1、Lessons Learned Entry: 0009Lesson Info:a71 Lesson Number: 0009a71 Lesson Date: 1991-06-14a71 Submitting Organization: JSCa71 Submitted by: T. MichaelSubject: Lubricant Particles Clogging Spacecraft System Filters Description of Driving Event: Low flow rates were observed in the shuttle orbiter freon
2、 coolant loops when the temperatures in the radiator panels dropped below minus 60 degrees Farenheit during a mission. An investigation of the problem revealed that the system filters were clogged with teflon particles. The origin of the particles was traced to the krytox fluoropolymer thread lubric
3、ant grease used during loop assembly. Corrective actions were taken to remove, clean, and replace the system filters, several valves, a flow proportioning module, and a pump assembly.Lesson(s) Learned: Use of assembly lubricant materials with suspended particles too large to pass through system filt
4、ers can cause clogging of the filters and reduce flow rates below minimum requirements in critical spacecraft systems.Recommendation(s): Contaminated system components were disassembled, cleaned, and replaced.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AProvided b
5、y IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Mission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Flight Equipmenta71 Launch Vehiclea71 Parts Materials & Processes Additional Info: Approval Info: a71 Approval Date: 1993-09-10a71 Approval Name: Ron Montaguea71 Approval Organization: JSC/NS3a71 Approval Phone Number: 281-483-8576Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
