1、Lessons Learned Entry: 0454Lesson Info:a71 Lesson Number: 0454a71 Lesson Date: 1991-07-30a71 Submitting Organization: JSCa71 Submitted by: S. MartinSubject: Assembly of Vacuum Vent Valve Description of Driving Event: The excessive torque problem was due to improper assembly. The mechanical stop moun
2、ting screws were loose permitting the mechanical stop to move away from the housing toward the control housing.Lesson(s) Learned: Improper torquing of the Waste Collection System (WCS) vent valve knob retention screw caused the knob to work its way off the shaft.Recommendation(s): Add mandatory insp
3、ection point to procedure to verify mechanical stop mounting screws are properly torqued.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: N/AMission Directorate(s): Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/AAddit
4、ional Key Phrase(s): a71 Hardwarea71 Safety & Mission AssuranceAdditional Info: Approval Info: a71 Approval Date: 1996-09-30a71 Approval Name: Ron Montaguea71 Approval Organization: JSC/NA3a71 Approval Phone Number: 281-483-8576Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
