Transportation and Packaging Techniques to Improve Realiability

An outline is presented of probable environments to be expected in shipping electronic equipment by the following: 1. Aircraft transport vehicles 2. Railroad 3. Trucks 4. Ships The environmental engineering data is based upon previous studies and military governing specifications. Orders of magnitude are given as yardsticks for shock design inputs in terms of G level shock pulses, pulse shapes, pulse durations, population of pulses and direction of pulses. Test procedures to simulate environment shocks are described. Accelerated life test philosophy is defined. Similarly, orders of magnitude are given for low frequency vibration inputs as terms of cumulative cycles, frequencies, G levels and amplitude levels. Test procedures are briefly discussed. Discussion is included regarding electronic equipment resistance to environmental transportation shock and vibration. References are cited for the performance of rigorous analyses for determination of natural frequency and transmissibility. Recommendations are made for qualitative evaluation of electronic equipment resistance in shipping environments. Transmissibility across suspension system during shock and vibration excitation is discussed. Incompatibility between shock and vibration isolation is discussed.