The Top 10 Fluid Flow Measurement Application Questions

Variable area flow meter (ABB)

Measurement of flow is essential for operation, control, and record keeping for chemical manufacturing, water treatment, oil and gas production, refining, and many other processes. The accurate and reliable measurement of flow is essential to ensuring the proper and efficient operation of any flow control loop. Various technologies such as Coriolis, differential pressure, vortex, magnetic, ultrasonic, turbine and positive displacement meters can be used to measure flow. All of these technologies have advantages and disadvantages. Understanding the differences can be the difference in a successful flow meter implementation or a failure.  Before the proper technology can be selected, there are 10 basic application question that must be answered. They are:

Severe service flow meter
(TECO)

1. Is the measured process media a liquid or a gas?
2. Is the flow measurement occurring in a pipe or in an open channel?
3. What is the the flow rate?
4. How much does the flow vary?
5. If liquid,  is it clean or does it contain suspended solids or air bubbles?
6. What accuracy is required?
7. How much head loss by the flowmeter is permissible? 
8. Is the flow corrosive or erosive?
9. What types of flowmeter technologies can be accommodated in the location?
10. What types of post installation service is available in area?

Positive Displacement Meter (Blancett)

Selecting and configuring a flow measurement device properly, and assuring that installation is done correctly, are necessary tasks to achieving optimal flow meter performance. Reach out to a flow meter specialist with your flow application. By combining your process knowledge with their product application expertise, an effective and long lasting solution will result.

For more information about any flow measurement application, contact Thompson Equipment. The can be reached by calling 800-528-8997 or by visiting https://teco-inc.com.

Get Your Process Flow Meters Remanufactured Instead of Buying New

Cutaway before and after of remanufactured flow meter.

Head scratcher. Why buy brand new flow meters when there are companies in the USA that have the trained technicians and facilities ready to remanufacture your old flow meters to a condition better than new?

Remanufactured flow meters meet or exceed all OEM specifications and performance standards. Here's how it works. Experienced technicians break down your flow meter to it's core components - flowtube, electronics, enclosure, flanges, and electrical. All parts are evaluated for wear and tear. All components are cleaned, primed, and painted. New electronics, flow sensors, liners, and electrical connections are installed. Once assembly is complete, the "remanufactured" flow meter goes through an exhaustive quality control process and is calibrated to NIST traceable standards using an advanced, state-of-the-art calibration facility.

Remanufactured flow meter.

All this is done very efficiently, quickly and cost-effectively.  You just ship your old instrument in to the attention of the "Repair Department". No RMA is required. The company evaluates your old flow meter and then generates a quote with delivery time for the remanufactured meter (normally within 48 hours).

Here is a summary of the benefits for choosing remanufacturing:

• All brands of flow meters are candidates.
• NIST traceable certificate is provided.
• Obsolete flow meters are no problem.
• No evaluation fees charged.
• Accessories are included.
• New warranty is given.
• Failure analysis is provided.
• Flow meters can be repurposed for severe service (enhanced during remanufacturing).
• Remanufacturing is GREEN and environmentally friendly.

For more information, visit this flow meter remanufacturing link or call 800-528-8997.

What Are Orifice Plates?

Fig. 1 - Orifice Plates

The orifice plate is the simplest of the flowpath restrictions used in flow detection, as well as the most economical. Orifice plates are flat plates 1/16 to 1/4 inch thick. They are normally mounted between a pair of flanges and are installed in a straight run of smooth pipe to avoid disturbance of flow patterns from fittings and valves.

Three kinds of orifice plates are used: concentric, eccentric, and segmental (as shown in Figure 1).

The concentric orifice plate is the most common of the three types. As shown, the orifice is equidistant (concentric) to the inside diameter of the pipe. Flow through a sharp-edged orifice plate is characterized by a change in velocity. As the fluid passes through the orifice, the fluid converges, and the velocity of the fluid increases to a maximum value. At this point, the pressure is at a minimum value. As the fluid diverges to fill the entire pipe area, the velocity decreases back to the original value. The pressure increases to about 60% to 80% of the original input value. The pressure loss is irrecoverable; therefore, the output pressure will always be less than the input pressure. The pressures on both sides of the orifice are measured, resulting in a differential pressure which is proportional to the flow rate.

Segmental and eccentric orifice plates are functionally identical to the concentric orifice. The circular section of the segmental orifice is concentric with the pipe. The segmental portion of the orifice eliminates damming of foreign materials on the upstream side of the orifice when mounted in a horizontal pipe. Depending on the type of fluid, the segmental section is placed on either the top or bottom of the horizontal pipe to increase the accuracy of the measurement.

Eccentric orifice plates shift the edge of the orifice to the inside of the pipe wall. This design also prevents upstream damming and is used in the same way as the segmental orifice plate.
Orifice plates have two distinct disadvantages; they cause a high permanent pressure drop (outlet pressure will be 60% to 80% of inlet pressure), and they are subject to erosion, which will eventually cause inaccuracies in the measured differential pressure.

Contact TECO with any process flow question or requirement. You can find them by visiting https://teco-inc.com or by calling (504) 833-6381.

Industrial Control Valve Design and Operation

The design and operation of industrial control valves  is very important to understand if you work as a process engineer, a plant maintenance person, or if you design process control loops.

Control valves are used extensively in power plants, pulp and paper mills, chemical manufacturing, petro-chemical processing, HVAC and steam distribution systems.

