Sunday, January 31, 2016

Grain Silo and Hopper Level Sensors

Here is a short video displaying Nivelco level instruments being used on grain silos and hoppers.

Nivelco manufactures level measurement and control products, specifically level transmitters, using microwave, guided wave radar, ultrasonic, capacitive, and magnetostrictive technologies as well as level switches utilizing float, conductive, magnetic, and vibrating technologies.

For more information, contact:

Arjay Automation
1178 E. Cliff Road
Burnsville, MN 55337-1577
Phone (800) 761-1749
Fax (612) 861-4292

Improving Temperature Measurement Accuracy

temperature transmitter
Temperature transmitter
(courtesy of Moore Industries)
For many temperature applications, getting a high level of accuracy is vital. This white paper highlights how plant and site engineers can ensure the most accurate temperature measurement for critical applications. It shows how to select the best sensor for a particular application and ways to improve the accuracy of the sensor you choose. In particular, it details the reasons why 4-wire RTD sensors are almost always the best choice for high-accuracy temperature applications.

Asset Condition Monitoring Reduces Unplanned Outages, Improves Profitability

asset condition monitoring
Case in point: Wind turbines rely on condition monitoring.
Lost production and unplanned outages cost millions. 

Asset condition monitoring, as the name implies, is the process of continually monitoring a machine or piece of equipment with the intent to predict mechanical wear and / or a failure point. Key indicators of failing equipment are changing values in vibration, noise, and temperature measurements. Monitoring these variables are key indicators of the condition of the machine. By evaluating trends in the data, intelligent systems can provide health information about the equipment and asset in the early detection of possible faults or failures.

Rack-based online condition monitoring solution
Rack-based online condition
monitoring solution
(Bently Nevada)
Implementation of asset condition monitoring are benefiting manufacturing plants and process industries such as chemical, petrochemical, pup & paper, power generation, wind turbines, and oil & gas. Not only can it save money from protecting against unplanned outages, but condition monitoring also improves productivity, quality, and profitability.

GE's Bently Nevada 3500 Monitoring System provides continuous, online monitoring suitable for machinery protection and asset condition monitoring applications. It represents our most capable and flexible system in a traditional rack-based design and offers numerous features and advantages not provided in other systems.

Thursday, January 14, 2016

The Principle Behind the Coriolis Mass Flow Meter

ROTAMASS Coriolis mass flow meter
Coriolis mass flow meter
(courtesy of Yokogawa)
Have you ever witnessed this phenomenon? When a hose filled with water swings but it does not twist. But when the water flow is turned on and the water is forced through the swinging hose, the hose twists as a result of the changing angular velocity in the curved hose. That's the Coriolis effect in action.

Coriolis flowmeters are good for nearly all fluids, including high viscosity liquids, slurries and multi-phase media with a certain gas content.  Mass flow outputs from Coriolis meters have been know to be sensitive to gas bubbles in liquids,  but some designs have a special sensor that can tolerate a relatively high levels of gas in the process media.

The Yokogawa Rotamass operates on this principle. For practical exploitation of this principle it is sufficient for the two measuring tubes to perform oscillations on a small section of a circular path.  This is achieved by exciting the measuring tubes with an electromagnetic exciter in its first resonance frequency.

When no mass is flowing the 2 tubes oscillate symmetrically. But when a mass flows through the tubes, the tubes deform proportionally to the mass flow rate. This deformation is registered by two sensors, and forms the basis of the measuring result. A phase shift occurs between the first and the second sensor. The mass flow rate is derived from this phase difference. Should further the density of the media need to be determined, it is simply computed by evaluation of the oscillation frequency of the measuring tubes. With a single Coriolis device you can measure, simultaneously, mass flow density and temperature providing consistently top-notch measuring precision even amid changing media in process conditions.

See the video blow for a better understanding of how Coriolis mass flow meters operate.