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Fieldbus Overview India
© 2007 Fieldbus Foundation
Fieldbus FoundationFieldbus Foundation – India Marketing Committee
Technology Event
ISA EXPO – 2007,
Pragati Maidan, New-Delhi
Fieldbus Overview India
© 2007 Fieldbus FoundationMFX: May 2007
3© 2007 Fieldbus Foundation
What is ‘Performance’ ?“the act of performing; of doing something successfully; using
knowledge as distinguished from merely possessing it”
Therefore ‘Overall Performance’ in relation to a plant with Valves, maybe could be defined as:-
‘‘the act of using our knowledge (and experience) to operate and the act of using our knowledge (and experience) to operate and maintain the valves in a way that improves the success of the maintain the valves in a way that improves the success of the plantplant’’
4© 2007 Fieldbus Foundation
Overall Valve Performance‘‘the act of using our knowledge (and experience) to operate and mthe act of using our knowledge (and experience) to operate and maintain the aintain the valves in a way that improves the success of the plantvalves in a way that improves the success of the plant’’..
This is a reasonable and fair definition – as our main interests are to:-Run the plant profitably – and therefore also keep our costs as low as
possible.
Make a good product of predictable, consistent Quality and Quantity.
Ensure Health and Safety – avoiding accidents or failures thatcause accidents.
Reduce the risk of unplanned shut-downs and extra work.
5© 2007 Fieldbus Foundation
Following this logic, in order to successfully…Run the plant profitably – and therefore keep our costs as low as possible.ANDMake a good product of predictable and consistent quality and quantity.ANDEnsure health and safety – avoiding accidents or failures that cause accidents.ANDReduce the risk of unplanned shut-downs and extra work….
Then knowledge, experience and investigation is needed.Then knowledge, experience and investigation is needed.
But where does this come from ? What shape does this take ?It feels like a huge task………
6© 2007 Fieldbus Foundation
But the solutions are available and are around us - Some are obvious and familiar and some are not so….
Choosing the right Valves for the application.This is obvious and familiar and yet how often do we see the wrong Valves selected for an application !
Following the recommended maintenance procedures and schedules.Again an obvious statement, but some plants are more dedicated to maintenance and safety than others.If you have any doubts here and think this is unlikely, just think of the news such as the problems and resultant court action at BP. …..
7© 2007 Fieldbus Foundation
From Times OnlineAugust 15, 2006BP sued over Prudhoe BayBy Michael Herman and Agencies
Senior managers at BP are facing legal action in the US accusing them of breaching their duty to shareholders by allowing equipment at the Prudhoe Bay oil field in Alaska to deteriorate. A lawsuit filed in New York yesterday on behalf of a private investor claims that senior executives at the company, including the chief executive, Lord Browne of Madingley, failed to carry out essential repairs before the oil field, America’s largest, had to be partially shut-down. The closure caused significant disruption to US oil supplies and caused BP shares to fall."Despite their awareness of the dangerous effect of the corrosion in the pipeline, defendants repeatedly failed to fund the work necessary to correct the problem," the suit alleged. It did not specify an amount sought in damages.A spokesman for BP declined to comment, but the company has previously said it is expecting a repair bill of around $200 million (£106 million) to fix the field.
http://business.timesonline.co.uk/tol/business/law/corporate/article609577.ece
8© 2007 Fieldbus Foundation
For the Athlete or Footballer, we need to ensure:-That there is a natural potential for the sport. There are no illnesses or physical damage.The correct training is followed.We use the best and most appropriate shoes, clothing, bats, balls
or other necessary equipment.There is a good, healthy diet.Get a good amount of rest and sleep.A positive mental attitude.Emotional well-being.The development of Confidence.An excellent game-plan.
So if we want to ensure safe and successful operation, we could think about the following analogy.
Running Valves on a plant can be likened to the careful training of an Olympic Athlete or a World-Class footballer.
9© 2007 Fieldbus Foundation
Ignore illnesses and physical damage.Not bother to train.Use cheap and substandard shoes, clothing, bats, balls or
other necessary equipment.Eat ‘junk’ food.Think only about failing and just ‘getting by’.Feeling sad and low.Not bother to effectively plan.
What you definitely would NOT do is:-
And of course this kind of approach is not good for improving And of course this kind of approach is not good for improving Overall Valve and plant performance either !Overall Valve and plant performance either !
10© 2007 Fieldbus Foundation
The analogy is close to the situation of a Valve on a plant because:-For the Athlete or Footballer, we need to ensure:- For Overall Valve Performance, we need to ensure:-
That there is a natural potential for the sport. >>
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We select the right Valve and Positioner for the job.
