Friday, June 28, 2019

A Mass Flow Meter that Works with YOUR Control System: The Brooks SLA5800 Series

SLA5800
Improve your processes with the EtherNet/IP-enabled SLA5800 Series MFC. By adding non-proprietary communications and lightning fast data transfer to the SLA5800’s high accuracy, repeatability and rich data, Brooks Instrument just made the most stable mass flow controller even better. Best of all, it's compatible with all major control system manufacturers, including Allen-Bradley (Rockwell Automation), Emerson DeltaV and Siemens.

The SLA5800 Series mass flow meters and mass flow controllers have gained broad acceptance as the standard for accuracy, stability and reliability. These products have a wide flow measurement range and are suitable for a broad range of temperature and pressure conditions making them well suited for chemical and petrochemical research, laboratory, analytical, fuel cell and life science applications, among others.

Highlights of the SLA5800 Series mass flow products include: industry leading long term stability, accuracy backed by superior metrology systems and methods using primary calibration systems directly traceable to international standards, and a broad range of analog and digital I/O options to suite virtually any application. An independent diagnostic/service port permits users to troubleshoot or change flow conditions without removing the mass flow controller from service.



Flow-Tech, Inc.
410-666-3200 MD or 804-752-3450 VA
https://flowtechonline.com

Tuesday, June 18, 2019

Variable Area Flow Meters

Variable area flow meters

Variable area flow meters, also referred to as Rotameters, have diverse industrial processing applications that range from simple to sophisticated. The devices are easy to install, require no electrical connection, and provide direct flow rate reading. They provide fail-safe flow rate readings in a wide array of industrial applications.

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 withstand various pressures, temperatures, process media, and cost. Process connection size and wetted part materials vary as a function of the rotameter type and construction. 

Plastic variable area flow meter
Plastic Tube
Rotameter
(Brooks)

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.

Applications:
  • Water treatment systems
  • Gas analyzers
  • Air sampling equipment 
  • Desalinization equipment
  • Medical equipment
  • Photo processing equipment
  • OEM machines
Glass variable area flow meter
Glass Tube
Rotameter
(Brooks)

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. 

Applications:
  • Analytical instrumentation
  • Industrial processes
  • Chemical production
  • Pharmaceutical production
  • Oil & gas extraction
  • Refining processes
  • Fuel cell research
  • Water treatment systems
Metal variable area flow meter
Metal Tube
Rotameter
(Brooks)

Metal Tube Variable Area Flow Meter

Metal tube variable area flow meters are another type that is 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.

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, contact Flow-Tech, Inc. by calling 410-666-3200 in Maryland or 804-752-3450 in Virginia. Or, stop by the website at https://flowtechonline.com.

Friday, May 31, 2019

Electromagnetic Flowmeters and Dual Frequency Excitation

Magnetic flowmeter
(Yokogawa)
The electromagnetic flowmeter, commonly known as the "magmeter", gets its name from the magnetic field generated within the float tube that produces a signal proportional to flow. This principle employs Faraday's Law of Electromagnetic Induction. Magnetic flowmeters are built so the direction of the magnetic field is perpendicular to the flow and the line between the electrodes is also perpendicular to the flow. As a conductive liquid flows through the flowtube, an electro-motive force is generated. The electrodes detect the electro-motive force. The electro-motive force is proportional to the flow velocity, flux density, and the meter inner diameter. The flux density of the magnetic field and the meters inner diameter are constant values, therefore the magnetic flow meter can calculate the flow velocity and volumetric flow from the electro-motive force.

The basic components of the magnetic flow meter body are:
  • A lined flowtube (typically Teflon)
  • Excitation coils
  • Two electrodes mounted opposite of each other within the flowtube.
Current is applied to the coils in the magmeter to generate a magnetic field within the flow tube. As a conductive fluid flows through the meter, an electro-motiveforce is generated. This force is detected by the electrodes and the resulting value is converted to flowrate.

When magnetic flow meters were originally designed over 50 years ago, they utilized AC type excitation. AC powered magnetic flow meters use line frequency to generate the magnetic field. The frequency of AC excitation is typically 50 to 60 Hertz. This type of excitation has a very fast response time, making it suitable for slurry applications. The weakness of AC type excitation is that it has an unstable zero, and the accuracy is a percent of span, as opposed to a more accurate percent of reading. Because this type of excitation uses line frequency, the power consumption is also very high, making this an expensive meter to operate.

