Flow Switch Protects Against Dry Run Conditions

With a no-moving-parts design, Fluid Components International (FCI) says its FLT93 flow switch provides a reliable early warning alert to the potential of dry running conditions, cavitation and other pump issues that can lead to emergency shutdowns, service interruptions, and costly maintenance. The dual-alarm switch monitors the flow and temperature of liquids, gases, slurries, and other media.  It is viable for pump wet/dry detection, where sudden, unexpected reductions in media flow rates can leave pumps vulnerable to over-heating conditions that shutdown process lines. 

 

With Alarm 1, the switch will detect a low flow situation anywhere between 0.01 and 3 feet per second (0.003 to 0.9 meters per second MPS). This low flow alarm can be regarded as a pre-warning signal for the control system or operator. The system or operator can then decide to keep the pump running or to shut it down.

 

If an Alarm 2 occurs because the feed line to the pump is running dry, this condition would be an emergency signal to shut down the pump immediately because the bearings now see gas instead of a liquid as a heat transfer media. In such situations, the temperature of the bearings may rise very fast. Using a flow switch prevents permanent damage to the pump’s bearings that will require an overhaul of the pump before more damage occurs.

 

The FLT93 is a dual-function instrument that indicates both flow and temperature, and/or level sensing in a single device. Dual 6A relay outputs are standard and are assignable to flow, level, or temperature.  It is hydrostatically proof pressure tested to 3500 psig [240 bar (g)] at 70°F (21°C).  De-rated with temperature, the maximum operation service recommended is 2350 psig [162 bar (g)] at 500°F (260°C). Higher ratings are available with special construction and test certification.  Agency approvals include: FM, ATEX, CSA, CRN and CE.

 

Highly dependable, FCI’s versatile FLT93 Switches are ideal for applications in many demanding hazardous process industries.  They also used extensively with or without SIL2 certification in a wide variety of applications in the food/beverage, mining/milling, pulp/paper, pharmaceutical, water/wastewater treatment and more. For more details, an FLT93 demonstration is available, as well as FLT93 datasheets. For further details, visit FCI, call 800-854-1993 or 760-744-6950, and/or email queries to [email protected].