There are no illnesses or physical damage. The Valve and Positioner are in good condition.
The correct training is followed. We operate them in the correct way.
We use the best and most appropriate shoes, clothing, bats, balls or other necessary equipment.
We utilise the right tools and prognostic systems.
There is a good, healthy diet. We ensure a clean air supply and an appropriate service.
Get a good amount of rest and sleep. The valve has a regular maintenance schedule.
A positive mental attitude. Being pro-active in using the most advanced tools.
Emotional well-being. Trust in our own abilities and training.
The development of Confidence. There is confidence in the abilities of the suppliers.
An excellent game-plan. The plant is well-designed, controlled and operated.
11© 2007 Fieldbus Foundation
Consider this…..
Are you really concerned about the health and performance of your valves ?
12© 2007 Fieldbus Foundation
Surveys tell us thatSurveys tell us that…… Sadly, Users are not concerned enoughSadly, Users are not concerned enough
The majority of Users are only concerned with Critical valvesTypically <20% of installed base
Many control loops are left in manual.In case the valve is not in good shape.
There isn’t a Pro-active approach.The current philosophy is: “If it isn’t broken, don’t fix it”
There is a slow take-up of new technologies and advanced prognostic tools.
13© 2007 Fieldbus Foundation
As previously stated, the Top reasons to be concerned with Control valves are:-
The mechanical nature = Which means a Higher failure rate.They are exposed to harsh processes and environments.To maintain and improve plant safety.To reduce operational and maintenance costs.
e.g. air consumption, repairs, shut-down costs, eliminate failure risk etc.
The potential for increased process efficiency / product yield.The possibility for increasing process ‘Up-time’.
Control valves are one of the Most Expensive items of plant equipment to maintain.
14© 2007 Fieldbus Foundation
The solutions are available and are around us - Some are obvious and familiar and some are not so….
Having good information from our technology – in order to ‘See’ what is happening in our process.
Using alarms and warning systems that give us a prediction of a problem/failure/plant upset.
Reduce the risk of unplanned shut-downs and extra work
Diagnostics and more importantly ‘Prognostics’ gives us the essential tools for this –but who uses them ? Who understands them ?Too often they are seen as expensive, time-consuming extras rather than highly useful and beneficial tools.
Definition: PrognosisPrognosis (literally fore-knowing, foreseeing) is a medical term denoting the doctor's prediction of how a patient's disease will progress, and whether there is chance of recovery – seeing ahead to predict the outcome before it happens.
15© 2007 Fieldbus Foundation
So what may go wrong with a control valve and reduce overall performance ?Actuation
Broken SpringAir leakage (diaphragm, tubing)Bench Range Calibration
Abnormal FrictionPackingGuides / Trim
PositionerLinkagePneumatics (I/P, Relay)Calibration / PerformanceLoss of air supply
Trim Wear (plug/seat)Seat leakageBody damage
Packing WearFugitive EmissionsStem Wear/CorrosionSafety Hazards
Application ProblemsCavitation / FlashingNoiseVibration
16© 2007 Fieldbus Foundation
Some of the key points we have identified so far in improving overall performance are:-
The importance of selecting the right Valve and Positioner for the job.- This seems easy, but are all Positioners created equal ?
Making sure the Valve and Positioner are in good condition.- But how do we effectively and yet easily monitor this on a day-to-day basis without lots of extra work ?
We operate and monitor them in the correct way.- Wouldn’t it be good if we had automated and simple to understand notification or warning if something was wrong ?
We utilise the right tools and prognostic systems. - To get the best advantages from our technology.
The valve has a regular maintenance schedule.- But without unnecessary work, cost, effort or delays to production.
17© 2007 Fieldbus Foundation
What do we need ?To have good Valve performance, as a well as a good Valve we need a good Positioner.
But what are the characteristics of a good Positioner ?
It must be Reliable.It has to be Accurate.Its performance must be Consistent/Repeatable.Easy to set-up and use.Provides additional Intelligent features – such as diagnostics. Easily integrates with your DCS/Control strategy.Be ‘Fit & Forget’.
18© 2007 Fieldbus Foundation
It is the needs of the User and the Plant that determine the final characteristics of a good Fieldbus Positioner.
19© 2007 Fieldbus Foundation
More extensive features, such as diagnostics represent the key area that helps with overall performance improvements – by identifying an impending problem before it becomes serious and has an impact on the plant.
20© 2007 Fieldbus Foundation
One aspect of improving performance – by reducing Plant Down-time - is the ability to quickly fix any fault that might occur. A Fieldbus Positioner designed with a small number of modular parts greatly assists in this task.
21© 2007 Fieldbus Foundation
The key advantages of adding a Fieldbus Positioner:-
• It creates an information portal to monitor valve health.
