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Residing on Residence Time

April 20, 2020
The time spent residing on this column is time well spent if you want to become famous for improving process performance with the side benefit of becoming best buds with the process...
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Variability Appearance and Disappearance

March 7, 2020
Particularly confusing is variability that seems to come out of nowhere and then disappear. There are not presently good tools to track down the sources because it turns out most...
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Lowdown on Turndown

Feb. 3, 2020
There are a lot of misconceptions on what is the turndown capability of measurements and final control elements (e.g., control valves and variable frequency drives). Here is a...
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Biggest Valve Sizing Mistake

Dec. 4, 2019
There is a common mistake made in the sizing of most control valves. The intentions that lead to this mistake may be good but the results are insidiously bad. While you would ...
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Missed Opportunities in Process Control - Part 6

July 31, 2019
Here is the Sixth part of a point blank decisive comprehensive list of what we really need to know in a detailed attempt to reduce the disparity between theory and practice. Please...
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Missed Opportunities in Process Control - Part 5

June 24, 2019
Here is the Fifth part of a point blank decisive comprehensive list of what we really need to know in a detailed attempt to reduce the disparity between theory and practice. Please...
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Missed Opportunities in Process Control - Part 4

May 1, 2019
Here is the Fourth part of a point blank decisive comprehensive list of what we really need to know in a detailed attempt to reduce the disparity between theory and practice. ...
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Missed Opportunities in Process Control - Part 3

March 26, 2019
Here is the third part of a point blank decisive comprehensive list of what we really need to know in a detailed attempt to reduce the disparity between theory and practice. Please...
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Missed Opportunities in Process Control - Part 2

Feb. 24, 2019
Here is the second part of a point blank decisive comprehensive list of what we really need to know in a detailed attempt to reduce the disparity between theory and practice. ...
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Missed Opportunities in Process Control - Part 1

Jan. 18, 2019
I had an awakening as to the much greater than realized disconnect between what is said in the literature and courses and what we need to know as practitioners as I was giving...
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Many Objectives, Many Worlds of Process Control

Oct. 22, 2018
In many publications on process control, the common metric you see is integrated absolute error for a step disturbance on the process output. In many tests for tuning, setpoint...
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When is Reducing Variability Wrong?

Sept. 2, 2018
Having the blind wholesale goal of reducing variability can lead to doing the wrong thing that can reduce plant safety and performance. Here we look at some common mistakes made...
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How to Prevent Acceleration, Jumping and Oscillation of Unstable Processes

July 14, 2018
Inverse response, negative resistance, positive feedback and discontinuities can cause processes to jump, accelerate and oscillate confusing the control system and the operator...
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Maximizing Synergy between Engineering and Operations

June 12, 2018
The operator is by far the most important person in the control room having the most intimate knowledge and “hands on” experience with the process. Engineers who are most successful...
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Invitation to Join an Expanded ISA Mentor Program

Nov. 16, 2015
The ISA Mentor Program, started by Greg McMillan and Hunter Vegas in 2011, is extending its invitation to prospective protégés/protégées and resources to include any engineer ...