What Are Variable Area Flow Meters?
Variable Area Flow Meters: An Overview
Developed by German inventor Karl Kueppers in 1908, Rotameters measure the volumetric flow rate of liquids and gases.
Important elements of a variable area flow meter include the tube and the float. Their operation is simple. The tube is fixed vertically and the fluid is fed from the bottom. It travels upward and exits from the top. The float remains at the bottom when no liquid is present and rises upward when fluid enters the tube.
The float inside the tube moves in proportion to the rate of fluid flow and the area between the tube wall and the float. When the float moves upward, the area increases while the differential pressure decreases. A stable position is reached when the upward force exerted by the fluid is equal to the weight of the float. A scale mounted on the tube records the flow rate of the liquid. Usually, the flow can be adjusted manually using a built-in valve.
Types of Variable Area Flow Meters
Variable area flow meters can be categorized by the type of tube they use, which relates to their ability to withstands various pressures, temperatures, process media, and cost. Process connection size and wetted part materials vary as a function the rotameter type and construction.
Plastic Tube Variable Area Flow Meter - For many non-corrosive, low-pressure air, water and gas flow applications. Made of machined acrylic or molded polycarbonate.
Plastic Tube Variable Area Flow Meter Applications:
- Water treatment systems
- Gas analyzers
- Air sampling equipment
- Desalinization equipment
- Medical equipment
- Photo processing equipment
- OEM machines
Glass Tube Variable Area Flow Meter - The basic glass variable area flow meter consists of borosilicate glass tube while the float is made of either glass, plastic, or stainless steel. The most common combination is a glass tube and metal float. This is suitable for a measure the flow rate of liquid of low to medium temperatures and pressures.
Glass Tube Variable Area Flow Meter Applications:
- Analytical instrumentation
- Industrial processes
- Chemical production
- Pharmaceutical production
- Oil & gas extraction
- Refining processes
- Fuel cell research
- Water treatment systems
Metal Tube Variable Area Flow Meter - Metal tube variable area flow meters are another type thatis suitable for temperatures and pressures beyond the physical and mechanical limits of glass tube versions. They are generally manufactured of stainless steel, aluminum, or brass. The piston position is determined by the mechanical and magnetic followers that can be read from the outside of the tube. They are suitable in situations where applications conditions would damage the glass metering tubes, such as steam applications.
Metal Tube Variable Area Flow Meter Applications:
- Purge liquid or gas metering
- Liquid, gas, or oil flow measurement
- Chemical injection
- Rotating equipment flow measurement
- High-pressure flow meters for offshore oil platforms
For more information about variable area flow meters, contact Thomson Equipment by calling 800-528-8997 or visit their web site at https://teco-inc.com. TECO is a National ABB Rotameter Stocking Distributor and has many of the models you need on their shelves now.
New Batch of Severe Service Magmeters for Fracing Service from TECO
For more information about severe service magnetic flowmeters, contact Thompson Equipment Company by calling 800-528-8997 or visit https://teco-inc.com.
A Special Connection Between D-Day and TECO
 |
| TECO Headquarters |
Todd Thompson, President of Thompson Equipment, has a very special story to tell on D-Day.
 |
| Higgins Boat full of soldiers. |
"My great grandfather Horace Thompson Sr., the father of TECO’s founder, Horace Thompson, Jr., was the head of the US Army Corps of Engineers in New Orleans. He had a need for a vessel that could work on the river side of the Mississippi River levees. His friend Andrew Higgins developed the solution, which was ultimately mass produced in New Orleans and used in WWII as the Higgins Landing Craft. "
 |
| Higgins Landing Craft statue given to Horace Thompson by Andrew Higgins. |
Mr. Thompson goes on to say, "Obviously this is a meaningful day for all Americans, but in New Orleans and at TECO, we feel particularly proud of the accomplishments of our forefathers every 6th of June."
A warm "Happy Landings" to all of you from TECO on this very special day.
A warm "Happy Landings" to all of you from TECO on this very special day.
Volumetric Flow, Pressure, Temperature, and Totalizer All-in-One for Compressed Air Systems
The ifm SD ”All-in-one sensor“ compressed air flowmeter integrates a temperature sensor and a pressure sensor, allowing the user to read four process values at once (volumetric flow, pressure, temperature, totalizer = total quantity meter).