• You can see exactly what is going on.
• Remotely Access the Control Valve.
• Improve Control Valve Performance.
• Monitor The Health Of Valves Online.
• Assess Mechanical Health Using Diagnostics.
• You can see if you are using the valve in the optimum way and if it is correct for the application.
22© 2007 Fieldbus Foundation
Controller Range = 0 - 30K#/HrSetpoint=16.3623 K#/hrPV= 16.4517 K#/hr
Inlet Pressure = 3600 PSI Outlet Pressure = 3400 PSI
Dynamic Matrix ControlMain Syngas Feed, Tag: X0F102Valve: 2” 41000 Series (ATO)Cv = 20 , Stroke = 0.8”3 - 15 # Spring Actuator (ATC)50 # Air Supply
Dynamic Stem Load RangeControl = 160 psiSeated = 3568 psi
Dynamic Stem Control AccuracyControl = 0.4768 psiSeated = 10.623 psi
Dynamic Control Ratio = 335.8:1
Stem Position Resolution = +/- 0.002384”(1/2 thickness of a human hair)
Installed Total Loop Precision = +/- 0.298%
Using Reliable and Highly Accurate Fieldbus technology enables you to increase the Total loop accuracy
23© 2007 Fieldbus Foundation
After installing a high quality Fieldbus Positioner – it is possible to achieve something in the order of a 53% reduction in the standard deviation from the set-point.
24© 2007 Fieldbus Foundation
Installed Valve Performance
+ / - 55 Thousandths of a Percent
Looking more closely…….
25© 2007 Fieldbus Foundation
The Performance gains are also significantly enhanced within a Fieldbus Positioner through the complicated software algorithms.
These are used to simplify otherwise difficult tasks that would be tedious, time-consuming and frustrating to set-up manually.
Fortunately, this is all handled automatically through the software and set-up wizards – making life easier, quicker and less complicated.
For example:-Auto-tuning the Positioner to match the Valve characteristics.Setting the aggressiveness of the Positioner response
– This adjusts the speed of response.
If you had to do it manually, it would be like tuning a musical instrumentinstead of an electronic one.
26© 2007 Fieldbus Foundation
The Auto-tune Wizard allows easy set-up.Progress Screen
TimersResults Graph
Export to ExcelPID Comparison TableProgress Screen
Timers
27© 2007 Fieldbus Foundation
When we start to consider the Diagnostic abilities of Fieldbus equipment, we step into a bright, new world.
It gives us the ability to be ‘Electronic Doctors’ – assessing the health and well-being of our equipment.
The key is to do it in an easy to use and a comprehensible way.
Of course the full benefit comes from integration into a DCS.
28© 2007 Fieldbus Foundation
5 Pressure SensorsAir SupplyI/P OutP1 Relay OutP2 Relay OutAtmospheric Pressure
P Air Filter / Regulator
Servo (I/P)
Pneumatic Relay
Actuator
Valve
P1
P2
P3 P4
P5
CPU
C1
H1
T1
P4P3
P2C2
4-20 mASetpoint I/P Servo
The Heart of Diagnostics is in the Positioner, not the DCS.
29© 2007 Fieldbus Foundation
1 Temperature Sensor
2 Loop Current Sensor
1 Hall Travel Sensor
T
C
Air Filter / Regulator
Servo (I/P)
Pneumatic Relay
Actuator
P1
P2
P3 P4
P5
CPU
C1
H1
T1
P4P3
P2C2
H
4-20 mASetpoint I/P Servo
Having a high number of sensors allows the detection of more Valve issues.
Valve
30© 2007 Fieldbus Foundation
Types of diagnostics, which assist in maintaining and enhancing performance are:-
Continuous Diagnostic DataTime OpenTime CloseTime ‘Near’ ClosedCycle Count Travel Odometer
31© 2007 Fieldbus Foundation
More complicated and useful diagnostics are:-
Off-Line Signature DiagnosticsHigh Resolution Step TestHigh Resolution Extended TestPositioner Signature
On-Line Valve Diagnostics28 Alerts
– Including, Low Air Supply, Actuation Problem, Deviation, etc.
Careful and thoughtful use of this data provides us with an invaluable insight into the workings and condition of our Valves.
32© 2007 Fieldbus Foundation
On a more fundamental level, we can instantly see where the fault lies.Whether it is in regard to its Operation, its firmware or the electronics.Alarm Historian
Current and Historical for Every Alarm.Stays in Memory Even after Loss of Power.
33© 2007 Fieldbus Foundation
Accessing Diagnostic Data via a DCS – allows the sharing of data.
