Limitations of Coriolis mass flow instruments

Limitations of Coriolis mass flow instruments

Coriolis mass flow meters and controllers offer many benefits over other mass flow technologies, but there are a couple key challenges to understand and consider before purchasing a Coriolis instrument.

Multi-phase incompatibility

A limitation of many available Coriolis mass flow instruments, including Alicat’s CODA-Series, is that they are only able to accurately measure single-phase flow. While multi-phase fluids will not damage the instruments, they may significantly lower measurement accuracy.

This does limit Coriolis use in some applications, but the instruments are otherwise quite versatile. CODA meters and controllers are highly resistant to corrosive fluids and have less wetted material than other instruments. They also come with the option to have an IP67 rating, all-metal seals for meters, and operating pressures up to 4000 PSIA for both meters and controllers. View the specs for a complete list of details.

Sensitivity to external vibrations

Coriolis mass flow instruments take measurements using sensors that detect miniscule vibrational changes in the instrument tube(s) as fluid flows through. A major challenge is that these readings can also be sensitive to external vibrations from nearby disruptions. For example, a generator switching on nearby may introduce consistent noise into the measurement; a box suddenly dropping on a test bench may cause a spike in the readings, which could take several seconds to recover from.

CODA’s unique solution

CODA Coriolis mass flow controllerMany Coriolis mass flow meters are sold with a mounting block to decrease sensitivity to external disturbances. These blocks can be a bit bulky, taking up more space and making it trickier to install. Alicat’s CODA-Series Coriolis instruments are specifically designed to be highly insensitive to external bumps and vibrations without requiring a mounting block (check out the demonstration video).

If the device is affected by any sharp sudden interferences like a physical bump, the measurement re-stabilizes in less than 400ms. A few key design elements make this possible:

  • Vibrational frequency: The internal resonance frequency of CODA units is up to 3x higher than competitor units, rendering the instrument less sensitive to lower frequency vibrations.
  • Complementary optical sensing: A series of optical sensors provide additional feedback and mitigate interference when an external vibration is present.
  • Unique algorithm: A proprietary algorithm further combats external interference by identifying and eliminating undesired frequency peaks.
  • Accurate sensors: CODA utilizes the most current sensor technology available.

Expensive compared to other technologies

Coriolis mass flow instruments tend to cost more than twice as much as other mass flow technologies, which is really no surprise as their unique capabilities offer unrivaled versatility. However, Alicat’s CODA-Series of Coriolis mass flow meters and controllers include several different models at varying price points. For applications where high accuracy and resistance to external vibrations are negotiable, a lower cost option may work out perfectly for you.