Magnetic Flowmeters: Principles and Applications

Magnetic flowmeters are well suited for flow measurement
with conductive fluids.
Image courtesy Yokogawa

Fluid process control operations rely on the operator's ability to accurately determine qualities and quantities of liquid or gaseous materials. In terms of appraising and working with fluids (such as liquids, steam, and gases) the flowmeter is a staple tool, with the simple goal of expressing the delivery of a subject fluid in a quantified manner. Measurement of media flow velocity can be used, along with other inputs, to determine volumetric or mass flow. The magnetic flowmeter, also called a magmeter, is one of several technologies used to measure fluid flow.

In general, magnetic flowmeters are sturdy, reliable devices able to withstand hazardous environments while returning accurate measurements to operators of a wide variety of processes. The magnetic flowmeter has no moving parts. The operational principle of the device is powered by Faraday’s Law, a fundamental scientific principle stating that a voltage will be induced across any conductor moving at a right angle through a magnetic field, with the voltage being proportional to the velocity of the conductor. The principle allows for an inherently hard-to-measure quality of a substance to be expressed via the magmeter. In a magmeter application, the meter produces the magnetic field referred to in Faraday’s Law. The conductor is the fluid. The actual measurement of a magnetic flowmeter is the induced voltage corresponding to fluid velocity. This can be used to determine volumetric flow and mass flow when combined with other measurements.

The magnetic flowmeter technology is not impacted by temperature, pressure, or density of the subject fluid. It is however, necessary to fill the entire cross section of the pipe in order to derive useful volumetric flow measurements. Faraday’s Law relies on conductivity, so the fluid being measured has to be electrically conductive. Many hydrocarbons are not sufficiently conductive for a flow measurement using this method, nor are gases. On the other hand, water and aqueous solutions tend to exhibit sufficient conductivity to apply magmeter technology.

Magmeters apply Faraday’s law by using two charged magnetic coils; fluid passes through the magnetic field produced by the coils. A precise measurement of the voltage generated in the fluid will be proportional to fluid velocity. The relationship between voltage and flow is theoretically a linear expression, yet some outside factors may present barriers and complications in the interaction of the instrument with the subject fluid. These complications include a higher amount of voltage in the liquid being processed, and coupling issues between the signal circuit, power source, and/or connective leads of both an inductive and capacitive nature.

In addition to salient factors such as price, accuracy, ease of use, and the size-scale of the flowmeter in relation to the fluid system, there are multiple reasons why magmeters are the unit of choice for certain applications. They are resistant to corrosion, and can provide accurate measurement of dirty fluids – making them suitable for wastewater measurement. As mentioned, there are no moving parts in a magmeter, keeping maintenance to a minimum. Power requirements are also low. Instruments are available in a wide range of configurations, sizes, and construction materials to accommodate various process installation requirements.

As with all process measurement instruments, proper selection, configuration, and installation are the real keys to a successful project. Share your flow measurement challenges of all types with a process measurement specialist, combining your own process knowledge and experience with their product application expertise to develop an effective solution.

New Fluid System Connectors From Miller Energy

One of the many series of quick connect hose couplings
from Parker
Image courtesy of Parker Hannafin

Miller Energy now distributes the Parker line of fittings, couplings, quick connects, and hose products for commercial and industrial applications. The addition of this well known and respected brand to the company's product portfolio enables Miller Energy to serve a wider array of customer needs, as well as integrate the new products with its other process measurement and control products to deliver complete, ready to install, solutions for many applications.

An overview of the quick coupling products, just a part of the new product offering, is provided below. To find out more, contact Miller Energy directly and share your hydraulic, pneumatic, and fluid handling requirements and challenges. Leverage your own knowledge and experience with their product application expertise to develop effective solutions.

Quick Coupling Products Guide - Commercial & Industrial from Miller Energy, Inc.

Miller Energy Expands Product Offering

Miller Energy is now a distributor of Asco solenoid
valves for a wide range of general and special applications

Miller Energy, through its acquisition of a New Jersey based distributor, has greatly expanded the company's offering of solenoid valves, pneumatic system components, and fluid handling and control components.

A solenoid is an electrical device, converting electrical energy input to a linear mechanical force. Solenoids are used to provide rapid two state mechanical movement of other devices. In process control applications, those devices are often fluid control valves.

At the basic level, a solenoid is an electromagnetic coil and a metallic rod or arm. Electrical current flow in the coil creates a magnetic field which will position the rod in one of two locations, depending upon whether the coil is energized. The movable component of the solenoid is linked to, or part of, the operating mechanism of another device. This allows the switched electrical output of a controller to regulate mechanical movement in another device and cause a change in its operation. A common solenoid application is the operation of small valves.

A plunger solenoid contains a movable ferrous rod, sometimes called a core, enclosed in a tube sealed to the valve body and extending through the center of the electromagnetic coil. When the solenoid is energized, the core moves to its equilibrium position in the magnetic field. The core is also a functional part of valve operation. It's repositioning causes a designed changed in the valve operating status (open or close). There are countless variants of solenoid operated valves exhibiting particular operating attributes designed for specific types of applications. In essence, though, they all rely on the electromechanical operating principle outlined here.

A solenoid valve is a combination of two functional units.