FF I/O
Valve alarmsActual positionIntegrated logic
TrendsValve timers
OperatorConsole
Asset ManagerCalibration,
Configuration,Literature
Etc.AssetManager
TB
Device alarmsHistorian timersValve odometerDeviation alarmCondition monitoring
FFPlug-In
DeviceViewer
Monitor StationControl Station
Valve SignatureUser FriendlyConfig. +Cal.TroubleshootCommissioning
Quick OverviewOf device/valveCondition.
database
FFStandAlone
High Speed Network
H1 Segment
34© 2007 Fieldbus Foundation
DeskPro
Data ArchivingPredictive Maintenance
OPC
Client
CONTINUOUSCycle Counter
Travel AccumulatorTime Closed
Time Near ClosedTime Open
OFFLINEPositioner Sign.Actuator Sign.
Step Sign.Overall FrictionSpring Range
Seat Load
ONLINEProcess TrendActual Travel
Output PressureInternal Set-pointDevice’s Health
FF COMMUNICATION
FF OPC
Fieldbus Valve Positioner
I/O SUBSYSTEM
L I F E B O O K Portable MaintenanceStation
Operator’sConsole
HandheldCalibrator
Maintenance Station
Valve D
iagnostics
Ethernet
Digital Positioner
35© 2007 Fieldbus Foundation
Being able to fully engage and interrogate your Fieldbus equipment from the control room is another great advantage.
It encourages the User to carefully examine the health, configuration and performance status of the Positioner/Valve while it is in action – backed-up by automated monitoring and self-checking features.
Without this ability, the only way to get data on Valve behaviour would be by going onto site and watching it for a few days.
36© 2007 Fieldbus Foundation
The data gives us access to the Process, Physical, Maintenance, Safety and Reliability information.
37© 2007 Fieldbus Foundation
The clever part is to convert the sophisticated performance and diagnostic data into a simple to interpret way.
In this case, a traffic light system is used – Red standing for a major problem, Orange for a predicted problem and Green for all OK.
38© 2007 Fieldbus Foundation
Creating Information From Data
Built-In historian in the Fieldbus Positioner 80
2015
92
8
80
65
35
1510
90
5
0102030405060708090
100
Valve A Valve B Valve C Valve D
hrs openhrs closedhrs n.closed
High % time nearly closed= Trim Erosion, Oversized Valve
Valve not being Exercised = Possible Stiction
Implementing Alarms in to the DCS
Historical Trace
39© 2007 Fieldbus Foundation
Case study
Industry Request
The Objectives The Tools
The Results
• Read Field Device Data Into DCS• Centralize Field Device Data• Manage Assets Effectively• Optimize Process Control
• Predict Valve Failure• Monitor Health of Valve• Analyze Applied Valves• Remotely Troubleshoot Valves
• A high quality, digital Positioner • Foundation Fieldbus protocol• Digital I/O’s or Multiplexors• AMS, PRM and Plug-In Concept
• Increase Process Yield• Reduce Maintenance Cycle• Online Overview Of Valve’s Health• Better Utilization of Man / Hours• Integrated Diagnostic In DCS
40© 2007 Fieldbus Foundation
Prognostics in action – Case study: BASF, Geismar, Lousiana
1) Total service Time =Time open + Time closed(59 + 6 hours = 65 Hours)
2) Cycles / Hour = Cycles / Service Time(5001/63 = 76.93 Cycles/Hour)
3) Life Estimate = [Life Estimate/Cycles / Hour] Minus[Current Accumulated Time]
[8,000,000/76.93] - [65] = 103925 Hours= 4330 Days= 11.86 Years
Terminal Life Estimation - Bellows Seal
1000
10000
100000
1000000
Valve Movement as a% of Free Travel
Valve Cycles( 000's )
Expected Cycle Life (000's)Masoneilan Design Criteria
Expected Cycle Life (000's) 1000 3500 10000 1000000
Masoneilan Design Criteria 3500
5.0% 4.0% 2.5% 0.30%
41© 2007 Fieldbus Foundation
Translation to Operational Expenditure savings:-
Industry Request
The Tools
The Results40% of industry costs relate to maintenance in some way
Request :-• Reduce maintenance costs on Power Plant• 40 Valves• Cost $110,000 every two years
Fieldbus technology was used to:-• Predict valve failure• Monitor health of the valves• Analyze valve behaviour• Remotely troubleshoot valves
Maintenance costs were reduced, as only 6 valves actually needed work:
Thus, costs cut from $110, 000
To $30,000 Made up of:-
Testing, field repair: $14,000Removal, Reintstallation and shop repair: $16,000
Power Plant: USA
42© 2007 Fieldbus Foundation