AC and DC excitation
Dual AC and DC excitation
In an effort to improve accuracy and reduce energy cost, pulsed DC type excitation was introduced several years later. The average excitation frequency is between three to eight Hertz, but can go as high as thirty Hertz. The major benefits of pulsed DC excitation over AC excitation is the improved accuracy and zero stability. The accuracy of a DC type meter is a percent of reading. This gives you a more accurate measurement throughout the entire measuring range. Unfortunately, because of the low frequency, the response time is very slow, making it a poor choice for noisy applications.

To overcome the disadvantages of the standard AC and DC excitation methods, and keep the advantage of a high signal-to-noise ratio, Yokogawa's patented dual frequency excitation is the ideal combination. Dual frequency excitation combines the positive benefits of both AC and DC excitation, using both a high 75 Hertz frequency, and a low frequency excitation of approximately six Hertz to drive the coils. Dual frequency excitation is an innovative method that superimposes high frequencies on low frequencies, and utilizes the advantages of each, while eliminating the previously discussed disadvantages. The combination of these methods results in the flow noise immunity and fast response of the high frequency excitation method, and the high zero stability of the low frequency excitation method simultaneously.

For more information on Fike products and capabilities, contact Flow-Tech, Inc. by calling 410-666-3200 in Maryland or 804-752-3450 in Virginia. Or, stop by the website at https://flowtechonline.com.

Saturday, May 18, 2019

Demonstration of Techniques Used to Mitigate Industrial Explosions and Overpressure Situations


There’s a number of different things that happen with an overpressure event or explosion at an industrial facility. Some are minor. Some are catastrophic. Improved industrial safety can start with something as small as paying careful attention to a speck of dust. Fike’s Combustion Test Lab offers comprehensive explosibility dust testing, providing invaluable data that ultimately helps protect lives and assets.

In August of 2018 an international audience of students, professors and other experts came together at the International Symposium on Hazards, Prevention and Mitigation of Industrial Explosions (ISHPMIE).  Fike Corporation, recognized globally as the most trusted producer of risk mitigation products, presented innovations and solutions at the Combustion Test Lab. This video highlights the demonstrations where a wide variety of overpressure and explosive situations were neutralized using specialized Fike equipment.

The kinds of events that were demonstrated were:
  • Open Air Deflagration
  • Explosion Venting (far right side of screen)
  • Flameless Venting (Fike's Flamquench product)
  • High Rate Discharge (Fike's HRD explosion suppression product)
  • Explosion Suppression (yellow cube with clear panes)
  • Active Isolation (Chemical and Mechanical)
  • Passive Isolation
  • Pressure Relief (featuring Fike's RD500 Atlas rupture disc)
  • Dust Collector Strength-of-Enclosure Test
  • Active Conveyance
  • Metal Dust Deflagration
For more information on Fike products and capabilities, contact Flow-Tech, Inc. by calling 410-666-3200 in Maryland or 804-752-3450 in Virginia. Or, stop by the website at https://flowtechonline.com.

Tuesday, May 7, 2019

Steam Use Measurement Presents Unique Challenges for Colleges and Universities

Steam poses a unique challenge for colleges and universities.

Many schools want to accurately track, and then internally bill, for steam usage in each of their buildings as part of a wider effort to improve resource management. However, traditional steam metering technologies tend to be a less than optimal choice.

Most times, it’s necessary to place campus steam meters in the basements of buildings where there isn’t a lot of room for piping. That causes issues because flow meters typically require significant runs of straight pipe upstream and downstream of the meter to work correctly.

School administrators also encounter issues by trying to measure steam usage during the low-demand summer months. Common vortex meters, which contain a shedder bar mounted across the diameter of a pipe to measure flow, work well at higher flows. When it comes to low flows, however, they can stop working completely (i.e., low flow cutoff problems). Differential pressure (DP) flow meters coupled with the proper electronics, by comparison, can push the low flow cutoff value downward. However, most DP meters can’t get around the straight-run requirements.
ExactSteam™ V-Cone® Flowmeter
The ExactSteam™ Solution

McCrometer’s ExactSteam solution is designed to overcome those hurdles.

The ExactSteam V-Cone Flowmeter works well with short straight-pipe runs, so it addresses the lack of space issues faced by colleges and universities. It also measures steam across the entire range, performing better at lower flows.

