Vortex Flow Measurement in Severe Service Applications

Emerson's Kei CheungI had a chance to catch up with Emerson’s Kei Cheung at the recent Emerson Exchange conference. She showed me a demonstration of a Rosemount 8800 Severe Service Vortex Sensor.

This technology recently won Flow Control magazine’s Flow Control Innovation Award. About the technology, the editors wrote:

…uses premium nickel alloy material. The non-wetted severe service sensor is only exposed to the ambient environment. With the new piezo crystal design, the severe service sensor provides stable performance at high temperatures up to 850 F, far superior than the competitor 750 F offerings. Designed with the customer’s needs in mind, the Rosemount 8800 Vortex flowmeter system with the new severe service sensor is ideal for harsh environments in chemical, power and refining industries.

Rosemount 8800 CriticalProcess Vortex Flowmeter

I asked Kei about two severe-service applications for this vortex flowmeter, solar power and high-temperature hydrocarbon processes.

For the solar power application, concentrating solar power plants use long parabolic mirror troughs, which focus the sun’s energy on a pipe. The pipe contains oil that transfers this energy to a heat exchanger used to create steam and ultimately, electricity. Temperatures may climb to 600-700degF (315-370degC).

The vortex flowmeter can measure flow rates in the oil at these high temperatures since the weld-end meter body design eliminates leak points from the flowmeter installation from earlier gasket-based vortex meter technology.

For offshore oil and gas production applications, the sea salt laden air can cause sensor corrosion. Kei shared one instance on a water flow measurement on a first-stage production separator. A vortex sensor had failed due to chloride-induced stress corrosion, which cracked a sensor lead wire. This sensor was also located near a high temperature pipe, which accelerated the corrosion process.

The Severe Service Sensor includes a Monel 400 sensor lead wire and Inconel 600 sensor housing material. These materials resist chloride-induced stress corrosion cracking found in near-shore and offshore marine environments.

One of the cool things Kei showed me was an animation of how vortex technology works. From this animation, you’ll see how the vortices are created and picked up by the sensor. The frequency at which these vortices alternate sides is proportional to the flow rate of the fluid.

What other applications do you have in your process where severe-service flow measurements are required?