Inherent Viscosity Testing
Inherent Viscosity testing of polyimide (Kapton®) wire insulation supporting Service Life Extension Programs (SLEPs)
Polymers degrade over time. Degradation in internal integrity could lead to mechanical failures and, in operation critical environments, serious accidents. Measuring the inherent viscosity, or the molecular weight of polymers, is a thoroughly proven and effective technique to assess the polymers’ internal integrity.
Through an exclusive agreement with DuPont, Lectromec now brings the inherent viscosity test (IVT) to the aviation community. For all wires insulated by DuPont’s Kapton® film, the IVT can offer superior insight into their current condition and provide valuable guidance in the monitoring and maintenance of aircraft wiring systems.
Damaged or degraded wiring systems have led to aircraft accidents and will continue to pose a formidable threat. Fortunately, many such accidents can be easily avoided with an improved understanding of the systems’ current condition. Lectromec has an excellent suite of laboratory analysis tools that can provide wiring engineers a clear “360-degree” understanding of wiring systems. IVT makes it possible to get an even more in-depth view into polyimide, e.g., Kapton®-insulated wires.
For each wire insulation tested, the insulation’s present molecular weight is plotted against DuPont’s minimum molecular weight measure. This is an important comparison that can result in valuable guidance for the scheduling of maintenance activities, rewiring actions, and periodic monitoring. Additionally, it provides insight into the recommended minimum bend radius for the wire when deployed in particular zones. These findings can be further leveraged and detailed by combining IVT with WIDAS testing and EWIS risk assessment.