• The solenoid (electromagnet) described above.
• The valve body containing one or more openings, called ports, for inlet and outlet, and the valve interior operating components.

Flow through an orifice is controlled by the movement of the rod or core. The core is enclosed in a tube sealed to the valve body, providing a leak tight assembly. A controller energizing or de-energizing the coil will cause the valve to change operating state between open and closed, regulating fluid flow. There are almost countless variants of solenoid operated valves, specifically tailored for applications throughout industrial, commercial, and institutional operations.

The document provided below illustrates a portion of the broad array of solenoid valves available for industrial control applications. Share your fluid control requirements and challenges with an application specialist. Leverage your process knowledge and experience with their product application expertise to produce effective solutions.

ASCO Solenoid Valve Product Line Overview from Miller Energy, Inc.

Bulb and Capillary Temperature Switches

General purpose temperature switch with bottom connection
for capillary and bulb specific for each application.
Image courtesy United Electric Controls

Not all processes or operations require the use of state of the art technology to get the desired results. Part of good process design is matching up the most appropriate methods and technology to the operation.

One method of changing the state of a switch in response to a process temperature change is a bulb and capillary temperature switch. The switch operation produces a state change in the mechanical switch when the temperature of a process control operation crosses a certain threshold. Bulb and capillary switches have the advantage of operating without electricity, simplifying their application.

The physical operating principle behind the capillary thermostat relies on the use of a fluid. The fluid inside the thermostat expands or contracts in response to the temperature at the sensing bulb. The change in fluid volume produces a force upon a diaphragm or other mechanical transfer device. The diaphragm is connected to, and changes the status of, an adjoining circuit using a snap action switch. For example, a main use of the operating principle in action is when a commercial food company relies on the capillary switch to control temperature related to processing and distribution. Each individual use of a bulb and capillary thermostat is specifically designed based on manufacturer and industry specifications, all of which apply the same physical principle of fluid based physics.

Because of their simplicity and comparatively modest cost, commercial versions of bulb and capillary switches find application throughout residential and commercial settings. Some common applications include warming ovens, deep fat fryers, and water heaters. The HVAC industry uses capillary and bulb switches because the rate of temperature change found in their applications fits the adjoining range offered by the bulb and capillary type switches. Operation of the temperature switches is subject to a few limitations. The switching point is often fixed, so the application must be without a requirement for an adjustable setpoint. The temperature range over which the switches are suitable is comparatively limited, with a matching of the bulb and capillary fluid system to the application temperature range a necessary task in product selection. Within its proper sphere of use, though, bulb and capillary temperature switches offer simple, reliable operation, with little requirement for maintenance.

Bulb and capillary switches are typically used to evaluate average temperature and are especially useful for applications where the temperature is to be maintained at a well-known, consistent value. The bulb portion can be configured to accommodate mounting within the media to be controlled. The devices can be applied effectively to liquid and gaseous media when the proper bulb is used.

Industrial versions of bulb and capillary switches are fitted with appropriate housings for the installation environment. Hazardous location installation can be accommodated, as well as high current ratings and auxiliary functions. There are almost countless variants of bulb and capillary temperature switches available. Don’t overlook these simple mechanical devices as candidates for application in any temperature control process. Share your application requirements and challenges with product specialists for useful recommendations.

Temperature, Pressure, Vacuum, and Differential Switches from Miller Energy, Inc.

Application of Load Cells in Process Measurement

The advanced model G5 can handle input signals from multiple load cells
Image courtesy of BLH Nobel

In industrial application of process measurement and control, principles of the physical sciences are combined with technology and engineering to create devices essential to modern high speed, high accuracy system operation. Years of research, development, and the forward march of humanity’s quest for scientific knowledge and understanding yields packaged devices for process measurement that are easily applied by system designer and operators.

Load cells are the key components applied to weighing component or processed materials in modern industrial operations. Load cells are utilized throughout many industries related to process management, or just simple weighing operations. In application, a load cell can be adapted for measurement of items from the very small to the very large.

In essence, a load cell is a measurement tool which functions as a transducer, predictably converting force into a unit of measurable electrical output. While many types of load cells are available, one popular cell in multiple industries is a strain gauge based cell. Strain gauge cells typically function with an accuracy range between 0.03% and 0.25%. Pneumatically based load cells are ideal for situations requiring intrinsic safety and optimal hygiene. For locations without a power grid, there are even hydraulic load cells, which function without need for a power supply. These different types of load cells follow the same principle of operation: a force acts upon the cell (typically the weight of material or an object) which is then returned as a value. Processing the value yields an indication of weight in engineering units.

For strain gauge cells, deformation is the applied operational principal, where extremely small amounts of deformation, directly related to the stress or strain being applied to the cell, are output as an electrical signal with value proportional to the load applied to the cell. The operating principle allows for development of devices delivering accurate, precise measurements of a wide range of industrial products.

Load cell advantages include their longevity, accuracy, and adaptability to many applications, all of which contribute to their usefulness in so many industries and applications. A common place to find a strain gauge load cell in use is off a causeway on a major highway at a truck weigh station. Through innovation, load cells have been incorporated in an efficient measuring system able to weigh trucks passing through the station, without having each stop. Aircraft can be weighed on platform scales which utilize load cells, and even trains can be weighed by taking advantage of the robust and dependable nature of the transducers.