There are many types, manufacturers, body styles, and specialized features, but the they all share some basics operating principles. The video below explains components, operation, and fundamentals.

TECO designs automated control valve systems for all major industries including chemical, pulp and paper, petro-chemical, power generation, and water treatment.  TECO’s experience and engineering background make them a uniquely qualified partner for your next automated valve requirement.

https://www.teco-inc.com
800-528-8997

Introduction to Transmitters used in Process Control

Flow transmitter (ModMag)

Transmitters are process control field devices. They receive input from a connected process sensor, then convert the sensor signal to an output signal using a transmission protocol. The output signal is passed to a monitoring, control, or decision device for use in documenting, regulating, or monitoring a process or operation.

In general, transmitters accomplish three steps, including converting the initial signal twice. The first step is the initial conversion which alters the input signal to make it linear. After an amplification of the converted signal, the second conversion changes the signal into either a standard electrical or pneumatic output signal that can be utilized by receiving instruments and devices. The third and final step is the actual output of the electrical or pneumatic signal to utilization equipment - controllers, PLC, recorder, etc.

Transmitters are available for almost every measured parameter in process control, and are often referred to according to the process condition which they measure. Some examples.

• Pressure transmitters
• Temperature transmitters
• Flow transmitters
• Level transmitters
• Vibration transmitters
• Current, voltage & power transmitters
• PH, conductivity, dissolved gas transmitters, etc. 
• Consistency

Consistency Transmitter(TECO)

Output signals from transmitters, when electrical, often are either voltage (1-5 or 2-10 volts DC) or current (4-20 mA). Power requirements can vary among products, but are often 110/220 VAC or 24 VDC.  Low power consumption by electrical transmitters can permit some units to be "loop powered", operating from the voltage applied to the output current loop. These devices are also called "two-wire transmitters" because only two conductors are connected to the unit. Unlike the two wire system which only needs two wires to power the transmitter and carry the analog signal output, the four-wire system requires four separate conductors, with one pair serving as the power supply to the unit and a separate pair providing the output signal path. Pneumatic transmitters, while still in use, are continuously being supplanted by electrical units that provide adequate levels of safety and functionality in environments previously only served by pneumatic units.

Pressure
Transmitter
(ifm)

Many transmitters are provided with higher order functions in addition to merely converting an input signal to an output signal. On board displays, keypads, Bluetooth connectivity, and a host of industry standard communication protocols can also be had as an integral part of many process transmitters. Other functions that provide alarm or safety action are more frequently part of the transmitter package, as well.

Wireless transmitters are also available, with some operating from battery power and negating the need for any wired connection at all. Process transmitters have evolved from simple signal conversion devices to higher functioning, efficient, easy to apply and maintain instruments utilized for providing input to process control systems.

To lean more about instrumentation and control, visit http://www.teco-inc.com or call Thompson Equipment at 800-528-8997.

The Operating Principles of a Magnetic Flowmeter

Below is a video, courtesy of Badger Meter, illustrating the operating principles of magnetic flowmeters (also known as magmeters).

A magnetic field is applied to the flow tube, resulting in an EMF proportional to the flow velocity passing perpendicular to the magnetic flux lines. The physical principle at work is Faraday's law of electromagnetic induction.

Magnetic flow meter requires a conductive fluid, and electrically insulated internal pipe surfaces to operate.

Advantages:

• Low maintenance cost
• No moving parts
• Good for slurry
• Good for corrosive fluids
• Very linear
• Minimal flow restriction

Disadvantages:

• Requires electrically conductive fluids

For more information on magmeters, visit TECO at http://www.teco-inc.com of call 800-528-8997.

TECO HK Series Microwave Consistency Transmitter Technical Review

TECO HK Series
Microwave Consistency Transmitters

The TECO HK Series microwave consistency transmitters provide a versatile, safe and easy-to-calibrate means for measuring the consistency of paper stock. The HK Series can successfully measure broke, recycle or other difficult fiber types, independent of fiber length, freeness or wood species.

Typically less than half of the cost of other microwave transmitters, the HK series microwave transmitters will measure the percentage of total solids of additives in water and percentage of moisture in wood chips with the same transmitter. Applications include measurement and control of machine, recycle & broke stock, measurement and control of % totals solids of starch additives, measurement and control of % solids (limestone, kaolin clay) in coatings.

• Low cost – typically less than half the cost of other microwave transmitters
• Easy to install
• One point calibration
• Adjustable antenna units to maximize sensitivity to process conditions
• Internally compensated for temperature
• No routine maintenance required. Install & forget!
• Current and Digital Outputs
• Contact closure
• Versatile – Same transmitter can be used in Pipes, tanks, chests, belts & chutes.

Applications:

• Paper and Board Mills:
  • Machine Stock Consistency Measurement and Control
  • Broke Consistency Measurement and Control
• Paper Mills
  • Bleaching State Feed Consistency
  • Consistency Measurement & Control in Fiber Lines with changing Wood Species
  • Production Measurment at Integrated Mills
• Mechanical Pulp Plants
  • Refiner Consistency
  • All Fiber Line Consistency Measurments and Control
• De-inking Pulp Plants
• Consistency and Control of Deinking Pulp
• Production Measurement of Deinking Pulp

TECO HK Series Microwave Consistency Transmitter Technical Review from Thompson Equipment Company