When ABB acquired Elsag Bailey and Taylor Instruments, along with the acquisition came a set of interesting, unique flow devices, as well as some trusted old friends like magnetic flowmeters and rotameters. Steve Pagano, senior product manager for the venerable Wedge flowmeter and the vortex and swirlmeter product lines, displayed the latest iterations of these unique devices at the 2008 ABB Automation World Exhibition, held this week in Houston.
This Wedgemeter, complete with redundant remote seals for coker applications, was among the tried-and-true flowmeter technologies on display in the 40,000-sq ft exhibit area at the 2008 ABB Automation World.
“We are taking the Wedge places it has never been before,” he said. “We’re using it in the tar sands in Canada. We’ve made it out of special materials, and we’re using it to measure oil-sand slurry. It is working very well, and we are selling more of them every month.”
The Wedge is a unique application of differential pressure flow technology, which uses a wedge-shaped restriction in the flow to produce the differential in pressure that is proportional to the square of the flow rate. This wedge is designed to produce a highly accurate differential even under extreme conditions. Oil-sand slurry certainly falls in that category. The Wedge can be furnished with any ABB differential pressure flow transmitter and can even be fitted with the new high-abrasion-resistant Diaflex diaphragm coating material.
“I worked with the Wedge for many years,” Pagano said, “and then I fell in love with the swirlmeter. We have had 40% growth in the vortex and swirl product lines in the past year, and the split is now 62% in favor of the swirlmeter.”
Swirlmeters, of which ABB is the only current manufacturer, are fluidic flowmeters like the vortex-shedding meter and the Coanda-effect flowmeter. They are the third member of this family of flow technologies—the vortex-precession flowmeter. Once considered a not-very-interesting precursor to the vortex-shedding meter, the swirlmeter came into its own in the past decade when ABB combined the sensor and transmitter designs for both the vortex and swirl products into a single product family. Unlike vortex-shedding flowmeters, swirlmeters require virtually no straight upstream run and very little downstream, making them ideal for steam and chiller water flows. The flow is conditioned by a turbine-like stationary assembly, which imparts a twist to the flow as it enters the meter body. A slight restriction at the outlet causes a standing precession of vortices, the frequency of which is proportional to flow. Because the flow is conditioned at the inlet, swirlmeters can be used directly after a 90-degree elbow or reducer transition fitting.
Swirlmeters cost more than vortex-shedding meters do because of the increased cost of the flow tube. For plain vanilla applications, ABB sells the vortex half of the product. But the swirlmeter earns its keep. “I’ve done a life-cycle cost analysis versus the vortex meter,” Pagano said, “and the swirlmeter costs less to operate over its lifetime.”
Last but not least, ABB’s Blake Doney, vice president for flow and analytical instrumentation, pointed out that ABB is one of the few remaining manufacturers of high-precision glass and metal tube variable-area meters—rotameters. “We continue to see our business in this area increasing, even as the market for rotameters itself gets a little smaller every year,” Doney said. “After flirting with newer technologies, many users are finding out that rotameters are a tried-and-true technology that continues to work without stress for many years. Other methods require power supplies and expensive local indicators, and they cost more than a simple glass-tube rotameter. And if you have a bank of them, you have the ability to ‘line out’ the indicators to get a snapshot of the process. You can’t do that as easily any other way.”