Thanks to their widespread incorporation and the sequential evolution of technology, load cells are a fantastically useful tool in process measurement and control. Share your process weighing challenges with application experts, combining your own process expertise with their product knowledge to develop an effective solution.

Product Update: SMARTDAC+ GX/GP Series Recorders & GM Series Data Acquisition System Release 4

Updated SMARTDAC line of data acquisition instruments
Image courtesy Yokogawa

Yokogawa Electric Corporation announced it's Release 4 of the SMARTDAC+® GX series panel-mount type paperless recorder, GP series portable paperless recorder, and GM series data acquisition system.

With this latest release, new modules are provided to expand the range of applications possible with SMARTDAC+ systems and improve user convenience. New functions include sampling intervals as short as 1 millisecond and the control and monitoring of up to 20 loops.

Overview

Recorders and data acquisition systems (data loggers) are used on production lines and at product development facilities in a variety of industries to acquire, display, and record data on temperature, voltage, current, flow rate, pressure, and other variables. Yokogawa offers a wide range of such products, and is one of the world’s top manufacturers of recorders. Since releasing the SMARTDAC+ data acquisition and control system in 2012, Yokogawa has continued to strengthen it by coming out with a variety of recorders and data acquisition devices that meet market needs and comply with industry-specific requirements and standards.

With this release, Yokogawa provides new modules with strengthened functions that meet customer needs for the acquisition and analysis of detailed data from evaluation tests. These modules decrease the cost of introducing a control application by eliminating the need for the purchase of additional equipment.

Enhancements

The functional enhancements available with Release 4 are as follows:

High-speed analog input module for high-speed sampling.

To improve the safety of electric devices such as the rechargeable batteries used in everything from automobiles to mobile devices, evaluation tests must be conducted to acquire and analyze detailed performance data. For this purpose, sampling at intervals as short as 1 millisecond is desirable. However, this normally requires an expensive, high-performance measuring instrument. When the new high-speed analog input module, a SMARTDAC+ system can sample data at intervals as brief as 1 millisecond, which is 1/100th that of any preceding Yokogawa product. This is suitable for such high performance applications such as measurement of the transient current in rechargeable batteries to vibration in power plant turbines. A dual interval function has also been added that enables the SMARTDAC+ to efficiently and simultaneously collect data on slowly changing signals (e.g., temperature) and quickly changing signals (e.g., pressure and vibration).

PID control module for control function

In applications that need both control and recording, such as controlling the temperature of an industrial furnace or the dosage process at a water treatment plant, there is a need for systems that do not require engineering and can be quickly and easily commissioned. In a typical control and monitoring application, a separate recorder and controller is required to control temperature, flow rate and pressure. At the same time, a data acquisition station must communicate with the controller to ensure data is being capture and recorded. It is time consuming and oftentimes confusing, to ensure the controller and the data acquisition station is communicating seamlessly. By combining continuous recording function of the SMARTDAC+ and PID control module into a single platform, customers can now seamlessly control and record critical process data in one system. The SMARTDAC+ can control, monitor and record up to 20 loops. Each PID control module comes with 2 analog inputs, 2 analog outputs, 8 digital inputs and 8 digital outputs.

Four-wire RTD/resistance module for precise temperature measurement

While three-wire RTDs are widely used in many fields such as research institutes to manufacturing, some applications require higher level of precision and accuracy that is only possible with 4-wire RTDs. A 4-wire RTD is the sensor of choice for laboratory applications where accuracy, precision, and repeatability are extremely important. To satisfy this need, Yokogawa has released a 4-wire RTD/resistance module for the SMARTDAC+.

Target Markets

GX series: Production of iron and steel, petrochemicals, chemicals, pulp and paper, foods, pharmaceuticals, and electrical equipment/electronics; water supply and wastewater treatment facilities.

GP series: Development of home appliances, automobiles, semiconductors, and energy-related technologies; universities; research institutes.

GM series: Both of the above target markets.

For more information on the SMARTDAC+ GX/GP Series Recorders & GM Series Data Acquisition System contact Miller Energy at (800) 631-5454 or by visiting the company website.

Electronic to Pneumatic Converter

Component schematic using electronic controller and pneumatic
control valve
Image courtesy of Yokogawa

A straight forward device, the current to pneumatic converter produces a pneumatic output signal that is proportional to an electrical control level input signal of 4 to 20 mA or 10 to 50 mA. This provides a useful interface between electronic controllers and pneumatically operated valves, air cylinders, or other air operated control elements.

Pneumatic signals are regularly used throughout many installations as matter of safety, legacy, or because a pneumatic signal can provide motive power to an operating device such as a valve positioner. Electrical control signals can be transmitted long distances across wires to deliver control signals to operating elements. The current to pneumatic converter provides a bridge between the two systems and allows the most beneficial aspects of each to be brought to bear on process operation.

Converters are available in standard variants that accommodate a number of hazardous location designations, as well as several output pressure ranges and calibrations. Share your process control connectivity challenges with application specialists, combining your own process knowledge and experience with their product application expertise to develop effective solutions.

Current to Pneumatic Converter from Miller Energy, Inc.

