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A new high speed forming process for fatigue rated index head rivets used in wing panel assembly using ball-screw based servo squeeze actuation has been developed. The new process is achieved using a combination of force and position control and is capable of forming to 40,000 lbs at rates of up to 200,000 lbs/second whilst holding the part location to within +/− 10 thousandths of an inch. Multi-axis riveting machines often have positioning axes that are also used for fastener upset. It is often the case that while a CNC is used for positioning control, another secondary controller is used to perform the fastener upset. In the new process, it has been possible to combine the control of the upset process with the machine CNC, thus eliminating any separate controllers. The fastener upset force profile is controlled throughout the forming of the rivet by using a closed loop force control system that has a load cell mounted directly behind the stringer side forming tool.

Implementation of a high speed drill motor with solid carbide drill bits, along with careful attention to all details of the process, has resulted in an extraordinary increase in drill bit life, as well as improvements in cycle time and hole quality. During the implementation of a new wing panel riveting machine for use on the 737NG and 757 models a major goal was to significantly improve the drilling process. The phase out of Freon™ as a coolant/lubricant on existing machines forced changes to the drilling process, which resulted in a significant reduction in drill life, from an average of approximately 1,500 holes per drill to 305 holes. The new process on the new machine has increased the average drill life 11,375% to over 35,000 holes, decreased the drill cycle time by 80%, and improved hole quality.