1、Lessons Learned Entry: 0063Lesson Info:a71 Lesson Number: 0063a71 Lesson Date: 1992-03-06a71 Submitting Organization: KSCa71 Submitted by: David PenningtonSubject: Overheated Baking/curing Oven Temperature Control Description of Driving Event: During the cerachrome insulation baking process of three
2、 injector/chamber assemblies, severe oxidation of the assemblies was observed. The required baking temperature, per MTS 1324, is 600 deg F for 48 hours. It was discovered that the oven had failed, allowing the temperature to reach an estimated 1400 deg F. A proposed design change will reduce the pos
3、sibility of this happening again. The modification incorporates a direct 440 VAC cut-off initiated by series redundant over-temperature shutoff circuits, as well as, a series redundant shutoff of the temperature control.Lesson(s) Learned: Failure to utilize redundant overtemp cutoff circuitry may re
4、sult in damage to components undergoing baking/curing processes.Recommendation(s): Add a series redundant 440 VAC cut-off switch that is actuated by the temperature shutoff circuit sensor.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AProvided by IHSNot for ResaleNo
5、 reproduction or networking permitted without license from IHS-,-,-Mission Directorate(s): N/AAdditional Key Phrase(s): a71 Hardwarea71 Packaging Handling Storagea71 Parts Materials & ProcessesAdditional Info: Approval Info: a71 Approval Date: 1994-06-02a71 Approval Name: James G. Klinea71 Approval Organization: KSC/HEIa71 Approval Phone Number: 407-867-7614Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
