PartsReuse_CriteriaForPartsReuse

“Can parts from space flight hardware be salvaged and reused?”

The following information is taken from "Salvage and Save." NASA Safety Center. Case of Interest. September 2013.

An incident occurred at a NASA Center that involved non-flight Hubble Space Telescope hardware. During testing, the vibration test table lunged upward at a high rate and expelled extremely high loads into the berthing pins, soft capture mechanism, berthing latches and scuff plates. Incidents like this one lead to the question, “Can parts from space flight hardware be salvaged and reused?”

The question also applies to parts that were used previously, but never failed. For example, consider microgravity experiments that are deployed on the Space Station, then returned to their origin. It is common for parts and systems such as cameras, power supplies, instrumentation, recording devices, and mechanical pieces to be returned to the NASA Centers where they were fabricated and tested. Can they be reused?

Many of these components and systems come back in various conditions. Some are completely worn out and unusable where others are “like new” and in perfect working order. If a part is subjected to harsh environments for long periods of time, it is more likely to experience degraded performance, and therefore not be salvageable.

Parts can be salvaged only if certain disciplines and procedures are executed to ensure the selected parts are processed adequately, and the technical staff are convinced that the parts will serve their function as originally designed.

The actual failure that occurred with the Hubble hardware is an extreme case. Not only are there failed parts and evident damage, but parts that were exposed to extreme conditions that could have weakened them, making them unusable or nonconforming. However, not all situations are so obvious—looks can be deceiving. Just because hardware looks like new and shows no obvious signs of damage or wear, does not mean it is okay to use.

Before hardware can be salvaged or reused, it must go through careful review by technical experts. This is done by processing hardware through a Material Review Board (MRB) or a special review board set up to examine specific hardware. The team usually includes design, quality and process engineers that get together and make decisions on what course of action is needed to qualify parts as fit for use.

 

Considerations

Salvaged parts should be handled like nonconforming material until they are processed according to established procedures and able to pass the specified inspections and tests. Testing should not only include tests for reuse, but also flight qualification tests to ensure parts are usable and appropriate for the new design. It is important to document decisions on how to handle the hardware. Items under consideration for reuse should be identified with appropriate documentation that tracks the decision making process as well as the inspections and tests performed to assist with qualifying the hardware for use. Documentation also should include any processing necessary to bring the hardware into conformance (i.e., a useable condition). Items not worth saving should be marked as scrap and discarded based on MRB procedures.

Documentation is an important element when dispositioning hardware for reuse. It is the pedigree data that captures the technical thought processes used to judge hardware and determine whether it is useable or not.

Part configuration and identification is another element to consider when salvaging parts. To qualify a part for use, it must be identified as a used part and traceable to completed work and testing. Typically, the part number is given a dash number or alpha character to signify that it has been used previously; this ensures the history can be located and that the part is distinguishable from new hardware.

Furthermore, disassembly and assembly procedures should be written by process engineers, and qualified personnel should handle disassembly and assembly. Also, inspection and test points should be applied, and results should be recorded and reported.