WirelessHART Toxic and Combustible Gas Detector

Vanguard WirelessHART toxic and combustible
gas detector for industrial safety use.
Image courtesy United Electric Controls

Earlier this year, United Electric Controls released its Vanguard WirelessHART gas detector for use in a wide range of industrial settings. Detecting potentially hazardous levels of toxic or combustible gases is an essential element of plant safety where these gases are employed. The Vanguard detector integrates seamlessly into existing WirelessHART networks and asset management systems. A battery lifespan of 5 years and a design that provides in-place test and calibration mean there will be little burden to maintaining the proper operation of the unit.

More detail is provided in the brochure included below. The Vanguard incorporates solid construction and design features to deliver ease of use and long service life. Share your gas detection and process measurement challenges with instrumentation specialists. Combining your own process experience and knowledge with their product application expertise will result in an effective solution.

WirelessHART Gas Detector for Toxic and Combustible Gas from Miller Energy, Inc.

Level and Flow Instruments for Hygienic Applications

Magnetrol is a globally recognized leader in the manufacture of flow and level instrumentation for industrial scale applications. The products employ a range of differing technologies to provide measurement precision across an array of challenging applications. The informational piece included below highlights Magnetrol's products intended for use in industries, such as pharma or food processing, where special materials and product design are employed to meet the special requirements of hygienic processing.

Share your flow and level measurement challenges with process instrumentation experts, combining your own knowledge and experience with their expertise to develop effective solutions.

Life Science Applications and Products - Magnetrol from Miller Energy, Inc.

Pump Protection Using Thermal Dispersion Flow Switches

Thermal dispersion flow switches have advantages
when applied for pump protection
Image courtesy Magnetrol

Good practice for installing industrial pumps calls for inclusion of protective devices to assure that the pump is not exposed to conditions beyond its design intent. Monitoring liquid flow is a useful method for determining if a pump is operating within a safe range.

There are numerous methods of verifying flow in piping connected to a pump. Magnetrol, globally recognized manufacturer of flow and level measurement technologies, offers up their assessment of various pump protection measures and a recommendation for what they consider an advantageous choice for flow measurement in a pump protection application.

Magentrol's white paper is included below, and you can share your flow and level measurement challenges with application experts for help in developing effective solutions.

Pump Protection Using Thermal Dispersion Switches from Miller Energy, Inc.

Yokogawa ROTAMASS "Total Insight" Line of Coriolis Flowmeters

In the last decade, the use of Coriolis flow meters has been changing from general purpose to supporting customer needs in specific applications. While the technological complexity increased, the demand for simple operation and handling also grew.

Yokogawa answers these needs by offering six dedicated product lines with two specialized transmitters allowing the highest flexibility - the ROTAMASS Total Insight.

Total Insight

The ROTAMASS philosophy gives Total Insight throughout the whole lifecycle.

To facilitate the implementation of optimal processes and increase the efficiency of personnel, Yokogawa has placed a strong focus on simplifying fundamental operating concepts with Total Insight. The Total Insight concept is built in to the latest generation of Rotamass transmitters and provides enhanced settings for customized setups, predefined trend views, or multiple configuration sets for fast changeover in batch production.

ROTAMASS NANO - When every drop counts

The world's smallest dual bent tube Coriolis flow meter series for highly accurate measurement at lowest flows.

The dual tube design compensates for fluctuations of density, temperature, pressure and environment conditions. This provides a consistent repeatable and accurate measurement especially for small size Coriolis flow meters.

Typical Applications

• Batching
• Dosing
• Blending
• Chemical injection
• Dosing systems
• High pressure gases
• Liquid and gas low flow measurement
• Precision coatings
• Metering pump control
• Metrology
• R&D laboratory
• Vacuum thin film coating

ROTAMASS Prime - Versatile in applications

The favorably priced and versatile Coriolis flow meter with lowest pressure drop in the market. Ideal for a broad range of standard applications, this series is a flexible and cost effective solution for highly accurate flow and density measurements.
Features such as concentration measurement or the Tube Health Check function allow the meter to be adjusted to customer needs.

• Typical Applications
• Batching
• Blending
• Chemical recovery
• Continuous reaction
• In-line concentration and density measurement
• Catalyst feed
• Filling and dosing
• Mass balance
• Net oil computing
• Palm oil
• Process control

ROTAMASS Supreme - Experience meets innovation

The most accurate Coriolis flow meter with industry’s best zero stability.

The successful Rotamass series has been progressively developed and is also newly equipped with

the latest technology. This meter delivers unsurpassed performance for demanding and critical applications with superior aeration handling and advanced diagnostic functionality.

• Typical Applications
• Batching
• Burner control
• Feed and product control
• Filling and dosing
• Gas void fraction
• In-line concentration and density
• Loss control
• Material and mass balance
• Net oil computing
• Process control
• Solvents
• Water cut

ROTAMASS Intense - Safe under high pressure

The Coriolis meter with the most robust and durable design for precise measurement in high pressure applications.

Safety is always a concern and especially when operating at high pressures. Therefore, this series has been designed to meet the highest safety requirements. Combined with advanced diagnosis such as the “Total Health Check” function, operation is always under secure control.

