShutdownStart-
upVisual & Operational
CheckingOperational &
Maintenance History
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Suzano BA Shutdown 2012Direct reduction in maintenance costs 44 %
100 %
Preliminary Estimation
Condition Analysis• Visual Inspection• Diagnostic Analysis• Devices Testing
Adjustments• Calibrations• Preventive actions• Tightening
56 %
Actual
44 % reduction in Maintenance costs
Results31% valves required no action40% valves adjusted in place29% valves required removal for maintenance
50 + % reduction in Shutdown costs when Field Work taken into account
Field Work• Removal, reinsertion• Lifting, scaffolding• Transportation
Maintenance• Refurbishment• Spare parts• Testing
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