Quick look:
- Tests vibration a unit might experience
- Includes four procedures for different modes of vibration
- Tests for chafing wires, cracked solder joints, material failures, loose parts and more
About MIL-STD-810 Method 514
Vibration, Method 514, is one of the more complicated—and interesting—aspects of MIL-STD-810 testing. This method has four procedures for different modes of vibration that a unit might withstand. We generally focus on procedures one and two, which address shipping or operational vibration.
This test looks for wires that might chafe, circuit boards that might crack solder joints or have damage, fatigue failures in metals or materials, and breakage and loose parts in the box. It’s meant to represent the entire lifetime of damage that a unit might endure to determine if a unit can live its life without damage or problems.
Within procedures one and two, there are more than 25 in-depth profile categories you can test to. We focus primarily on categories four, cargo, through 21, marine vehicles. Each category has a different vibration profile in terms of the spectrum, frequency and amplitude of energy that units are subjected to. Once you establish the procedure and the timeline, then you work through the category to identify the relevant application(s). Is it ground mobile? In a cargo application? An aircraft? Shipborne?
Crystal Group combines several different categories to qualify products for multiple platforms using one test. For instance, we might take the power spectro density associated with C-17, which is a very broad spectrum general turbine engine noise and overlay the propeller blades of a C-130. Then we may incorporate the ground mobile types of vibration seen in some of the lower frequencies. On top of that we might put in something like the Blackhawk. and combine all those profiles together.
Combining all of those profiles together establishes a worst-case scenario, which provides us the opportunity to build a more robust product that doesn’t crack solder joints, has a longer life, and can withstand field service so it’s there for the warfighter when they need it. It’s a bit conservative, but it provides a better end product that delivers greater reliability and uptime availability in the field.
Overall, there is a substantial amount of information in Method 514. There’s an entire tailoring section in Annex A and an engineering resource in Annex B. For those of us that are mechanical engineers or aerospace engineers, it’s very interesting.