• Typical Applications
• Chemical injection
• Compressed gases
• Fuels
• Glycol TEG/MEG
• High pressure gases
• Hydraulic oil
• Hydrocarbons
• Liquified gases
• Natural gas hydration
• Offshore and onshore
• Oil refinery processes
• Solvents

ROTAMASS Hygienic - With pure dedication

Specifically designed and certified for food & beverage, biotechnology and pharmaceutical utility applications.

This series is the appropriate answer to the daily constraints of hygienic processes ensuring continuous product quality and minimizing losses. This is made easy by the provided multi-variable measurement and various dedicated features.

• Typical Applications
• Bioreactor feeds
• Bottling
• Carbonation of beverages
• Deionized water
• Fermentation
• Juice processing
• Molasses measurement
• Online sugar concentration
• Raw milk tanker unloading
• Process water reclamation
• Product quality control
• Sugar industry

ROTAMASS Giga - Big in performance

Delivering best in class accuracy and most flexible installation at high flow rates.

The unmatched accuracy at the low end of the measuring range offers maximum flexibility from engineering to final operation. This series unifies a long service life with low maintenance costs and reliable performance.

• Typical Applications
• Bitumen
• Distribution networks
• Drilling mud
• LNG
• Rail car loading
• Ship loading
• Truck loading
• Tar
• Offshore and onshore
• Oil well cementing and hydrofracturing

Essential and Ultimate Transmitters

Future Ready. The ROTAMASS TI product family has a common and unified transmitter platform with two options that provide the highest flexibility and a tailor-made solution. The Essential transmitter is the cost effective solution for general purpose applications, and the Ultimate transmitter provides various additional features for best-in-class measurement.

Essential Transmitter

• Wizard for easy setup and guidance through the main configuration
• “Event Management” as unique and useful support to run the process effectively and safely
• Data mobility provided by microSD card for easy transfer to other devices for fast setup or to pc for in-depth process analysis or remote service
• Widest range of I/O combinations in the market for most flexible adjustment to the existing system periphery
• Universal power supply to install the device anywhere in the world
• HART communication

Ultimate Transmitter

• Patented “Tube Integrity” function and “TotalHealth Check” for inline meter verification without disturbing running measurements
• “Features on demand” for easy expansion of special functions via software activation key
• Batching function combined with multiple configuration sets to support fast changeover
• “Dynamic Pressure Compensation” for consistently accurate and stable measurement even with significant fluctuations in operating pressures
• Inline concentration measurement
• Integrated net oil computing acc. API standard

Share your process flow measurement requirements and challenges with application experts, combining your own experience and knowledge with their product application expertise to develop effective solutions.

Sometimes the Simple Solution Is the Best

This metal tube variable area flow meter is reliable,
accurate, and requires little maintenance
Photo courtesy Brooks Instrument

For process control and commercial or industrial applications, there are numerous methods of flow measurement from which to choose. Technologies range from very simple applications of physical principles to deployment of very specialized electronics and sensors. The available range of accuracy, response, and cost is quite broad, with a general expectation that higher cost will deliver better performance and accuracy.

Making the best instrument selection for a flow measurement application should include an assessment of what the operators really need in order to safely and effectively run the process or perform the task related to the measurement of fluid flow. Installing instrumentation with capabilities far beyond what is required is almost certainly a waste of financial resources, but may also have an unexpected impact on operators. Through the generation of data that, while accurate, does not provide any actionable information about process condition, operators can be misled, similar to the occurrence of a false or nuisance alarm. Some applications call for high accuracy, some do not. Define your informational needs and select instruments that will meet those needs.

There is a large array of applications that can be satisfied with simpler, less costly measurement technology. These devices often employ turbines or vanes to produce an indication of flow rate. Incorporated into some of the instruments is a means to visually observe the flowing liquid to verify color and clarity. Simple devices sometimes are intended only to indicate the presence of fluid flow, and whether the flow rate is high or low. Configurations are available that allow insertion into lines under pressure (hot tap) through a full port ball valve. Other variants with combinations of features and capabilities abound.

The selection range is enormous, so define your minimum needs first, then search for a compatible product. Your search can be enhanced by contacting an instrumentation specialist. Combining your process expertise with their broad product knowledge will produce effective solutions.

Metal Tube Variable Area Flow Meter from Miller Energy, Inc.

Heat Processing of Industrial Fluids

Steam produced by gas fired industrial boilers is a
commonly applied means of delivering heat energy

Heat, as an entity, was not always something seen as a partially visible potential indicator of changing weather patterns. The now outdated caloric theory portrayed heat as a measure of an invisible fluid called the caloric, typifying it as a solely physical property. Thermodynamics have surpassed the caloric theory and rendered it obsolete, but the understanding and manipulation of heat in industrial settings, especially pertaining to fluids, is a central part of some of the world’s most important industries. Specifically, the measurement and control of heat related to fluid processing is a vital industrial function, and relies on regulating the heat content of a fluid to achieve a desired temperature and outcome.

The manipulation of a substance’s heat content is based on the central principle of specific heat, which is a measure of heat energy content per unit of mass. Heat is a quantified expression of a system’s internal energy. Though heat is not considered a fluid, it behaves, and can be manipulated, in some similar respects. Heat “flows” from points of higher temperature to those of lower temperature, just as a fluid will flow from a point of higher pressure to one of lower pressure.