The SD’s precise flow monitoring allows for leakage detection and energy cost savings. Thanks to the integrated pressure measurement, both the pressure drop on the polluted filter systems and the compressed air system’s general operating pressure can be optimally monitored.
For more information, contact Thompson Equipment Company. Phone them at 800-528-8997 or visit their website at https://teco-inc.com.
Magnetic Flow Meters: Basic Principles
The operation of magnetic flow meters is different than other measurement devices. The post will highlight the basic principles of the device and also shed light on pros, cons, and industrial application.
Basic Principle of Magnetic Flow Meters
Magnetic flow meters are also known as electromagnetic flow meters or mag meters. The principle of magnetic flow meter is based on Faraday’s Law of Electromagnetic induction. The law states that a voltage produced across a conductor as it moves through the magnetic field at right angles is directly proportional to the velocity of that conductor.The device creates a magnetic field to channel the flow of fluid through a pipe. As the fluid passes through the magnetic field, a voltage signal is created. The faster the fluid flows through the pipe, the higher the voltage produced by the device.
The voltage is picked up by electrode sensors that are located inside the tube. The signals are then conveyed to an electronic transmitter that processes the signal to determine the velocity of the fluid flow.
Benefits of Magnetic Flow Meters
Magnetic flow meters can be installed in shorter meter runs since they don’t require much upstream and downstream runs. The volumetric flow meters have little or no moving parts and require less maintenance making them a cost-effective option for many industrial applications.Another benefit of the industrial application of magnetic flow meters is that they have a low-pressure drop. Only a slight pressure drop results depending on the length of the tube. This results in more accurate measurement of the liquid flow velocity.
Magnetic flow devices are based on the principle of a linear relationship between the measuring signal and flow rate. In contrast, most other pressure devices work on the principle of a square law relationship. This results in a higher rangeability and accuracy of the magnetic meters.
An important thing that you should keep in mind is that the magnetic flow meters are susceptible to air bubbles. The device cannot differentiate between the process fluid and entrained air. So, the air bubbles will result in an incorrect reading. Air bubbles will cause the meter to give a high reading.
Another thing to remember is that the pipe should be filled completely with water. An incorrect reading will result if the pipe is not full. A solution for this is to install the sensor about 45 to 130 degree angle.
Application of Magnetic Flow Meters
Magnetic flow meters can measure velocities of all conductive liquids including water, slurries, and acids. More specifically, the device can measure velocities of liquids with electrical conductivity greater than 5μS/cm.Since the flow meter is obstruction-less, the device is generally applied to measure the velocity of dirty, sanitary, abrasive, and corrosive liquids.
However, the device cannot be used for measuring velocities of liquids with low electrical conductivity such as boiler feed water, deionized water, and hydrocarbons. In addition, the device can also not measure the velocity of gasses.
Types of Magnetic Flow Meter
You can find three common types of a magnetic flow meter in the market. The devices are suitable for different industrial application.Insertion Magnetic Flow Meter
The insertion magnetic flow meter is best for measuring liquid flow in large pipes. The device is simple to install and deliver accurate measurement across a range of pipe sizes.Inline Magnetic Flow Meter
Inline magnetic flow meter is ideal for situations where high accuracy is necessary. The device is generally used for measuring the liquid flow of slurries, wastewater, food, and pulp.Unlike insertion magnetic flow meters, inline flow meters don’t require a straight pipe. Moreover, they are best in assessing liquid with higher flow rates.
Low-flow Magnetic Meters
Low-flow magnetic meters are great for assessing liquid with low flow rates. They are designed in a way to prevent fouling. Similar to insertion magnetic flow meters, the low-flow meters do not require straight pipe. In addition, the device can be used in situations where little space is available between the elbow and the meter.Magnetic flow meters are reliable in measuring velocities of conductive fluid. The devices have a wide range of industrial application, particularly in commodity transfer. They provide accurate reading and undergo less wear and tear. They are a reliable and cost-effective option for measuring the fluid flow of all conductive fluids.
The device can be used to accurately measure the fluid flow of untreated sewage water, processed water, and aggressive chemicals in water treatment, mining operations, and pulp and paper industries.
For more information on magnetic flow meters, contact Thompson Equipment Company (TECO) by calling 800-528-8997 or by visiting https://teco-inc.com.
Subscribe to:
Posts (Atom)