Home » Articles » Lipták

Voices: Lipták

RSS

Ultrasonic Flowmeters for Paper Pulp; Flowmeter Accuracy

A Reader Asks if Controlotron System 1010P Universal Portable Flowmeter Can Measure Pulp Flow With 1.5% Consistency. Also, Why Vendors' Literature, Often Give Accuracy Measurements as a Percentage but Without Stating of What

By Bela Liptak

Q: Can the Controlotron system 1010P Universal portable flowmeter measure pulp flow with 1.5% consistency. Is this flow device for clear water applications only?

Phillip Mngadi
Phillip.Mngadi@sappi.com

A: The short answer is yes, it can, but the subject deserves a more detailed answer: The Controlotron 1010P ultrasonic flowmeter is a portable, clamp-on sensor that is mounted on the outside of the pipe. Being clamp-on, it requires good acoustic coupling to the pipe to make sure that the coupling does not fail due to thermal expansion of the pipe or the drying out of the coupling material, nor will "ringing around the pipe" occur.

Because these flowmeters operate by averaging the velocity profile of the flowing fluid, the meter factor varies with the Reynolds number, so they can be used in the turbulent region (RE >> 10,000) or in the laminar region (RE < 4000), but not in the transition zone between them.

The Controlotron 1010P is better than the older clamp-on designs, because it uses "wide beam" technology, which injects the sonic wave into the pipe wall at its resonant frequency, exciting the pipe wall itself, so it becomes the transmitting device. It also can operate in either the transit time (more accurate) or the Doppler mode (less accurate), so if the pulp consistency is too high for the transmission mode, you can switch to Doppler.

The main limitation is accuracy, which is better with the dual-channel transit design than with the single-channel ones, but still is low. You did not give the flow range or velocity range you need to work with, nor did you indicate if you have 20 diameters of straight upstream pipe run, which is needed for the velocity profile to fully develop, so I am only guessing on accuracy.

I would say that you can go ahead using the 1010P if you can live with an accuracy of 5% AR in the transmission or 10% AR in the Doppler mode.

Béla Lipták
liptakbela@aol.com

A: Ultrasonic transit time flowmeters such as the Controlotron model mentioned are designed for homogenous liquids and some gases. The use of transit time ultrasonics in pulp flow with low density or consistency is possible, but the problem with ultrasonic flowmeters is that the speed of sound in a fluid is dependent on the density of the fluid. If the density (or pulp consistency) changes, so does the speed of sound, and this affects the measurement directly. Also, the higher the solids content, the more likely the sonic beam is to be attenuated to the point of uselessness.

For permanent installations I recommend using magnetic flowmeters for this application wherever possible.

Walt Boyes
wboyes@putman.net

A: The chances are it will work because the product is a combination of both time of flight (only works on clear homogeneous fluids, such as water) and Doppler (requires particulates or air bubbles in the process to operate). Some products claim to operate on clean fluids, provided there are eddies or flow perturbations in the process fluids that act like particulates, i.e., Reynolds number > 10,000.

Now your process, 1.5% consistency pulp stock (in water? in a CTMP mill?) is going to be a lot like water. A trial of the 1010P might be best in this case.

Peter Baker – CAP, CTech
Pbaker@ivyautomation.com

Q: When I look at vendors' literature, the accuracy is often given as a percentage without stating of what (of full scale? of actual reading? over what range?). The sales literature also often gives the accuracy of only the flow element, and does not include the error contributions of the loop components (transmitters, etc.) Do you know of a user-generated source of such information?

Harry J. Crowney
HCrowney@aol.com

A: All the flowmeter accuracy data in the four editions of my handbooks was based on user feedback and independent testing sources, not on manufacturers’ self-evaluation, and has always stated if the data is in %FS or %AR, and if it’s given only for the sensor or the whole loop. I know that the flow chapter is 253 pages, and the search takes some time, so here is a summary.

Béla Lipták
liptakbela@aol.com

---

More Voices

Ultrasonic Flowmeters for Paper Pulp; Flowmeter Accuracy
06/14/2013
A Reader Asks if Controlotron System 1010P Universal Portable Flowmeter Can Measure Pulp Flow With 1.5% Consistency. Also, Why Vendors' Literature, Often Give Accuracy Measurements as a Percentage but Without Stating of What

Relief Valve Blowdown Rings; D/P and Straight Runs
05/07/2013
Readers Ask: When It Comes to Safety Relief Valves, What Is Best? Using Two Blowdown Rings or Ones? and Can a Transmitter Be Installed Above Pipe Taps?

