In the demanding world of aerospace, where precision and reliability are key, the method of mechanical joining stands out as an essential technique. Unlike traditional heat-based joining processes such as welding or brazing, mechanical joining in aircraft systems involves the plastic deformation—specifically, the expansion—of a tube end into a fitting or sleeve. This innovative approach creates a robust, leak-proof joint without the need for elevated temperatures, offering a multitude of benefits crucial to the stringent requirements of aircraft design and operation.