Stringers are represented in red, green, and blue. The corresponding stretch form blocks are shown in gray.
The primary structural components of an airplane fuselage are frames and stringers, which together make up the skeleton of modern commercial aircraft. Frames run perpendicular to the fuselage skin, simultaneously giving the aircraft shape and preventing the skin from buckling under bending loads. Stringers run parallel to the fuselage skin and transfer the aerodynamic loads from the skin to the frames. Stringers provide a significant increase in skin strength with a minimal increase in weight.
In the figure, stringers are represented by number 16 and are colored red, blue, or green.
The stringer (represented in red) is gripped in the arms of the stretch-form (represented in blue) and stretched over the stretch-form block until plastic deformation is achieved.
gLike
Stringer Stretch Form Block
In this project, I modeled stretch-form blocks that were used to create stringers for a new Gulfstream jet.
A stringers is manufactured by stretching an extruded piece of aluminum over a stretch-form block until it achieves plastic deformation and holds the shape of the stretch-form block.
Gulfstream provided the stringer models and material parameters including the extrusion specifications and LMI Aerospace provided the material parameters and relevant dimensions for the stretch-form blocks.
I integrated the parameters from both vendors and created a CAD model that satisfied the requirements for both parties.
This mockup, while representative of the process, contains no proprietary information.