Automation Could Have Prevented Fukushima, 2
04/30/2013
Bela Liptak Discusses Automatic vs. Manual Operation of the Emergency Cooling Systems, and the Roles the Bad Designs of Control and Block Valves Played in this Nuclear Accident

Sealing an Oil Well; Orifice Sizing--OSO versus AGA
04/10/2013
Can Someone Explain BP's Sealing Process to Temporary Seal the Oil Well from the BP Oil Spill in the Mexican Gulf? And, What Is the Difference Between the Orifice Calculations Described by AGA 3 and ISO 5167?

Automation Could Have Saved Fukushima
03/15/2013
Liptak Says That If the Fukushima Level Detectors Had Operated Correctly, the Hydrogen Explosions Would Have Been Prevented

Loop Drawings for Smart Instruments
03/12/2013
Readers Look to Our Experts for Information on Smart Instruments

Automation Could Have Prevented Chernobyl
01/10/2013
Bela Liptak Tells How Automatic Safety Controls Could Have Prevented the Accident at Chernobyl

Cascade, Scan Time, PID Tuning
01/09/2013
When Should You "Slow Down" a PID Loop by Making the Loop Update Time Such That the Loop Executes Less Often?

Emergency Shutdown of LPG Tank Farms
12/10/2012
Is It Allowed from the Standard Point of View to Use the Existing Level Transmitters to Control the Inlet and Outlet Shutdown Valves?

Real-Time PIG Data Transmission?
11/12/2012
How Can We Improve the Safety of the Pipelining Industry? See What Our Experts Say

Why Nuclear Needs Process Automation
11/01/2012
The Key to the Safety of Nuclear Power Plants Is to Maintain the Availability of Coolants, Even if All Electric Power Supplies Fail

Crude Oil Pipeline Control
09/27/2012
Is It Possible to Maintain an Accurate and Stable Pressure Control Just Using Speed Control?

Economic Controls; Cooling Tower Optimization
09/10/2012
Readers' Ask Our Expert, Bela Lipatk, What His Opinion Is on Keen's Approach to Debuning Economics and to Give Some Advice on the Conceptual Design of Cooling Tower Optimization

Improving Oil and Gas Well Safety
08/29/2012
Liptak Walks Us Through Step-by-Step How Process Control Can Improve the Safety of Fracking, Off-Shore Drilling, Well Blow-Out Prevention, Drilling Ship Stability and Much More

"Herding" Control and LPG Problems
08/10/2012
A Reader Asks Us if "Herding Control" Is a Theoretical Concept, or a System that Our Very Own Bela Liptak Designed. Also, What Is the Suitability of Using a Differential Pressure Cell Pressure Transmitter.

D/P Cell Accuracy; Which Manifolds Are Best?
07/16/2012
A Reader Aks our Panel of Experts How He Can Tell If His D/P Transmitter is Accurately Calibrated. See What Our Experts Had to Say

Drilling Safely in the Arctic Ocean
07/03/2012
Liptak Shows Why Full Automation Could Improve the Safety of Offshore Drilling in and Transportation from the Arctic Ocean

Valve Failure Positions; Controlling Global Processes
06/12/2012
Readers Ask About PID Controller Action, Valve Failure Positions and Global Process Trends for Industrial Applications

Tuning Interacting Controllers
05/14/2012
Is the Famous Ziegler-Nichols (ZN) Open-Loop Tuning/Closed-Loop Tuning Parameter Calculation for Interacting or Non-Interacting PID?

Controls for Drilling Oil and Gas Wells
05/04/2012
The Drilling for Oil and Gas Will Be With Us for Some Time, the Only Contribution Our Profession Can Make Is to Improve the Safety of These Processes

Magmeter Maintenance, Feed-Forward Variations; Robots
04/11/2012
What Maintenance Is Required for a Magmeter? And What's the Difference Between "Positional Feed-Forward" and "Incremental Feed-Forward" in PID Control?

Using Feed-Forward PID for External Reset
03/08/2012
Is There a Way to Create an External Reset on a Standard PID Feedback Controller?

