Presentation on theme: "Large-Scale Controller Performance, Assessment, Diagnosis and Improvement Mike Paulonis Eastman Chemical Company Presentation to: East TN AIChE Feb 2005."— Presentation transcript:
Large-Scale Controller Performance, Assessment, Diagnosis and Improvement Mike Paulonis Eastman Chemical Company Presentation to: East TN AIChE Feb 2005
MAP Collaboration Co-creator of controller performance assessment at Eastman John Cox
MAP Agenda Productivity – The Driver Circumstances Leading to Development System Overview Performance Assessment Details / Screenshots Application Results Summary
MAP Sources of productivity Process Automation Information Technology Process Improvement More volume Fewer people
MAP A closer look at process automation Generating productivity Enable stable plant operation at higher rates Enable a higher percentage of first-class product Enable plants to run safely with fewer operators Affected by productivity changes YearAdvCT employees
MAP Increase in process control work on existing plants revealed many control loops with poor performance Partial cause was a decrease in number and availability of personnel to monitor/troubleshoot control loops Control loop/valve maintenance mode was “run until failure” The need for a system to efficiently detect and diagnose poor control loops became apparent Increase control engineer productivity Enable plant engineers to do more on their own Focus on 1999
MAP More from 1999… Honeywell introduced "Loop Scout" to general customers The good: assess control loop performance from historical operating data The bad: Cost: $350 per loop per analysis! Only accepted data from Honeywell control systems Have to send the controller data to Honeywell for analysis
MAP We can do better (we think) Our vision for controller performance assessment Interfaces to all Eastman control and data systems Analyze thousands of loops automatically and periodically Rank loop performance to quickly find opportunities Users can pull up current or historical performance of any loop (interactive discovery) Users can get reports on controller performance specific to their plant (exception processing) Reports have summaries understandable by anyone and details for in-depth analysis by control engineers Capture controller tuning changes which often link with performance issues
MAP Read a lot of academic papers Implemented assessment algorithms in Matlab Tested/improved using real plant data Automated the capture of bulk data from control systems Automated the analysis of bulk data Improved some more – hand tuned classification algorithm from about 100 example loops Built a database to house all the analysis results and service user queries Built a web application using Cold Fusion to bring it all together and make it accessible to everyone Build it!
MAP System architecture Distributed data collection Distributed computing resources Server-side web programming Linked in to wide-area network
MAP Eastman’s large-scale system Ten sites Forty-nine process areas Interfaces to a variety of control systems Daily tuning history on 14,000 loops Weekly performance history on 8,500 loops
MAP Use mode 1 - Tell me about a loop
MAP Example help
MAP Use mode 2 - Find problem loops
MAP Find problem loops Worst Best
MAP Push content for busy people subscription reports Monthly performance detail Top 20 losers and gainers Rankings worst to best Monthly performance summary Performance by loop type Performance by loop type over the last year Performance benchmark Eastman-wide Daily tuning changes Notification - tuning changes often mean other problems Monthly tuning detail
MAP Neat pictures, but does it really work? Primary question around valve problems Controller performance assessment showed many problems Most seemed to be valve-related, not tuning Valves need maintenance - culture change Valve repair/replacement costs $$$ Don't want a lot of false positives on valve diagnoses Open it 100%, OK, now close it!
MAP Second pass - entire classes Reactor Dowtherm control valves all have motion problems (some up to 15% deadband) Why? Long stem High-temp packing Dirty conditions No positioner Solution? Critical service Replace all A significant milestone!
MAP The trend looks good New Dowtherm Valves
MAP Improvement in every category December 2000 September 2002
MAP Beating the “competition” December th of 24 areas 50th percentile September th of 36 areas 83rd percentile
MAP The payoff (2001 vs. 2000) Reduction in off-class production Reactor level klbs (80% reduction) Reactor temperature - 52 klbs (80% reduction) Vacuum klbs (35% reduction) Product specs - 96 klbs (35% reduction) 98.5% class 1 production - best ever Reduction in startup and transition off-class 8.1 klb/startup (22%), 19.3 klb/transition (70%) Over 1 million lb/year - maybe 15-25% from control Line run-life H-line best ever 222 days (9/10/01 - 4/19/02) Customer complaints down 55%
MAP Long-term monitoring ImproveMaintain the gainImprove
MAP The bottom line A revolution in knowledge for users of all levels Find problems that are not obvious Troubleshooting time reduced by 2/3 or more Monitor and benchmark performance over time for continual improvement Enables effective approach to controller maintenance Encourages communication between control engineers, staff engineers, area managers, and maintenance forces Generates significant economic gains
MAP Another example Another polymers area embarked on a control improvement project in 2003 using performance assessment to identify opportunities and track results Focused on problem loops critical to operation Added smart positioners to key valves Replaced some undersized valves Fixed some slave controller wind-up problems Implemented measurement filters where appropriate Did some control strategy redesign Much more…
MAP Great results!
MAP In search of excellence
MAP Other areas can do this too Engineer signs up for monthly reports Engineer receives and reviews monthly reports What is bad, what is good? Get management buy-in Control loops need maintenance Controller performance is important Engineer prioritizes loops Criticality, return on investment Enlist help of CSM, E&I shops, Reliability Technology and AdvCT as needed Engineer arranges funding and schedule for fix Engineer follows up to identify tangible benefits
MAP Summary Controller performance can be determined from historical operating data Eastman's home-grown system does this weekly for thousands of controllers world-wide Users can get performance information from a web site and/or have it ed to them With the system, work can quickly be focused on the best opportunities Improved controller performance leads to improved process performance and greater profitability We can now do much more with less