A heat exchanger provides an example of how the temperature of two fluids can be manipulated to regulate the flow or transfer of heat. Despite the design differences in heat exchanger types, the basic rules and objectives are the same. Heat energy from one fluid is passed to another across a barrier that prevents contact and mixing of the two fluids. By regulating temperature and flow of one stream, an operator can exert control over the heat content, or temperature, of another. These flows can either be gases or liquids. Heat exchangers raise or lower the temperature of these streams by transferring heat between them.

Recognizing the heat content of a fluid as a representation of energy helps with understanding how the moderation of energy content can be vital to process control. Controlling temperature in a process can also provide control of reactions among process components, or physical properties of fluids that can lead to desired or improved outcomes.

Heat can be added to a system in a number of familiar ways. Heat exchangers enable the use of steam, gas, hot water, oil, and other fluids to deliver heat energy. Other methods may employ direct contact between a heated object (such as an electric heating element) or medium and the process fluid. While these means sound different, they all achieve heat transfer by applying at least one of three core transfer mechanisms: conduction, convection, and radiation. Conduction involves the transfer of heat energy through physical contact among materials. Shell and tube heat exchangers rely on the conduction of heat by the tube walls to transfer energy between the fluid inside the tube and the fluid contained within the shell. Convection relates to heat transfer due to the movement of fluids, the mixing of fluids with differing temperature. Radiant heat transfer relies on electromagnetic waves and does not require a transfer medium, such as air or liquid. These central explanations are the foundation for the various processes used to regulate systems in industrial control environments.

The manner in which heat is to be applied or removed is an important consideration in the design of a process system. The ability to control temperature and rate at which heat is transferred in a process depends in large part on the methods, materials, and media used to accomplish the task. Selecting and properly applying the best suited controls, instruments and equipment is a key element of successful process operation. Share your challenges with application experts, combining your own process knowledge and experience with their product expertise to develop effective solutions.

Valves for LNG and CNG Operations

Valve specially designed for gas extraction operations
has integral bypass which equalizes pressure across the
valve prior to opening the main line, reducing torque
requirements and  piping stress.
Courtesy Habonim

The production and distribution of natural gas presents operators with substantial logistical, safety, and physical challenges. Maintaining flow control, containing, and dispensing of natural gas, CNG, and LNG are hazardous endeavors requiring special equipment configuration throughout the supply chain.

Source and pipeline operations are faced with high pressure and extreme working environments. At various points along the distribution path, valves will be needed to regulate or direct flow and isolate portions of the system for safety or service. Emergency shutdown valves must be configured and installed to provide failure-proof reliability when called upon to operate. Transportation containers and equipment will utilize specialized valves adapted for the pressure, temperature, and reliability requirements of the application and industry. Additionally, some may need to survive fire conditions without failure.

Fueling stations for compressed natural gas employ valves that will endure cold temperatures produced by gas expansion, plus dynamic pressure cycling. Bubble tight shutoff is necessary to maintain safety.

Liquified natural gas (LNG) presents many of the same application challenges as pressurized gas, with the added element of cryogenic temperatures.

All of these applications can be adequately served with a properly selected and configured valve and actuator. Share your fluid flow control and valve challenges of all types with application specialists. The combination of your process knowledge and experience with their product application expertise will produce an effective solution.

Industrial Valves for Gas Distribution, CNG, LNG from Miller Energy, Inc.

Water Quality Analysis – Constituent Survey Part 3

Water quality can be a concern for process input or effluent

What we know as “water” can consist of many non-H2O components in addition to pure water. This three part series has touched on some of the constituents of water that are of interest to various industrial processors. The first installment reviewed dissolved oxygen and chloride. The second article covered sulfates, sodium, and ammonia. 

To conclude the three part series on water quality analysis in process control related industrial applications we examine silica, another element which in sufficient quantities can become a confounding variable in water for industrial use. In natural settings, silica, or silicon dioxide, is a plentiful compound. Its presence in water provides a basis for some corrosion-inhibiting products, as well as conditioners and detergents. Problems arise, however, when high concentrates of silica complicate industrial processes which are not designed to accommodate elevated levels. Specifically, silica is capable of disrupting processes related to boilers and turbines. In environments involving high temperature, elevated pressure, or both, silica can form crystalline deposits on machinery surfaces. This inhibits the operation of turbines and also interferes with heat transfer. These deposits can result in many complications, ranging through process disruption, decreased efficiency, and resources being expended for repairs.

The silica content in water used in potentially affected processes needs to be sufficiently low in order to maintain rated function and performance. Silica analyzers provide continuous measurement and monitoring of silica levels. The analyzers detect and allow mitigation of silica in the initial stages of raw material acquisition or introduction to prevent undue disruption of the process. Additionally, a technique called power steam quality monitoring allows for the aforementioned turbine-specific inhibition – related to silica conglomerates reducing efficacy and physical movement – to be curtailed without much issue. The feedwater filtration couples with a low maintenance requirement, resulting in reduced downtime of analytic sequences and a bit of increased peace of mind for the technical operator.