The High Cost Of Low Flow Cutoff

Steam system operators can pay a steep price for generating product that passes through a meter but fails to get measured. Also known as low flow cutoff, those losses are a function of the turndown ratio of flow meters. The ratio — defined as the maximum measurement capability of a device compared to its minimum — dictates how wide a flow spectrum can be measured. On campuses, this creates a major issue because demand for steam in the colder weather can be extremely high compared to off-peak times.

McCrometer’s ExactSteam
ExactSteam™ V-Cone® Flowmeter
ExactSteam is a DP-style flow meter that can be adjusted for colleges during winter months. It contains McCrometer’s established V-cone flow meter combined with a newer electronics package to aid in the downward adjustment of the turndown ratio. A growing number of college campuses, especially larger schools, are seeing the benefits of ExactSteam and adopting the technology.

Some examples include:

Case Study #1 - An East Coast University Steam Operation

This school designed its system to measure from 84,000 lbs/hr to 8,400 lbs/hr, which accounted for a 10:1 turndown ratio and velocities of 420’/second to 42’/second. After the meter was installed, system operators determined their actual flow range was 20,000 lbs/hr to 1,000 lbs/hr (a 20:1 turndown ratio) and velocities were 100’/second to 5’/second.

Because flow rates were overstated, the university dropped below the low flow cutoff and wasn’t measuring at all during the off-season.

The solution: Purchase another meter with a larger cone that would produce more differential pressure at the correct flows. The school has since installed an ExactSteam V-Cone Flowmeter.

Case Study #2 – A University Hospital Using Both Condensate And Steam Meters

During the winter, the steam meters were always measuring more steam than the condensate meters.  The difference was justified because the condensate meters were not capturing steam usage of the autoclaves.  However, during the summer, the condensate meters were measuring more than the steam meters, which was impossible.

The steam meter was designed for flows from 14,000 lbs/hr to 1,400 lbs/hr.  During the summer months the hospital flows frequently dropped below 1,400 lbs/hr, which was below the low flow cutoff.  It was also determined that their highest flow during the summer was 5,000 lbs/hr.  The hospital needed more turndown and a lower flow range.

The solution: The ExactSteam V-Cone Flowmeter was installed.  It was designed for flows from 6,000 lbs/hr to 300 lbs/hr and was able to fit in the basement between two elbows.

Well Positioned For Campus Use

Key aspects of McCrometer’s ExactSteam solution include: a complete flow meter for steam metering, factory-configured for energy metering or mass flow; the ability to measure saturated (dry), superheated, and unsaturated (wet) steam; the V-Cone acts as its own flow conditioner by disrupting all centralized flow disturbances; signal stability allows it to measure a wider range of flow than other meters, minimizing pressure loss; and minimum installation requirements, so retrofitting and new installations are easier.

Because of the inherent conflicts, traditional steam metering technologies are not a good fit for many colleges and universities. However, there are solutions available to campus steam system operators to capture readings from most — if not all — of their steam production, even in less than ideal conditions.

For more information on all aspects of flow measurement and campus metering, contact Flow-Tech, Inc. by calling 410-666-3200 in Maryland or 804-752-3450 in Virginia. Or, stop by their website at https://flowtechonline.com.

Reprinted with permission from McCrometer.

Wednesday, April 24, 2019

Facility Energy Management and Optimization with Precision Ultrasonic Flow & Thermal Energy Meters

Campus energy management
The controlling, balancing, and monitoring of thermal energy flows is of utmost importance in times of rising energy prices, environmental regulations and financial benefits of energy efficient buildings.

FLEXIM, the leading manufacturer of non-intrusive, clamp-on ultrasonic flowmeters, offers thermal energy meters that make it easy to implement a system for more energy efficient buildings and facilities.


FLEXIM’s energy meters combine the attributes of non-intrusive ultrasonic flow measurement with superior temperature monitoring into an integrated energy computer. All flow transducers and temperature sensors are connected to one unit.

Precision Ultrasonic Flow & Thermal Energy Meter
Click for larger view.
Applications/Uses
  • Chiller Plants
  • Heating Plants
  • HVAC
  • Metering & Verification
  • Retrofits
  • Billing
  • Water Control / Leak Detection
  • Combined Heat and Power / Cogeneration Plants