A Better Solution for Open Channel Flow Measurement

Open channel flow instruments require accurate measurement of the surface level of a liquid. A flume, channel or structure which has a known characteristic flow per measured head, together with the measured liquid level, accurately define the flow rate through the system.

Hawk transducer for water applications.

Traditional systems use a stilling well and pressure level measurement system to measure the liquid level in the structure. Sedimentation and buildup will over time cover the sensing part of a pressure measurement system, leading to inaccurate or completely failed measurement. Buildup can also block passages to a stilling well, making any level measurement inaccurate or false. Regular cleaning of measurement systems and stilling wells is required to ensure operation.

The level instrumentation control manufacturer Hawk Measurement uses a non-contact Acoustic Wave sensor, positioned directly over the channel or flow structure, or above the stilling well if required, to provide maintenance free, reliable measurement of the liquid level.

The Hawk Sultan Flow instrument calculates flow through a range of standard measurement structures, and can also be individually tailored to a non-standard flow characteristic. Measurements are temperature compensated, and sensors are available covering a broad range of water, waste-water, irrigation and environmental monitoring applications.

Powerful measurement pulses keep sensor facings clean from moisture and condensation, ensuring maximum performance in all conditions. Continuous and switched outputs are included, as well as local totalizing of flow, and the ability to provide pulsing outputs per flow volume to external counting devices.

For more information, contact Power Specialties, Inc. Call them at (816) 353-6550 of visit their site at https://powerspecialties.com.

  

Happy Independence Day from Power Specialties!

US Power Grids, Oil and Gas Industries, and Risk of Hacking

A report released in June, from the security firm Dragos, describes a worrisome development by a hacker group named, “Xenotime” and at least two dangerous oil and gas intrusions and ongoing reconnaissance on United States power grids.

Multiple ICS (Industrial Control Sectors) sectors now face the XENOTIME threat; this means individual verticals – such as oil and gas, manufacturing, or electric – cannot ignore threats to other ICS entities because they are not specifically targeted.

The Dragos researchers have termed this threat proliferation as the world’s most dangerous cyberthreat since an event in 2017 where Xenotime had caused a serious operational outage at a crucial site in the Middle East. 

The fact that concerns cybersecurity experts the most is that this hacking attack was a malware that chose to target the facility safety processes (SIS – safety instrumentation system).

For example, when temperatures in a reactor increase to an unsafe level, an SIS will automatically start a cooling process or immediately close a valve to prevent a safety accident. The SIS safety stems are both hardware and software that combine to protect facilities from life threatening accidents.

At this point, no one is sure who is behind Xenotime. Russia has been connected to one of the critical infrastructure attacks in the Ukraine.  That attack was viewed to be the first hacker related power grid outage.

This is a “Cause for Concern” post that was published by Dragos on June 14, 2019. 

“While none of the electric utility targeting events has resulted in a known, successful intrusion into victim organizations to date, the persistent attempts, and expansion in scope is cause for definite concern. XENOTIME has successfully compromised several oil and gas environments which demonstrates its ability to do so in other verticals. Specifically, XENOTIME remains one of only four threats (along with ELECTRUM, Sandworm, and the entities responsible for Stuxnet) to execute a deliberate disruptive or destructive attack.

XENOTIME is the only known entity to specifically target safety instrumented systems (SIS) for disruptive or destructive purposes. Electric utility environments are significantly different from oil and gas operations in several aspects, but electric operations still have safety and protection equipment that could be targeted with similar tradecraft. XENOTIME expressing consistent, direct interest in electric utility operations is a cause for deep concern given this adversary’s willingness to compromise process safety – and thus integrity – to fulfill its mission.

XENOTIME’s expansion to another industry vertical is emblematic of an increasingly hostile industrial threat landscape. Most observed XENOTIME activity focuses on initial information gathering and access operations necessary for follow-on ICS intrusion operations. As seen in long-running state-sponsored intrusions into US, UK, and other electric infrastructure, entities are increasingly interested in the fundamentals of ICS operations and displaying all the hallmarks associated with information and access acquisition necessary to conduct future attacks. While Dragos sees no evidence at this time indicating that XENOTIME (or any other activity group, such as ELECTRUM or ALLANITE) is capable of executing a prolonged disruptive or destructive event on electric utility operations, observed activity strongly signals adversary interest in meeting the prerequisites for doing so.”