Scraping the Bottom of the Barrel-Part 3
03/02/2012
Liptak Discusses Pipelining Safety and How Automation Processes Can Prevent Pipelining Accidents

Deaerator Level Control
02/07/2012
Can a P Controller Be Replaced With a Linear Function Generator in Controlling the Level on a Deaerator?

Protecting Blast Furnace Pressure Transmitters from Plugging
01/10/2012
Installing a Pressure Transmitter for Dusty Service. Help Me Please!

Scraping of the Bottom of the Barrel -- Fracking
12/30/2011
Proponents Believe Fracking Gas Could Meet U.S. Energy Needs for a Century. Opponents Say the NG Supply Will Be Exhausted in Just a Few Decades

D/P Impulse Lines; Chinese Solar Tech
12/07/2011
How to Keep Impulse Lines Full of Water When the Pump Shuts Down, and Are the Controls, Converters or Collectors for Photovoltaic Designs Better Products?

Controls for Scraping of the Bottom of the Barrel - Part 1
11/07/2011
Discussing the Emerging New Industries That Are Aiming at Exploiting the "Unconventional" Fossil Fuel Deposits

Software for Renewable Energy Processes - 4
10/05/2011
Talking About Software Needs for Control and Optimization of Solar Energy Storage and Transportation Systems

How Automation Can Prevent Nuclear Accidents-Part 3
08/31/2011
Watch Out for Outdated and/or Unreliable Instruments. These Can Cause Major Disasters

More Reasons BWR Power Plants Are Unsafe
08/26/2011
Covering the Automation Errors That Exist in the Old American BWR Plants

Preventing Nuclear Accidents by Automation -- Part 2
07/05/2011
Bela Liptak Discusses the Design and Control Errors at Fukushima, Because They Still Exist in Many American Boiling-Water Reactors (BWR) and Must Be Corrected

The Fukushima Nuclear Accident - Part 1
04/15/2011
Béla Lipták Talks About the Safety Processes Used at the Fukushima Plant

Control Software for Renewable Energy - 6
03/04/2011
The Key Component of a Wireless and Fully Distributed Solar-Hydrogen System Is the Reversible Fuel Cell (RFC)

Software for Renewable Energy Processes-5
01/10/2011
Bela Liptak Describes the "Battery Swap"-Based Transportation and the "Energy Free" Housing He Sees for the Future

Software for Renewable Energy Processes - 4
10/28/2010
Solar Is the Fastest Growing Power-Generation Technology in the World

Control Software and Renewable Energy, Part 3
08/30/2010
Bela Liptak Discusses the Control of the Renewable Energy Processes That Use Energy Sources Such as the Sun, the Moon, the Rotation of Earth and Its Coriolis Effect and the Heat Below the Ground

Renewable Energy Processes, Part 2
07/02/2010
The Control System Must Be able to Detect the Loss of the Grid and Respond by Isolating Itself from the Grid or by Tripping Offline

Control Software and Renewable Energy, Part 1
05/03/2010
Columnist Bela Liptak Launches a Series of Articles Talking About Control Software in Need of Development for Renewable Energy Processes. Here is Article Number 1

Pumping Station Optimization, Part 3
03/04/2010
The Optimization of Pumping Stations and Liquid Distribution Systems Can Save 25 Percent or More Energy

Pumping Station Optimization - Part 2
01/08/2010
Bela Liptak Talks About the Phenomenon of Net Positive Suction Head (NPSH) and Multiple Pump Stations

Pumping Station Optimization - Part 1
11/03/2009
Liptak Describes the Pumping Process to Then Show How to Control and Optimize Pumping Stations

Process Control's Role in Nuclear Waste Handling
09/11/2009
Liptak Talks about the Role of Process Control in Nuclear Safety and How It Can Plays in Reducing the Risks Associated with the Transportation and Storage of Nuclear Wastes

Chernobyl Did Not Need To Occur
07/12/2009
Good Process Control Could Have Prevented this Historic Meltdown

What Caused the Three Mile Island Accident?
05/11/2009
Liptak Describes the Sequence of Events and the Primitive Controls That Led to the Three Mile Island Accident

The Future of Nuclear Energy
03/02/2009
If Global Carbon Emissions Were Cut by 15% by 2050 by the Increased Use of Nuclear Power, 1,070 Plants Would Need to Be Built at a Cost of $5 Trillion.

