Reduction in Variability in Liquid Locking Compound Applications.

Liquid locking compounds (LLCs) are often applied to fasteners in missile applications to augment preload in resistance to vibration-induced loosening. The amount of LLC needed to reach a specified locking torque varies greatly depending on the fastening system. There is a need to apply LLCs to fastening systems consistently and with known adhesion characteristics to provide OEMs with a repeatable process that can be used in manufacturing. Systems & Materials Research Corporation (SMRC) proposes to utilize their expertise in fastening systems, materials science, and Lean Six Sigma to tackle this issue. Cure and adhesion characteristics will be evaluated for each fastening system and LLC type, then fed into a design of experiments for evaluation against LLC locking torque requirements. A new LLC application process will be developed and validated on relevant fastening systems with the goal of identifying root causes and eliminating variation. Application tooling will be assessed to aid with variation reduction. Approved for Public Release | 16-MDA-8917 (15 November 16)