Creating a Calibration Curve with the CHINO IMRA Infrared Multi Analyzer

The CHINO IMRA on-line multi IR wavelength analyzer utilizes infrared absorption technology to measure moisture, film-thickness, organic properties, and coating-thickness in real time. Signal processing capabilities are built into the compact, stand-alone detector unit for easy installation and operation. A maximum of 99 calibration curves can be stored into the detector memory for numerous measurement applications. This video demonstrates how to create a calibration curve. In this demonstration, moisture content is measured in sand. 

For more information about CHINO moisture, film-thickness, organic properties, and coating-thickness analyzers, contact Power Specialties, Inc. by calling (816) 353-6550 of visit their website at https://powerspecialties.com.

Rotameters a.k.a Variable Area Flow Meters

Rotameter
(Yokogawa)

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 in different situations. 

The post will highlight the workings of rotameters, also known as a variable area flow meter.

Rotameters: An Overview 

Invented by German inventor Karl Kueppers in 1908, rotameters measure the volumetric flow rate of liquids and gases. The device was so named because it functions by rotating in a tube. 

Important elements of a rotameter include the tube and the float. 

The tube is fixed vertically and liquid is fed from the bottom. The fluid is fed from the bottom that 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. 

Every float position shows a specific flow rate for the viscosity and density of a liquid. The device helps in determining the flow rate by matching the position of the float to a scale on the rotameter. The flow can be adjusted manually using a built-in valve. 

Types of Rotameters 

Rotameters can be categorized by the type of tube. A sharp metering edge is located on the float from where the reading is observed by a scale on the tube. The connections and end fittings of the various types of rotameters are different. 

Glass Rotameter

Glass rotameters
(Yokogawa)

The basic glass rotameters consist 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 temperature and pressure. 

Flow rate is determined by the spring and piston combination of the rotameter. The materials and fittings should be chosen as per the temperature and pressure of the liquid. 

Metal Rotameter

Metal tube rotameters are another type that is suitable for temperatures and pressures beyond the glass tubes. They are generally manufactured of stainless steel, aluminum, and brass. The piston position is determined by the mechanical and magnetic followers that can be read from the outside of
the tube. 

Metal rotameter
(Yokogawa)

The meters are generally used for steam applications where glass tube rotameters are not suitable. They are also suitable in situations where other forces would damage the glass metering tubes. 

Industrial Applications of Rotameters

The use of rotameter extends across different industries. The device is extensively used in industries since its an economical way to measure a range of flow rates in almost any conditions. 

Sample Process Analysis 

Rotameters are widely used in sample process analysis. A device with 4 to 20 mA output is used to measure the flow of a sample system. Monitoring the flow rate ensures that the system does not become plugged that could result in big problems. The device can indicate when the flow starts to drop so that the maintenance crew can address the problem before it results in major damage. 

Transport of Liquid Natural Gas 

LNG must be re-gasified during transport to prevent system overpressure that could cause major damage to the storage system. Rotameter can measure the flow rate of vented vapor even at very low temperature. They are ideal for determining the LNG flow rate during transport due to being low cost and providing an accurate reading. 

Rotating Equipment 

Rotameters are also used in measuring the flow of liquid in large rotating equipment. They are used to measure the flow rate of dry gas, coolants, lubricant fluids to ensure safe operations. The device helps in monitoring of coolant flows a lube oil. The flow can be measured continuously due to the use of 4— 20 mA transmitting rotameters.  

Benefits of Rotameters

Rotameters, or variable area flow meters are cost-effective for use in different industrial applications. The price and low maintenance of the device contribute to significant savings for industrial concerns. 

Another advantage of rotameters is that no external power is required. They are mechanical device and no external power source is required to measure the flow rate. This makes it possible for the device to be used in remote and hazardous areas where installing an external power supply can be costly. 

The design of the rotameter allows not the only the measurement of fluid flow but also determine the quality of the liquid. The crew members can see whether the fluid is dirty thereby requiring a change of filter. They can also know whether bubbles are present in the liquid and also whether the liquid is of the correct color. 

Rotameters can be installed along with other flow measuring devices to ensure accurate readings. The device can continuously determine an accurate flow rate. They are simple to install and easy to maintain. Just connect the process line to rotameter’s inlet and outlet pipe. That’s why they are commonly used in many industries where it’s critical to accurately measure the flow rate of the liquid. 