While silica and the other compounds mentioned in this series are naturally occurring, the support systems in place to expertly control the quality of water is the most basic requirement for harvesting one of the earth’s most precious resources for use. As a matter of fact, the identification and control of compounds in water – both entering the industrial process and exiting the industrial process – demonstrates key tenets of process control fundamentals: precision, accuracy, durability, and technological excellence paired with ingenuity to create the best outcome not just one time, but each time.

New Pulsar R86 Non-contact Radar Level Transmitter From Magnetrol

Magnetrol's new non-contact radar level transmitter,,
Pulsar R86
Courtesy Magnetrol

Level measurement is a part of countless industrial processes and installations. Accurate measurement of contained solids or liquid enhances safety and operational efficiency, both of which contribute to the bottom line.

Magnetrol, globally recognized innovator in flow and level measurement, recently released its latest version of non-contact radar level measuring instruments. The Pulsar R86 transmitter operates in the 26GHz range, delivering a smaller wavelength with improved resolution, smaller antenna, and a narrower beam. Other unique innovations have been incorporated into the instrument to simplify installation and application.

The R86 is suitable for a broad range of applications across almost every industry. On board diagnostics are incrementally advanced to provide best performance and deliver the information needed to maintain proper operation.

The latest information on the Pulsar R86 is included below. Reach out to process measurement specialists and share your measurement challenges and requirements. Combining your own process knowledge and experience with their product application expertise will result in an effective solution.

Magnetrol Non-Contact Radar Level Transmitter Pulsar R86 from Miller Energy, Inc.

Water Quality Analysis – Constituent Survey (Part 2)

Water can contain many contaminants

It would be difficult to understate the role and importance of water in industrial processing, even our own biological existence. In the first installment of this series, the roles of dissolved oxygen and chlorides were covered.

Continuing the examination of water quality monitoring in municipal and industrial processes, another key variable which requires monitoring for industrial water use is sulfate. Sulfate is a combination of sulfur and oxygen, salts of sulfuric acid. Similarly to chlorides, they can impact water utilization processes due to their capability for corrosion. The power generation industry is particularly attuned to the role of sulfates in their steam cycle, as should be any boiler operator. Minerals can concentrate in steam drums and accelerate corrosion. Thanks to advancements in monitoring technology, instruments are available which monitor for both chlorides (covered in the previous installment in this series) and sulfates with minimal supervision needed by the operator, ensuring accurate detection of constituent levels outside of an acceptable range. Ionic separation technologies precisely appraise the amount of sulfate ions in the stream, allowing for continuous evaluation and for corrective action to be taken early-on, avoiding expensive repairs and downtime.

Another substance worthy of measurement and monitoring in process water is sodium. Pure water production equipment, specifically cation exchange units, can be performance monitored with an online sodium analyzer. Output from the cation bed containing sodium, an indication of deteriorating performance, can be diverted and the bed regenerated. Steam production and power generation operations also benefit from sodium monitoring in an effort to combat corrosion in turbines, steam tubes, and other components. Sodium analyzers are very sensitive, able to detect trace levels.

Ammonia is comprised of nitrogen and hydrogen and, while colorless, carries a distinct odor. Industries such as agriculture utilize ammonia for fertilizing purposes, and many other specializations, including food processing, chemical synthesis, and metal finishing, utilize ammonia for their procedural and product-oriented needs. An essential understanding of ammonia, however, includes the fact that the chemical is deadly to many forms of aquatic life. Removing ammonia from industrial wastewater is a processing burden of many industries due to the environmental toxicity.

Methods for removing ammonia from wastewater include a biological treatment method called ‘conventional activated sludge’, aeration, sequencing batch reactor, and ion exchange. Several methods exist for in-line or sample based measurement of ammonia concentration in water. Each has particular procedures, dependencies, and limitations which must be considered for each application in order to put the most useful measurement method into operation.

As water is an essential part of almost every facet of human endeavor and the environment in which we all dwell, the study and application of related analytics is an important component of many water based processes. The variety of compounds which can be considered contaminants or harmful elements when dissolved or contained in water presents multiple challenges for engineers and process operators.

The detection and measurement of water constituents can pose challenges to plant operators. Share your requirements with instrumentation experts, and combine your own process knowledge and experience with their product application expertise to formulate an effective solution.

Water Quality Analysis – Constituent Survey (Part 1)

Water quality analysis is utilized at sewage treatment plants,
but at many other industrial facilities, too.

Of all the raw materials available for human consumption – aside from the air we breathe – the most vital component of life on earth is water. In addition to the global need for humans to drink water in order to survive, the use of water is essential in a myriad of industries relating to process control. Whether the goal is the production or monitoring of pure water for industrial use, or the processing of wastewater, the ability to measure the presence and level of certain chemical constituents of water is necessary for success.

In order to use water properly, industrial professionals combine state of the art analyzers with technical expertise to evaluate water quality for use or disposal. Two essential values of process control are ensuring elements of a control system are accurate and secure, and, furthermore, that they are accurate and secure for each product every time. By properly vetting water in industry, engineers and other personnel in fields such as pharmaceuticals, chemical, food & beverage, brewing, power, and microelectronics are able to maintain standards of production excellence and conform with regulatory requirements related to water quality.

