Saelig Company, Inc. has introduced the Portatank® Tank Level Indicator, which can detect liquid levels non-invasively through the outer walls of a storage tank without any permanent installation. It can measure liquid levels inside storage tanks with diameters of 1.5’ to 50’ and wall thickness of 0.004” – 0.8”, which are made of most common materials such as steel, plastic, and aluminum. Unlike traditional methods of level testing, the Portatank uses ultrasonics to provide non-invasive level measurement.
Coltraco Portatank® Handheld Ultrasonic Tank Liquid Level Indicator (3141184-TANK). Image Credit: Saelig Company, Inc.
The Portatank measures levels of all kinds of fluids, particularly hazardous liquids where the tank cannot be opened for safety reasons or where a float gauge cannot be installed. With this external, non-invasive, non-intrusive technology, the Portatank is suitable for testing hazardous liquids without the risk of contaminating the liquid. As the liquid storage system is undisturbed during testing, and no removal of lids needed, risks to the person conducting the test are also minimized. Operating the Portatank simply involves simply placing the ultrasonic sensor on the container wall to find a quick liquid/no liquid location. The Portatank is accurate to +/- 10mm, and it provides a safe, quick and accurate method to monitor contents. This adaptable technology works with liquid levels that fluctuate over time, as well as being able to test a wide range of tanks and liquids. For tanks that already have a built-in level-sensing system, such as float level or sight-glass, the Portatank® allows operators to compare and verify liquid levels in tanks with existing indicators.
The Portatank’s detection method uses high-frequency ultrasound transmitters that emit ultrasonics waves at frequencies of 200 kHz up to 2 MHz. The propagation and attenuation of sound waves is affected by the structure of the medium down to an atomic level, making ultrasound a useful method for studying a material’s structure and the processes occurring within it. The ultrasound is conducted through the solid walls of the tank, which then interacts with the contents. After the sensor stops emitting ultrasound, it starts listening for the returning echoes of the signal. If liquid is present, the echoes will return to the instrument and the instrument will react accordingly through LED indication. If no liquid is present, the echoes will not be returned. This process allows the instrument to detect the presence or absence of liquid behind the area of the container wall where the sensor is placed. This method of ultrasound liquid level detection is commonly known as “pulse-echo”.
The Portatank allows one instrument to be used across multiple tanks on the same site and requires only a single operator and no installation costs. The Portatank is also a suitable “interim” instrument for detecting liquid level in tanks undergoing maintenance or re-fitting of their built-in level gauges. Typical applications include food and drink processing, pharmaceuticals, oil & gas, chemicals, petrochemicals, water treatment, fire safety, breweries, wineries, process industries, transformers and ring main units (oil levels). Power transformers can remain “live” during non-invasive Portatank testing without opening them. When a transformer is opened, there is a risk of introducing oxygen into the structure. If the oil levels are depleted, there is a potential for combustion to occur with the mixing of oxygen due to the excessive amount of heat generated by the transformers themselves in the absence of oil which cools and insulates the structure.
The Portatank Tank Level Indicator is made in UK by ultrasonics specialists Coltraco Ultrasonics, global leaders in the monitoring of systems that protect high-asset value and critical national infrastructure installations. It is supplied in a handy, robust carrying case. It is available now from now from Saelig Company, Inc. Fairport NY their authorized USA technical distributor. For detailed specifications, free technical assistance, or additional information, please contact Saelig 1-888-7SAELIG.