Nuclear Security, Part II—Fission Basics
01/09/2009
The Overall Topic of the Nuclear Power Plant Operation and the Use of Process Control to Protect Against Nuclear Accidents

Nuclear Plant Security and Cyber Terrorism
10/28/2008
How To Improve Nuclear Power Plant Security

Controlling the Post-Oil Energy Economy
08/20/2008
The World’s First Solar-Hydrogen Demonstration Power Plant

Fuel Cell of the Future
07/01/2008
Process Control Will Play a Key Role In the Transition From the Fossil/Nuclear Economy to the Solar-Hydrogen Economy of the Future

Green Energy Can Stop Recession
05/04/2008
Storing Solar Energy for the Night

The Third Industrial Revolution
03/07/2008
The Transition to a Solar/Hydrogen Economy Will Trigger an Economic Boom Unseen Since the Marshall Plan.

Distillation Control and Optimization – Part 7
01/03/2008
Plant-Wide Optimization Involves Coordinating the Control of Distillation, Furnaces, Compressors, etc. to Maximize the Profitability of the Entire Operation

On the Road to Renewable Transportation
11/06/2007
The OECD estimates that replacing 10% of the country’s motor fuels with bio-fuels would use one-third of all croplands.

The Global Energy Future – Part 5
08/31/2007
Covering 10 million American homes with solar roofs would trigger the biggest economic expansion of the decade.

Distillation, Part 5: Multiple Products
08/01/2007
In Part 5 of this series on distillation control and optimization, we find that adding a side-stream component to your process gives an additional degree of freedom, but makes it even more essential to not mismatch the variables.

The Energy Future—Process Control’s Role
07/12/2007
Find out about the “zero energy home of the future” and the hydrogen economy. What are the potentials of process control in wind, ocean wave, and geothermal energy systems.

The global energy future – Part 3
05/07/2007
Control's own Béla Lipták continues his series on the future of global energy, stating that in order to obtain maximum energy recovery, the various solar collectors described all need to track the sun.

Control of the solar-hydrogen plant
03/01/2007
Columnist Béla Lipták describes equipment and control requirements of the solar-hydrogen demo power plant and says we now are in critical need of them because the stakes are even higher.

The power of the Sun: Part 1
01/05/2007
In discussing global energy issues, CONTROL columnist Béla Lipták, PE, estimates that global warming damage will consume as much as 20% of the global GDP by 2020 even without energy wars.

How to select control valves, Part 2
09/12/2006
When it comes to selecting and sizing control valves and positioners, this article not only helps you pick the right one for the right job, but also includes a valuable valve selection chart you can download!

How to select control valves, Part 1
07/14/2006
When it comes to selecting and sizing control valves, the non-commercial chart in this article not only helps you pick the right one for the job, but also serves as a fantastic reference tool you can download!

Why do we have global warming?
05/18/2006
CONTROL columnist Béla Lipták, PE, finishes his Lessons Learned series on global warming, and what the process control confraternity can do about understanding and perhaps controlling it.

Can process control help stabilize global warming?
03/14/2006
CONTROL columnist Béla Lipták, PE, continues his Lessons Learned series on Global Warming, and what the proceess control confraternity can do about predicting the timing and sizing of future events.

A process only mankind can control
01/09/2006
Global warming, devastating hurricanes and rising ocean currents are all signs of a presently-out-of-control global heat balance that may result in colder winters and our summers permanently disappearing.

Engineers can control the economy: Part II
11/14/2005
In this second installment, CONTROL Columnist Béla Lipták, PE, illustrates an assumed ANN model of the U.S. economy to show what can happen when advanced process control meets economics.

Can an automation engineer control the economy?
09/10/2005
In this month's installment of his Lessons Learned column for CONTROL magazine, columnist Béla Lipták, PE, shows what can happen when advanced process control meets economics.

Getting Loopy with Control Loops
07/20/2005
This month's edition of Ask The Experts focuses in on manual control loops and offers guidance on which PID control mode should be used when, and what the range of tuning settings should be.

The next generation of smarter valves – Part 2
07/10/2005
Much improvement and change is expected in the design of smart and self-diagnosing control valves, with potential advantages outweighing the required investment of time and money.

The next generation of smarter valves
05/10/2005
In the next decade, much improvement and change is expected in the design of smart and self-diagnosing control valves, with potential advantages outweighing the required investment of time and money.

The fuel cell: A new process to control
09/20/2002
The fuel cell is like a battery, except that it never needs recharging because the heat and electricity produced by it are made from the inexhaustible and clean sources of water and air.