The simplest method of measuring liquid level is through direct observation, but this doesn’t happen in industrial areas, where containers are huge and sealed and cannot be opened without proper resource and safety precautions. Hence a liquid level indicator is used to measure and monitor the liquid level for proper and smooth functioning of all industrial processes. An ultrasonic level indicator is the most advanced and easy method for monitoring levels of liquid in various industrial sectors and plants, as well in household applications. It is considered highly functional and health friendly for measuring liquid content in specific areas:check over here
Applications and Usage
For the measurement of corrosive chemical liquids in chemical plants that cannot be opened directly for safety reasons. For detecting the presence of fluids in standing pipes, particularly to investigate pipes that are being opened for maintenance reasons. For the measurement of fluid levels in automotive components, such as fuel tanks, transmission assemblies and engine oil pans. An ultrasonic level indicator is considered best to measure the layers of different liquid fluids on top of a second liquid. For example, in Petroleum processing system, this liquid level indicator is used to measure the layer of oil over the layer of water. It is used in different fire extinguishing cylinders and sprinkler systems to measure the content of cooling agents.
Unsuitable Factors for Ultrasonic Level Indicator
The performance of an ultrasonic level indicator can be affected by different factors like: If the surface of the container wall is pitied and corroded, it may distort the transmission of the sound pulse back to the transducer, bringing changes in measurement. Curvature of container also plays an essential role in getting the correct measurements of liquid level. If it sharply curved, it may distort sound pulses or cause poor coupling of the transducer to the container. As ultrasonic sound waves travel in straight line, it is essential to clear the sound path of waves of any obstructions such as baffles or fill pipes, to prevent false return of the sound waves.
Acoustic properties of the liquid may also cause change in ultrasonic measurements. Generally liquid of high viscosity or movement of liquid inside the container may also change the viscosity of liquid, thus causing variations in measurement. A constant is essential to getting the right liquid level measurement. Any change in temperature may change the sound velocity of liquid, and may not give the correct readings on ultrasonic level indicator. Other factors like foam, gas bubbles, steam and surface turbulence also causes change in the measurements. Gas bubble inside the container will scatter sound waves and give false readings; steam and turbulence may absorb the sound waves and give incorrect readings.
How to overcome these factors?
The best location to mount an ultrasonic liquid level indicator is usually at the top middle of container, where the sound waves may travel directly in straight line to the liquid surface. Install an ultrasonic level indicator in a stand pipe to prevent changes in temperature, and to keep ultrasonic sound waves away from any foam, steam, gas bubbles or other obstructions. For a slopped or dome shaped tank, use a plastic self-aligning bulk heading to let the sensor keep moving in accordance with the liquid surface.