| This project focused on analysis and testing of the separation feature of a free-running threaded locking fastener for use in structural aerospace assembly. Two sizes of fasteners were machined using a Computer Numerically Controlled (CNC) machining process. Installation testing of these fasteners was conducted under various installation conditions, chosen to simulate actual expected usage of the parts in aerospace structural assembly. Results of the study indicate that external factors such as the material and finish of mating bolts and bearing surfaces in the expected usage range for this product play a significant role in the initial separation torque, and therefore influence the success or failure of the installation. Based on the range of preloads developed under various installation conditions, and on the distribution of separation loads from the sample parts, a targeted separation load was chosen to ensure proper installation of the product in a wide range of actual use conditions. |
