Mar 14, 2007

Valve Catches the Right Wave

Close collaboration between park engineers at the Queen Mary Events Park & Aquarium in Long Beach, Calif. and valve manufacturer Assured Automation helped ensure that design flaws that previously plagued the park’s new Wave Fountain were fixed.

With water being pumped at the rate of 11,000 gallons per minute (gpm), it was no less than a harrowing experience to the park’s engineers when the original fountain design failed.
“The water hammering felt like a gunnery range,” recalled Dave Edgar, mechanical engineer for the city of Long Beach. “Imagine 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, Long Beach turned to Dave Edgar, its resident mechanical engineer, to find a solution.
Originally trained as a hull technician in the U.S. Navy, and then as a marine pipe fitter for the Long Beach Naval Shipyard, Edgar knew from experience that the existing design would never work. Finding alternatives, especially in an environment where a test prototype was not an option, required resourceful and daring minds.

Finding a solution

The Long Beach Wave Fountain presented rigorous and literally crushing requirements. As a municipal park fountain, the requirements for minimal maintenance and reliable performance were strict.
Edgar scoured industry publications for solutions and even called fountain engineers at the Bellagio Hotel & Casino in Las Vegas, Nev., but encountered a wall of proprietary systems. Relying on his knowledge of flow control and working collaboratively with Assured Automation, Edgar improved the design with three key changes:

  • Adding expansion loops in the pipes;
  • Adding hydro dampeners; and
  • Replacing the poppet valves with high-speed, durable and reliable pneumatic Ares Angle Seat Valves with fast-acting solenoids to control the 150 water jets.

The expansion loops reduce the harmonics. The hydro dampeners keep the seat from slamming shut, softening the impact. The valves were selected for their high cycle life, durability, reliability and compact assembly.
“Finding the right valve for our Wave Fountain was key to the success of the project,” recalled 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 their 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 ensures the highest cycle life.
These 2/2-way pneumatically-actuated piston valves were originally designed for liquids, gases, steam and aggressive fluids applications. The valve body and internal components are made entirely of AISI 316 (Ares Series) and the seals are in PTFE, therefore enabling a high chemical compatibility with almost all media used in the different production processes. The valve is also available in Brass & 316 S/S (Zeus Series).
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 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. 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. Guides and seals are made with a self-lubricating material.
The control head rotates 360° for selective positioning of the pneumatic inlet port. Available in sizes from 3⁄8 in. to 2 in., 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 that control the solenoids, and in turn drive the valves in an airtight system. The valves cycle nine times per minute.
Two 15-minute shows are run every hour for ten hours a day. With 1.5 million cycles in over a year and a half, not one valve has failed.
Paul Bays, maintenance/operations supervisor of Queensway Bay Parks, Recreation & Marine for Long Beach, said, “With over a year and a half of usage 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.”

About the author

Bill Farrell is president of Assured Automation. He can be reached at 800/899-0553 or by e-mail at [email protected].

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