The amount of dissolved oxygen present in water can correlate with the degree of movement at an air-water interface, also being impacted by pressure, temperature, and salinity. Excessive or deficient dissolved oxygen levels in industrial process waters may have an impact on process performance or end product quality. Likely, the most common application for dissolved oxygen measurement is in the evaluation of wastewater for biological oxygen demand. The primary function of dissolved oxygen in wastewater is to enable and enhance the oxidation of organic material by aerobic bacteria, a necessary step in treatment.

To measure dissolved oxygen, specialized sensors and companion instruments are employed that require careful maintenance and trained technical operators. The level of measurement precision varies depending on the industry employing the technology, with numerous applications also being found in the food & beverage and pharmaceutical industries. In-line continuous measurement is used in wastewater processing to determine if the dissolved oxygen remains in a range that supports the bacteria necessary for biodegradation.

Chloride concentration in wastewater is strictly regulated. Industrial and commercial operation effluent can be regulated with respect to allowable chloride content. While commonly found in both streams and wastewater, chlorides, in large amounts, can present challenges to water utilization or processing facilities. Chloride levels impact corrosion, conductivity, and taste (for industries in which such a variable is paramount). In a process system, having an essential component marred due to elevated quantities of a substance could reverberate into any end-product being manufactured. Chloride analyzers, some of which can also detect and monitor other water characteristics, serve as important tools for water consuming facilities to meet regulatory standards for effluent discharge or internal quality standards for recycling.

There are other constituents of what we refer to as “water” that are subject to measurement and monitoring for a range of institutional, industrial, and municipal applications. Those will be explored in the next part of this article series.

Wireless Transmitters In Process Measurement and Control

Wireless industrial temperature transmitter
Courtesy Yokogawa

In process control, various devices produce signals which represent flow, temperature, pressure, and other measurable elements of the process. In delivering the process value from the measurement point to the point of decision, also known as the controller, systems have traditionally relied on wires. More recently, industrial wireless networks have evolved, though point-to-point wireless systems are still available and in use. A common operating protocol today is known as WirelessHARTTM, which features the same hallmarks of control and diagnostics featured in wired systems without any accompanying cables. Other wireless standards are employed in industrial settings, as well.

Wireless devices and wired devices can cohabitate the same network. The installation costs of wireless networks are decidedly lower than wired networks due to the reduction in labor and materials for the wireless arrangement. Wireless networks are also more efficient than their wired peers in regards to auxiliary measurements, involving measurement of substances at several points. Adding robustness to wireless, self-organizing networks is easy, because when new wireless components are introduced to a network, they can link to the existing network without needing to be reconfigured manually. Gateways can accommodate a large number of devices, allowing a very elastic range for expansion.

In a coal fired plant, plant operators walk a tightrope in monitoring multiple elements of the process. They calibrate limestone feed rates in conjunction with desulfurization systems, using target values determined experientially. A difficult process environment results from elevated slurry temperature, and the associated pH sensors can only last for a limited time under such conditions. Thanks to the expandability of wireless transmitters, the incremental cost is reduced thanks to the flexibility of installing new measurement loops. In regards to maintenance, the status of wireless devices is consistently transmitted alongside the process variable. Fewer manual checks are needed, and preventative measures may be reduced compared to wired networks.

Time Synchronized Mesh Protocol (TSMP) ensures correct timing for individual transmissions, which lets every transmitter’s radio and processor ‘rest’ between either sending or receiving a transmission. To compensate for the lack of a physical wire, in terms of security, wireless networks are equipped with a combination of authentication, encryption, verification, and key management. The amalgamation of these security practices delivers wireless network security equal to that of a wired system. The multilayered approach, anchored by gateway key-management, presents a defense sequence. Thanks to the advancements in modern field networking technology, interference due to noise from other networks has been minimized to the point of being a rare concern. Even with the rarity, fail-safes are included in WirelessHARTTM.

All security functions are handled by the network autonomously, meaning manual configuration is unnecessary. In addition to process control environments, power plants will typically use two simultaneous wireless networks. Transmitters allow both safety showers and eyewash stations to trigger an alarm at the point of control when activated. Thanks to reduced cost, and their ease of applicability in environments challenging to wired systems, along with their developed performance and security, wireless industrial connectivity will continue to expand.

Share your process measurement and control challenges with knowledgeable professionals, combining your own process knowledge and experience with their product application expertise to develop effective solutions.

Trace Moisture Analyzer

Portable and fixed installation trace moisture analyzers
Courtesy Teledyne Analytical Instruments

Moisture, the presence of water molecules, can impact certain products and processes in undesirable ways. Trace moisture analysis of clean gases can be accomplished using aluminum oxide sensors, one of several technologies available.

Instruments are available for continuous monitoring of moisture levels, or spot checking. Aluminum oxide moisture sensors rely on the change in capacitance within the sensor, which varies with the moisture content.

A concern with aluminum oxide sensor technology is drift associated with temperature and aging. A great degree of this has been alleviated through changes in sensor structure. The technology and instrumentation is easily applied and requires little in the way of maintenance other then periodic calibration.

More detail and explanation of the technology and instruments can be found in the brochure included below. Share your process analytical measurement challenges with experienced product specialists, combining your own process knowledge and experience with their up to date product expertise to develop effective solutions.

Trace Moisture Analyzer For Industrial Use from Miller Energy, Inc.