Car makers and their suppliers are facing newpassive-restraint safety requirements coupled with an ongoing need to reducecosts and improve the quality of component testing.
In the U.S., 50 percent of all vehicles under a grossvehicle weight of 10,000 pounds built after Sept. 14 will be required to meetnew side-impact requirements (FMVSS 226); 75 percent by 2015, and 100 percentby 2016.
Most manufacturers are expected to modify currentside-impact airbag curtains to meet the new standards. Elsewhere around the world a number of otherpassive restraint rules also are taking effect. In Brazil and Argentina, forexample, front airbag systems now are being required for all passenger cars andother light vehicles.
Frontal airbags have proven to reduce fatalities infrontal crashes by up to 25 percent and reduce serious head injuries by morethan 60 percent, according to Thomas Parker, sales manager for INFICONAutomotive in North America. Globally, more than 300 million airbag systems areproduced annually and the number is expected to grow on an annual basis byeight percent through 2016.
The average car buyer doesn’t realize that most new carsare equipped with as many as 12 airbags, Parker points out. A variety of different airbag systems arecurrently in production or under development, including:
— Side curtain airbags decreaselife-threatening head injuries in side
impacts byapproximately 50 percent.
— Dual-chamber side airbags further protectchest and pelvic areas,
reducingserious injuries by 25 percent or more.
— Knee airbags significantly reduce hip, thighand knee injuries which
representnearly 25 percent of active-life years lost as a result of
— Anti-slide airbags raise the front portion ofa seat cushion to prevent
theoccupant from sliding under the seatbelt, significantly reducing
knee, hipand thigh injuries for belted passengers.
— Bag-in-belt systems, combinations of seatbeltand airbag, reduce the
load on anoccupant’s ribcage in front collisions.
— Far-side airbags inflate between seats andprevent the sideways movement
ofoccupants. Research shows that 30 percent of all serious injuries in
side-impactcollisions result from a far-side passenger hitting another
occupant orhard object.
Three basic types of automotive airbag inflation systemscurrently are available, including:
— Pyrotechnic inflators that use the combustionof propellant to create
gases toinflate the airbag;
— Compressed gas products that storehigh-pressure inert gas (sometimes
helium orargon) for release in milliseconds, and
— Hybrid pyrotechnic and stored-gas systemsthat use a combination of both
forflexibility and performance.
“Leakage standards for airbag inflators are amongthe tightest in the auto industry – much tougher than requirements set forfuel, air conditioning or brake systems,” Parker says.
All inflators, regardless of type, are leak tested withhelium leak-detection equipment to ensure that the inflator will perform asexpected during the life of the product. The loss of stored gas in the inflatorcould seriously affect airbag performance during an accident. If a pyrotechnic inflator has a leak, watervapor can enter the inflator, react with combustible material in the system andcause the airbag to deploy unexpectedly.
The INFICON executive adds that every type of inflatoralso uses a small pyrotechnic device called an igniter, which is helium leaktested as well. He estimates thatautomakers and their suppliers annually conduct more than 600 million leaktests on airbag inflator components and igniter-based seatbelt pretensionsystems in the United States alone.
“There is an ever-increasing demand for quick,low-cost and highly reliable leak-detection equipment, especially when it comesto airbag inflators and igniters,” says Parker. “Manufacturers who have introducedautomated INFICON test systems have achieved a 100 percent return on theirinvestment within three-to-six-months based on savings from lower maintenancecosts and increased productivity.”
Paul Chamberlain, president of LACO Technologies, aglobal supplier of helium leak-detection systems for testing inflators andigniters, states: “LACO has manufactured many leak test workstations inwhich the inflator can be loaded in the test chamber by either an operator orrobotically. These systems can yield part-to-part test cycle rates of less than10 seconds per part.”
Reliability and high throughput are key airbag inflatortest requirements. Parker notes that one major airbag supplier reduced cycletimes for compressed gas inflator testing by 43 percent, from 19 seconds to 10seconds per test, adding that INFICON systems can go without adjustment or recalibration for 24,000 hours ofoperation or more.
“INFICON product names aren’t familiar to new-carbuyers, but they’re well-known to quality-control managers throughout the autoindustry,” Parker says. “Our products help assure the quality ofliterally millions of new cars and trucks.”
Vacuum Technology Inc. (VTI) in Oak Ridge, Tennessee is adiversified provider of leak detection systems for the automotive industry.VTI’s President George Solomon adds that his company recently developed aninflator leak test system based on an INFICON gas analyzer for testing withargon gas instead of helium for hybrid inflator applications.
Other major automotive components and systems thatrequire leak testing include:
— Fuel Systems – Fuel tanks; filler caps andnecks; fuel injectors; fuel
pumps; fuellines, and filters.
— Driveline Components – Engine oil circuits;transmissions; torque
converters;intercoolers; electric car batteries; natural gas engines,
andhydrogen and natural gas fuel tanks.
— Oil and Water Systems – Plastic oil tanks;oil pans; oil coolers; oil
pumps; coolant expansion tanks; watercoolers, and water pumps.
— Safety Components – Brake fluid reservoirs;power brake boosters; vacuum
brakepumps; brake hoses; seat belt pretensioners; airbag igniter caps,
— Air Conditioning Systems – AC hoses;compressors; evaporators;
condensers,and filling valves.
— Other Systems – Power steering housings;servo oil reservoirs;
windshieldwiper-fluid containers; wheels; shock absorbers and starter
INFICON is one of the world’s leading developers,producers and suppliers of instruments and devices for leak detection in airconditioning, refrigeration and automotive manufacturing. The company hasmanufacturing facilities in Europe, China and the United States, as well assales and service offices throughout the world.
More information about INFICON automotive technology isavailable online at www.inficonautomotive.com.