Scroll down or click here for a closeup look at the actual Alcoa fasteners used on Boeing's 787 Dreamliner!
Inadequate supplies of highly engineered fasteners, ranging from tiny to very large, is one of two chief reasons Boeing is pushing back the first flight of the
toward the end of the year. The other is the need for more software code for the flight control system.
The story behind the shortage is the booming demand for aircraft. Assembly of the and the new super-jumbo A380 from Airbus has spiked demand for the specialized products some 20 percent. The surge comes on the heels of a production cutback when aircraft orders plunged after the Sept. 11, 2001 attacks, which prompted Alcoa to cut about 40 percent of its fastener workforce.
Alcoa supplies more than one million fasteners. Several different types and sizes of fasteners are used for the and A380.
“It’s already tight. With the new programs coming online and production rate increases on other models, it’s going to continue to get worse,” Alcoa Vice President Bill Christopher told Bloomberg News in May.
A Boeing source said the aircraft maker knew months ago it would have to use “temporary fasteners” in the first due the shortage from increased aircraft demand. One area where the shortage is most acute is in the center wing box, GM and Boeing VP said yesterday. However, Boeing declined to give more details on specific fasteners that are in short supply.
Alcoa’s aircraft fasteners include high-temperature, high-strength fasteners for both airframe and engine applications as well as very complex latches. One characteristic is very tight tolerances. “A titanium 3/16-inch diameter fastener would support the weight of an average family car such as a Toyota Camry,” Olivier Jarrault of Alcoa Fastening Systems (AFS) was quoted as saying on an Alcoa web page. “Increase the size to one inch in diameter and the single fastener could support the weight of 50 or more Toyota Camrys.”
One type of fastener that could be used in the 787 is Alcoa’s Huck Asp (Adjustable sustained preload) lock fastening system commonly used in aircraft. A pdf on the Asp fasteners says: “The Asp fastening system has a record of proven performance on most military and civilian aircraft. Some examples are the Boeing family of jet transports, Airbus, F-111, F-14, F-16, F-18, C-
17 and others.”
The Asp line can also fasten metals and composite materials, which are heavily used in the . “The Asp fastening system provides a simplified method of fastening composite, soft core, metallic or other materials which are sensitive to fastener clamp-up or installation force conditions,” according to an Alcoa web page. The Huck Asp systems were developed by Cordant Technologies, which Alcoa acquired in 2000.
Additional capacity was dedicated to the Dreamliner program at Alcoa’s plants in California, but it wasn’t enough. Boeing said Wednesday the fastener shortage, coupled with other problems, is pushing back the first flight of the Dreamliner to November or December. The big show airplane rolled out July 8 was held together with temporary fasteners and about 700 remain to be replaced with permanent ones.
Alcoa has been hiring back workers at its plants in the Los Angeles basin in California, and is also ramping up capacity in Acuna, Mexico and Nemesvamos, Hungary. A new fastener plant in China is expected to open next year.
One example of a complex fitting from AFS is the RFKA9900-13 (SAE AS5550) flareless plug-in union Ring Locked fitting, which was qualified late last year. It’s a high-pressure titanium hydraulic adapter that was selected by Boeing because of its light weight and dual seal protection. It provides up to 49 percent weight savings over the previous design for this application, according to the Alcoa press release. Each uses more than 120 of these parts.
“This fitting is designed with a 20º metal-to-metal seal, which is the primary seal between the fitting and mating port, and also incorporates an elastomeric o-ring that acts as a secondary or back-up seal,” Product Management Manager for North America Doug Pyle said in the AFS press release.
Headquartered in Torrance, CA, AFS had 6,000 employees at the end of last year and manufactures at 26 locations in seven countries.
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