Showing posts with label magnetic level indicator. Show all posts
Showing posts with label magnetic level indicator. Show all posts

How Do Magnetic Level Indicators Work?

Magnetic Level IndicatorMagnetic Level Indicators also known as MLIs, have revolutionized the global visual indication market by offering a safer, reliable, and high-visibility alternative to common gauge glass assemblies.  They provide high-visibility representation of the liquid level in a vessel. MLIs can be mounted to tanks in a number of different ways. The most popular configuration, however, is called a side-mount.

The Magnetic Level Indicator (MLI) working principle is widely used in many industrial level applications. The operating principle behind a magnetic level indicator is that the MLI shares the same process fluid as the vessel, and therefore shares the same level.

The three primary components to a Magnetic Level Indicator are:
  • The float
  • The chamber
  • The visual indicator

Magnetic Level IndicatorThe float (contained within the chamber) interacts with the externally mounted visual indicator. As liquid rises and falls in the vessel and MLI chamber, the float follows. The magnets in the float interact with magnets inside each indicator flag. As the float rises and falls in the chamber, the magnets slowly turn each flag 180 degrees. This allows the visible flag color to change to a high-contrasting, highly-visible representation of liquid level.



Magnetic Level Indicator



Utilizing a combination of proven buoyancy principles along with the benefits magnetism, MLIs can be customized to fit virtually any process connection arrangement on the vessel.

The chamber and magnetic float is available in a variety of materials and pressure ratings to accommodate the wide variety of complex process applications present in the world’s major industrial facilities.

Areas Where Magnetic Level Indicator Are Applied:

  • Feed water heaters and boilers
  • Refinery and chemical industries
  • Energy and power plant technology
  • Pulp and paper applications
  • Oil and gas industries
  • Gas plants
  • Pipeline compressor applications
  • Pharmaceutical applications
  • Food and beverage applications

For more information about Magnetic Level Indicators (MLI's), contact Miller Energy by calling 800-631-5454 or visit their web site at https://millerenergy.com.

Selecting the Right Magnetic Level Indicator

Companies in the process industry need the ability to visually monitor liquid levels in vessels (boilers, storage tanks, separators, etc.). Traditionally, armored glass sight gauges have been used. However, many companies want an alternative to sight gauges to avoid problems such as breakage, leaks, or bursting at high pressures and temperatures. In addition, the visibility of the sight glass can be poor and often affected by moisture, corrosion, or oxidation.

Many companies are increasing the use of automation and desire a 4–20 mA, HART®, FOUNDATION® fieldbus, or other output for level—which is difficult to do with a sight glass. Magnetic level indicators (MLIs) do not have the shortcomings of glass sight gauges and are suitable for a wide variety of applications.

Orion Instruments, a Magnetrol company, has authored an excellent Magnetic Level Indicator selection guide.


Miller Energy, Inc.
https://millerenergy.com
In NY/NJ 800-631-5454
In Eastern PA 888-631-5454

Magnetic Level Indicators

magnetic level gauge magnetic level indicator
Configurations of magnetic level gauges
Image courtesy Orion/Magnetrol
Fluid process control operations often involve vessel or tank storage of liquids. Continuous and accurate indication of the liquid level within the tank is an essential data point for process control decision making and safety. Several methods and instrument types are available for tank level measurement, each with its own set of attributes that may be advantageous for a particular installation. Selection criteria for a tank liquid level indicator may include:
  • Direct or indirect measurement of level
  • Level measurement accuracy and reliability
  • Tank shape, regular or irregular
  • Media compatibility with measurement device
  • Requirements for maintenance or calibration
  • Compatibility with process temperature and pressure range
  • Local display and visibility
  • Level indication signal type and transmission
  • Level alarm switches or other indicators
The selection of a magnetic level indicator, also referred to as a magnetic level gauge, for the project will likely be based upon at least one of the instrument's strengths. Magnetic level gauges have a host of potentially positive features for level indication.
  • Continuous level measurement
  • Operable without electric power
  • Direct visual tank fluid level indication, regardless of tank shape or profile.
  • Wide range of operating temperature and pressure
  • Breakage resistant construction
  • Range of construction materials available to accommodate corrosive media
  • Measuring indicators, switches, and transmitters mounted externally, without contacting the medium being measured.
  • Low maintenance operation.
  • Readable level indication from greater distance than glass sight gauges.
  • Applicable to large fluid level ranges with a single instrument.
Magnetic level indicators have a strong position in the tank liquid level measurement field and should be considered as a candidate for fulfilling those application requirements. There are many options available to customize the level indicator for each specific application. I have included a technical data sheet from Orion Instruments, a manufacturer of level instrumentation, for more detail. Share your application challenges with a sales engineer that specializes in level measurement. Combining your process knowledge with their product application expertise will yield positive solutions.


Eliminate Glass Tube Level Gauge Maintenance Costs


Magnetic Level Indicators
Courtesy Orion Instruments
Industrial process control often requires the accurate measurement of liquid level within a tank or other vessel. There are numerous device technologies and vendors from which to choose. A recent post on this blog detailed one of the available methodologies, the magnetic level indicator. I urge you to review that short post to familiarize yourself with the operating principles and advantages of applying a magnetic level indicator, not only on future projects, but as a possible replacement of some of your existing level indication instruments.

Orion Instruments, a Magnetrol company, has authored a case study showing how the replacement of glass tube level gauges with magnetic level indicators can reap substantial cost savings over the product lifetime. The case study, included below, takes but one minute of your time to read, and delivers a compelling incentive to consider magnetic level indicators (MLI) for your new projects, even as cost saving replacements for existing glass tube level gauges.

Read the case study. Contact a product specialist to discuss your application for new or replacement level indicators.