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In an effort to simplify and speed up manufacturing time for aircraft structure, a pure mechanical system has been developed by Fatigue Technology Inc. (FTI) to perform the Split Sleeve Cold Expansion (SsCx™) process to fastener holes. Historically, fastener holes requiring cold working for fatigue life enhancement are cold worked with a system which requires a manual hydraulic puller. This system works well and has been in place for more than 30 years. This paper will discuss a new type of system that uses a simplified mechanical-only process that does not require hydraulic pneumatic or electrical systems. This new type of Automated Cold Expansion™ (AtCx™) puller unit has recently been fitted to an automated work cell that machines aircraft sub-components. This new cold expansion puller utilizes only simple rotary motion and converts it to a linear motion. The puller can be fitted to any kind of automated work cell, NC machine, or drilling and riveting equipment.

Fastened joints are an integral part of aircraft design. Due to their complexity and function, they are also the primary source of structural fatigue problems. The incorporation of residual compressive stresses around a fastener hole greatly enhances the fatigue resistance and integrity of a fastened joint. This paper describes the split-sleeve cold expansion method to create residual compressive stresses which extend the fatigue life of holes in both new structure and field repairs. Data from test programs highlight process benefits and crack retardation effects for various specimen configurations. Other process features such as cold expansion to size are explained, along with the status of process automation.

Reduced manufacturing costs and flow time, along with increased structural fatigue life and reduced in-service maintenance problems can be realized with the Fatigue Technology Inc. (FTI) ForceMate® (FmCx™) system of installing high-interference bushings into aircraft structures. Bell Helicopter reported [1] a projected $24 million cost savings with the use of ForceMate. This paper will describe the ForceMate system in detail as well as an alternative bushing installation method, BushLoc, and the manufacturing benefits realized with their use. The ForceMate bushing installation system installs bushings with a consistently high level of interference in a fraction of the time of traditional methods, such as shrink and press fit. It is a safer method, reduces hardware variability and provides a higher integrity bushing installation with significant structural fatigue life improvement.

Typical aerospace hardware and fittings; especially those that penetrate bulkheads, are usually large and heavily flanged, requiring a thick or large diameter pad-up around the penetration hole. The assembly is often complex with multiple holes to accept satellite fasteners to attach the fitting to the structure. This process adds weight to the structure, limits design flexibility, is labor intensive and often time consuming to install. This paper introduces an innovative method of installing aerospace fittings and hardware using proven cold expansion technology. This advanced bulkhead fitting system provides a fast and robust installation process that reduces both cost and assembly complexity compared to traditional methods, while providing a lighter weight installation, increased structural design options and improved fatigue life.