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This paper gives an outline of testing carried out in conjunction with Electroimpact to support the introduction of the A319/A320/A321 and A340-500/600 Panel Assembly Cells in Broughton, UK. Testing compared the percussion insert/EMR swaging of lockbolts with existing hydraulic installation methods. Tests included pre-load tension tests, ultimate tension load tests, tension fatigue tests, high-load lap shear fatigue tests, static lap shear tests, a pressure leak test, and metallurgical examination. Fastener configurations tested covered diameters from 1/4, 5/16, 3/8, and 7/16 of an inch. Joint materials conformed to ABM3-1031 (7150-T651 plate), stump-type lockbolts to ABS0550VHK (Huck LGPS4SCV), and collars to ASNA2025 (Huck 3SLC-C). Some pull-type lockbolts to ABS0548VHK (Huck LGPL4SCV) were also tested as noted.

Robotic gripper technology has been integrated into CNC riveting machines. Handling fasteners efficiently is critical in automated wing panel riveting. Computer controlled rivet gripper and collar gripper technology has been developed that demonstrates high reliability and decreased fastener cycle times

British Aerospace needed an automated wing riveting system for fastening the A320 wing sections. The E4000 Wing Riveting System was designed and installed at their Airbus factory in Chester, UK and is now in production. It uses a five axis solid yoke with workheads on each end of the yoke. It accurately installs both rivets and lockbolts over the entire wing panel, including offset areas.

Boeing needed a process to replace hand drilling for floor panel holes and galley and lavatory mounting locator holes in the floor grid of the completed 737 fuselage. Electroimpact developed a process, and the 737 AFDE machine, that is a substantial improvement over existing technology. It provides full CNC control, quick reconfiguration of hole patterns, fast drilling of up to 3000 holes in one 8-hour shift, drills both titanium and aluminum and works inside the fuselage.

A new wing panel riveting cell capable of replacing tack fasteners and performing small repair jobs has been developed. Using two mobile scissor lift platforms with electromagnetic riveters mounted on each, the operators can access every portion of the wing panel without the use of ladders or platforms. This method minimizes fatigue, allows workers to carry all tools and supplies with them, meets current safety standards and minimizes coldworking of the components.

McDonnell Douglas Aircraft in St. Louis, MO manufacturers various transport and fighter military aircraft such as the C-17 and the F/A-18. With shrinking military budgets and increased competition, market forces demand high quality parts at lower cost and shorter lead times. Currently, a large number of different fastener types which include both solid rivets and interference bolts are used to fasten these assemblies. The majority of these fasteners are installed by hand or by using manually operated C-Frame riveters. MDA engineers recognized that in order to reach their goals they would be required to rethink all phases of the assembly system, which includes fastener selection, part fixturing and fastener installation methods. Phase 1 of this program is to identify and to develop fastener installation processes which will provide the required flexibility. The EMR fastening process provides this flexibility.

Northrop Corporation manufactures body panels for the Boeing 747 aircraft. There are 1259 different stringer configurations used on the three 747 models with an average of 839 stringers per ship set. Until recently, all drain holes and skin coordination pilot holes were drilled manually using plastic application template tools (PATTS). Inventory costs were high and manual drilling errors led to excessive scrap and rework rates. Northrop engineers recognized that automating the stringer drilling process would produce higher quality parts at a lower cost. Northrop worked with Electroimpact, Inc. to develop the Automatic Stringer Drilling System (ASDS). The ASDS automatically clamps and drills all straight and contoured stringers used on the 747. Stringers are mounted on a rotating platform that provides +/- 90° of motion. Two servo-servo drills are mounted on a cantilevered arm with 25 feet of X-axis travel.

Hand installation of 3/8", 5/16" and 1/4" diameter fatigue head style fasteners is required on some areas of 747 section 11 (center wing). The 3/8" diameter fasteners can require between 45-60 seconds to upset using conventional pneumatic riveting guns. As part of Boeing’s continuing effort to reduce cycle time and improve the factory working environment, a Boeing Quality Circle Team proposed using LVER technology as an alternative to conventional pneumatic percussion riveting hammers The hand operated HH500 system was developed in response to this request. The HH500 single shot upset reduces installation time as well as the noise levels and vibration experienced by the operators. The design of this system and the integration onto the factory floor are presented. The LVER forming rate is significantly higher than that of conventional pneumatic and hydraulic processes.

British Aerospace, Airbus Ltd., Chester, UK manufactures the main wing box assembly for all current Airbus programs. Titanium interference fasteners are used in large numbers throughout these aircraft structures. On the lower wing skin of the A320 alone there are approximately 11,000 of this fastener type. Currently, the majority of these fasteners are manually installed using pneumatic or hydraulic tooling. British Aerospace engineers recognized the significant potential which automation offers to reduce these current labor intensive installation methods. Electroimpact proposed extending Low Voltage Electromagnetic Riveter (LVER) technology to the automatic installation of these interference fasteners as well as rivets. Close liaison between Airbus and Electroimpact engineers resulted in the development of an automated LVER based lockbolt installation system, which is currently undergoing evaluation.

Two Automated Electromagnetic Riveting Assembly Cells (AERAC) were manufactured for Textron Aerostructures by Electroimpact, Inc. The AERAC installs the final rivets in the A330/A340 upper wing panel in the floor assembly jig. At Textron for each wing the corresponding floor assembly jigs for each wing are lined up end to end. An operating procedure in which the formboards are removed in bays allows efficient operation of an in the jig riveter such as the AERAC. Specialized machine codes developed for the AERAC allows quick fully programmed stringer to stringer jumps of the stringer side offset tooling. The AERAC is programmed entirely from a CATIA drawing of the part. Of the 5 axes of rivet data available only two are retained for use by the AERAC.