Hill PHOENIX Converts Leak Test Gas from Helium to N2/H2 for Substantial Cost Savings


Hill PHOENIX, a leading manufacturer of refrigeration systems for commercial installations, needed a way to cut gas costs without sacrificing its reputation for quality. The Conyers, Ga.-based company used helium to test for leaks in its units, but gas prices were escalating and supply restrictions drove them even higher. With the cost of helium projected to continue to rise for the foreseeable future, the company knew prices weren't coming down, but teamwork and a willingness to test new options led to a solution that will save the company $300,000 a year.

Hill PHOENIX used helium leak detectors to ensure that all welded joints, mechanical joints and externally supplied components were tight and would not allow any refrigerant gas to escape. Stringent specifications allow a loss of only 0.1 ounces per year to ensure the installed refrigeration system will remain reliable for many years.

Knowing it needed to change its system, the company created a task force led by Senior Procurement Engineer Philip Stephenson to investigate what options were readily available to both reduce the cost and solve the supply issues associated with helium.
The team's initial suggestion was to reduce the amount of helium used, either by reducing the concentration of the gas or by installing helium reclaim units, but Hill PHOENIX found problems with these ideas. Reducing the gas concentration made the detectors less sensitive in finding leaks, creating the chance of reduced product quality. Installing a helium reclaim unit is extremely expensive and because the systems are far from 100 percent efficient, helium would still be required to frequently replenish and purify the system.

The company called upon its existing helium leak detector supplier, Alcatel Vacuum Products,Inc. to help find a solution to reduce short- and long-term costs with no negative impact on leak detection capabilities. The meeting with Alcatel led to an inventive suggestion: using diluted hydrogen as an alternative leak testing gas.

"We obviously had some initial reservations about the use of hydrogen within the plant and the use of new detection technology, but the proposal by Alcatel was very cost attractive and well worth additional scrutiny," Stephenson explains.

The test gas proposed by Alcatel was a mixture of 95 percent nitrogen and 5 percent hydrogen, which, according to ISO 10156, is a safe, non-flammable green-labeled gas. The test gas mixture is readily available and inexpensive-meeting two of Hill PHOENIX's requirements. Having established that the gas was completely safe to use and would save hundreds of thousands of dollars annually, Hill PHOENIX decided to evaluate it further.

"It was important to us not only that the detectors would prove to be reliable and detect the smallest of leaks in production, but also that all of our staff and operators agreed and accepted the change," Stephenson says.

Alcatel's Adixen H2000 ICE leak detector was put through the paces at the plant. It was rotated through all phases of the production process and used by each of the assigned operators.

"The unit performed exceptionally well during the evaluation period and passed all of our tests with flying colors," Stephenson adds.

The next stage was a final cost justification and deciding how the gas would be supplied-mixing the gas on site, which required bulk storage of nitrogen and hydrogen, or having tube trailers supplied with pre-mixed gas.

"For Hill PHOENIX the tube trailer option made the most economic sense," Stephenson explains. "Hill PHOENIX was already using tube trailers with helium so the conversion would be simple and effective."

When the company realized it would save almost $300,000 every year without the added burden of mixing the gas at the plant, it wrote a purchase order to Alcatel Vacuum Products for 15 H2000 ICE leak detectors. Hill PHOENIX has subsequently ordered an additional 7 H2000 leak detectors for its facility in Virginia.

"The new leak detectors have been running at our Conyers facility for a few months now, and our decision to change has been fully justified," Stephenson says.
The Adixen H2000 ICE leak detectors weigh less than 11 pounds, making them easier to move and to bring to harder to access areas than the previous helium units.

"The lightweight portability of the detector has also opened up an opportunity for us to use the detector at the installation site," he explains.

At installation sites such as grocery stores, the refrigeration systems have final assembly joints still to connect to the individual refrigeration cases, which means additional leak testing is needed. Hill PHOENIX purchased four battery versions of the Adixen H2000 ICE detectors and is able to easily test its larger refrigeration systems at the site. Previously, the leak test method on-site was to first vacuum test the refrigeration system for a few hours, and then if no leaks were indicated by a pressure rise, it was pressurized with the refrigerant.

"Pressure testing will not find the leaks we find in the factory and does not indicate the leak point even it does detect a leak," Stephenson adds.

Pressurizing with a refrigerant is expensive and negatively impacts the environment if the gas has to be vented to repair a leak. Pre-testing the completed refrigeration system with N2/H2 and using the H2000 ICE detector finds the significant leaks that the pressure test does not and also pinpoints the leak site. Repairs and rechecking can often be made without venting the gas.

Additional benefits from the switch from helium leak testing to testing with N2/H2 gas mixture include:

o H2000 ICE's solid-state detection technology requires no scheduled maintenance - no probes to clean and no valves and pumps to service.

o H2000 ICE has a very fast response time to a leak and is independent of the probe cable length.

o The test gas mixture, 95 percent/5 percent, dissipates quickly, allowing fast pinpointing and no downtime from background contamination.

o As a diatomic gas, hydrogen does not cloud like helium so large leaks can be pinpointed easily without the need to use messy soap solutions.

"Switching from leak testing with helium to leak testing with diluted hydrogen has been all positive for us," Stephenson says. "We have dramatically reduced our costs, retained our renowned product quality, reduced our time to find large leaks without having to revert to messy soap solution methods, and we anticipate that we will be helping the environment by reducing refrigeration leaks at the installation site."

COMPANY PROFILES

Hill PHOENIX Inc., a Dover Company, is based in Conyers, Ga. The company designs and manufactures commercial refrigerated display cases and specialty display products, refrigeration systems, integrated power distribution systems and walk-in coolers and freezers. Hill PHOENIX is the result of the merger of refrigeration companies whose industry footprint span more than 100 years. The company has a rich tradition of innovation, service, and technological advancement that continues into the 21st Century.

Hill PHOENIX Inc.,1003 Sigman Road, Conyers, GA USA. Tel: 770-285-3100
www.hillphoenix.com

Alcatel Vacuum Products, Inc is an equipment supplier with 900 employees worldwide. Its core business is vacuum technology. Its product offering includes vacuum pumps, vacuum gauges, helium and hydrogen leak detectors, all carrying the Adixen logo as a brand name. The Adixen(TM) H2000 ICE is manufactured by Alcatel Vacuum Products, Inc.

Alcatel Vacuum Products, Inc., 67 Sharp St., Hingham, MA USA. Tel: 781.331.4200, www.adixen-usa.com

For more information, please contact: Dave.Morris@adixen-usa.com

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