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Automated Valve Makes Awesome Waves
August 3, 2007
How Assured Automation helped CA parks engineers overcome design flaws that plagued their new Wave Fountain, which pumps water at the rate of 11,000 gpm.
With
close collaboration between the Long Beach, California’s Parks engineers and
Assured Automation, design flaws that plagued their new Wave Fountain were
overcome to provide a new attraction to the Queen Mary Events Park and
Aquarium, adding dynamic impact to the nationally acclaimed park. With water
being pumped at the rate of 11,000 gallons per minute, it was no less than a
harrowing experience to the Parks engineers when the original fountain design
failed.
“The
water hammering felt like a gunnery range,” recalls Dave Edgar, mechanical
engineer for the City of Long Branch. “Imagine a thousand pounds of metal
objects slamming and pounding all at the same time.”
The original poppet solid on-off valves installed on two
manifolds caused destructive harmonic vibrations in the equipment when they
were opened and closed in different sequences. The poppet valves failed within
days of the installation. Rather than continue with outside consultants, the City
of Long Branch turned to Dave Edgar, their resident mechanical engineer to find
a solution.
Originally trained as a Hull Technician in the Navy, and
then as a marine pipe fitter for the Long Beach Naval Shipyard, Edgar knew from
experience the existing design would never work. Finding
alternatives—especially in an environment where a test prototype was not an
option—needed resourceful and daring minds.
Finding a Solution
The Long Beach Wave Fountain presented rigorous -- literally crushing – requirements. And as a municipal park fountain, the requirements for minimal maintenance and reliable performance were strict.
Edgar scoured publications for solutions, and even called fountain engineers at the Bellagio in Las Vegas, but encountered a wall of proprietary systems. Relying on his knowledge of flow control and working collaboratively with Assured Automation, his valve supplier, Edgar improved the design with three key changes:
* Adding expansion loops in the pipes;
* Adding hydro dampeners; and
* Replacing the poppet valves with by high-speed, durable and reliable pneumatic Ares Angle Seat Valves with fast acting solenoids engineered by Assured Automation in Clark NJ to control the 150 water jets.
The expansion loops reduce the harmonics. The hydro dampeners keep the seat from slamming close, softening the impact. The Ares Angle Seat Valves were selected for their high cycle-life, durability and reliability, and compact assembly.
“Finding the right valve for our Wave Fountain was key to the success of the project,” recalls Edgar. “Other more common valves could not meet our stringent requirements. We worked collaboratively with the engineers at Assured Automation to find the right solution to meet our specs. And the effort has paid back.”
High Cycle-Life
The ideal internal flow characteristics, with its maximum capacity and high duty cycle, provide better performance compared to other valve designs. The Angle Seat Valve’s piston is unique, enabling the plug to retract farther from the flow path, ensuring the highest flow capacity. The dual packing design, and a large-diameter, self-aligning stem, insures the highest cycle life.
Durability and Reliability
The Wave Fountain is designed in the shape of a chambered nautilus.
The special internal conformation of the valve seat avoids excessive deformation of the PTFE seal at high temperature or pressure, making the Ares or Zeus a long-lasting valve. The self-aligning plug design guarantees a high duty cycle under all kinds of pressure. The valves work well in a wide temperature range, from -14°F to 358°F, making them a good choice for outdoor plaza fountains.
The Stainless Steel Spring, and the particular shape of the dual self-adjusting stem seals, ensure a perfect tightness through wear and tear of time. The metal piston coated with a slow-wearing protection, and the employment of self-lubricating guides and seals guarantee an almost unlimited life to the pneumatic control section—even through constant use under the most extreme conditions. The valve is provided with long-lasting seals.
Compact Assembly
The control head rotates 360 degrees for selective positioning of the pneumatic inlet port. Available in sizes from 3/8” to 2”, the pneumatic valve is small, but with a series of 135 jets, packs a big wave.
Quality Solution
Visitors to the park’s Wave Fountain are awed by its power and well-choreographed tidal surges. Architectural fountain designers are awed by its simplicity and endurance. The waves are generated by computers, which control the solenoids, and, in turn, drive the valves in an air-tight system. The valves cycle nine times per minute. Each hour, two 15-minute shows are run, for ten hours a day.
With 1.5 million cycles in more than a year and a half, not one valve has failed. Paul Bays, maintenance/operations supervisor of Queensway Bay Parks, Recreation & Marine for the City of Long Beach, reports, “The Ares Angle Seat Valves have performed exceptionally well, meeting the fountain’s demanding requirements.”
The Wave Fountain measures up to the city’s mission to “create community and enhance the quality of life through people, places, programs and partnerships."
Assured Automation is a privately held company that sells automated valves, actuators, flow meters and valve accessories. For more information, visit www.assuredautomation.com.
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