Contact Power Specialties, Inc. with any questions regarding the use of rotameters. Call them them at (816) 353-6550 or visit https://powerspecialties.com.

Today We Honor Those Who Sacrificed Everything for Our Freedom

Understanding the Operation of Coriolis Flow Meters

Coriolis flow meter (Yokogawa ROTAMASS)

The Coriolis patents for industrial application were filed back in the 1950s, and the first Coriolis flow meter was introduced in the 1970s. The device can accurately measure the density, mass flow, volumetric flow, and temperature of almost all types of fluids.

Coriolis flow meters are used in a variety of industries ranging from oil and gas, petrochemicals, and food to chemical, life sciences, and — particularly — in transfer applications.


How Does a Coriolis Flow Meter Work?

Coriolis flow meters work on the principle of Coriolis Force that was first explained by a French engineer and mathematician Gaspard-Gustave de Coriolis in the 19th century.  The Coriolis force represents an inertial force that acts on bodies in a rotating frame of reference.

Also known as inertial mass flow meters, Coriolis flow meters measure fluid flow through inertia. The device has one or more measuring tubes that vibrate due to the force produced by an actuator. The twisting force inside the measuring tube is directly proportional to the mass flow of the liquid.

Measurement Principle of the Coriolis Flow Meter (1)
(courtesy of Yokogawa)

Coriolis meters have sensors inside the measuring flow tube made of magnet and coil assemblies. The sensors are located both at the inlet and outlet of the tube. A voltage in the form a sine wave is created as the coils move through the magnetic field.

The sine waves are in phase with each other when there is no liquid flow. Once the liquid flows through the tube, the measuring tubes twist depending on the mass flow. The sensors detect the extent of the twist by assessing the phase shift in the sine waves. The difference in phase shift helps in determining the mass flow rate.

Volumetric flow is determined by dividing the mass flow rate by the density of the liquid.

Density change is determined by assessing the change in oscillation frequency in response to the excitation inside the tube. The higher the mass flow rate, the lower will be the frequency change and density of the liquid flow.

Measurement Principle of the Coriolis Flow Meter (2)
(courtesy of Yokogawa)

Lastly, Coriolis flow meters can also be used to measure the temperature inside the tube. The device has sensors inside the tube that can detect temperatures of up to 752 F or 400 C.

The Pros and Cons of Coriolis Flow Meters  

Coriolis flow meters can assess liquid flow in both forward and reverse directions. Advanced Coriolis meters have dual curved tubes that can measure with more accuracy. Moreover, the device with curved tubes is characterized by lower pressure drop, making them ideal in specific situations such as wastewater handling, chemical processing, pulp and paper processing, and oil and gas industries.

Another application of Coriolis flow meters is in the pharmaceuticals and food and beverage industries. They can be used with a straight tube design so they are easy to clean. The flow meters are also used in scientific studies for measuring corrosion and assessing liquids and gases. In addition, the flow meters are used in mining operations to monitor liquid flow rate.

While Coriolis meters allow accurate assessment of fluid flow, they are not free from errors. The device can show inaccurate reading when air bubbles are present. The bubbles create splashing that results in generate inaccurate readings. They change the energy required for tube oscillation, resulting in a false assessment of fluid flow.

A lot of energy is spent in the vibration of the tube, especially in case of large spaces. This can also result in failure of accurate assessment of liquid flow inside the tube.

Installation and Calibration of Coriolis Flow Meter

Coriolis flow meter must be installed with full liquid so that no air gets trapped inside the tube. The meter should also be drained completely before use. The ideal location for the flow meter is a vertical pipe mount with an upward flow of fluid.

The Reynolds number is not a limitation with the Coriolis meter. In addition, there is no need for accounting for swirl and velocity profile distortion. As a result, the device can be used without adjusting for straight runs of relaxation piping to condition the liquid flow.

An air release upstream of the meter should be installed if there is a likelihood of air bubbles. In addition, filters, strainers, or air/vapor eliminators can help prevent air bubbles inside the tube. Control valves can also be installed to increase the back-pressure and reduce the likelihood of flashing.

For more information on Coriolis flow meters contact Power Specialties by calling (816) 353-6550 or by visiting https://powerspecialties.com.