PROTRAC: Radiation-based level measurement

In radiometric, i.e. radiation-based, level measurement, a slightly radioactive isotope emits focused gamma rays.
The sensor, which is mounted on the opposite side of the vessel, receives this radiation. Since gamma rays are attenuated when penetrating matter, the sensor can calculate level, point level, density or mass flow from the intensity of the incoming radiation.
The advantages
  • Maximum operational reliability even in the harshest environments
  • Measurement is independent of pressure, temperature and product aggressiveness
  • Measuring system can be installed on the outside of a vessel during ongoing production

Step by step to the right sensor

What would you like to measure?




Flexible detector

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Flexible detector with higher accuracy

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Rod detector

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How does radiation-based level measurement work?

Product attenuates radioactive energy, and the detector outputs a level value based on the energy it measures.

Radiometric or radiation-based measurement sounds complicated, but it’s relatively easy to understand. An isotope with low radiating intensity is housed inside source holder on one side of a vessel or pipe. The secure source holder collimates the energy so it is directed only at a detector mounted on the opposite side. As material fills the vessel, less energy reaches the detector which outputs an inferred level measurement. 

What are the advantages of radiometric instruments?

Radiometric sensors are used for continous level and point-level monitoring in the most difficult solids and liquids applications. The reason for this is nuclear gauges provide a non-contact measurement that delivers accurate readings without touching the process material, so there is no chance of damaging the detectors with harsh, abrasive or corrosive products that would require frequent and expensive maintenance. External mounting has the added benefit of allowing for installation during ongoing production.   

What are common applications for radiation-based level measurement?

Radiometric sensors measure reliably also under extreme process conditions including high pressures and extreme temperatures.

For the toughest applications, radiation-based level measurement is the only solution. VEGA’s ProTrac series of radiometric sensors offers product and performance features that were once considered unattainable under extreme process conditions including high pressures and extreme temperatures. The flexible FiberTrac detector is a popular choice for curved and bullet-shaped vessels, and it is offered in lengths up to 23 feet for continuous level measurement in tall vessels. Highly sensitive SoliTrac instruments are the perfect fit for vessels with thick walls, or in applications where a small source is required.

Discover the possibilities for radiation-based level measurement in your industry