1、Lessons Learned Entry: 1392Lesson Info:a71 Lesson Number: 1392a71 Lesson Date: 2003-09-11a71 Submitting Organization: JSCa71 Submitted by: Dave T. Loyd/Angela Luna/Ronald A. MontagueSubject: Design and Operational Control Considerations for Steam Systems Abstract: Systemic management and technical f
2、ailures led to the catastrophic rupture of a test system. 3 lessons are published regarding this specific incident; this lesson addresses unique considerations for steam-based systems.Description of Driving Event: On September 11, 2003, at approximately 2:16 PM, the steam line on the Large Altitude
3、Simulation System (LASS) suffered a catastrophic failure of the 24-inch expansion loop located adjacent to the Test Stand 401 steam ejector exhaust duct. The LASS was being operated to verify its readiness to support an altitude firing of the 4th stage of a Minuteman ICBM scheduled for September 25,
4、 2003. The failure occurred approximately 16 seconds after the LASS was commanded to go to full steam, and resulted in a rupture of a portion of the line that dislocated several pieces of the 24-inch pipe in various directions away from the test stand. The proximate cause of the event was pipe wall
5、corrosion that led to selective thinning of the wall, which resulted in the pipe rupture under pressure. The investigation resulted in the following observations and conclusions: 1. Piping insulation, if not properly installed and maintained, can trap moisture on the exterior of the pipe and acceler
6、ate corrosion.2. If moisture is not removed from “non-continuous use” steam lines between use, the corrosive environment during the down time can be worse than during active use.3. Elevated levels of carbon dioxide in steam system water can lead to excessive amounts of carbonic acid which is highly
7、corrosive to carbon steel piping.4. Post implementation problem solutions must utilize a “systems approach” in order to avoid Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-creating other design issues beyond the immediate problem being corrected.Le
8、sson(s) Learned: Steam-based systems have unique issues that must be considered in their design, operation, and maintenance.Recommendation(s): 1. Establish the operational design, operation, and life requirements of the re-designed system as a basis for corrosion allowance determination.2. 3. Assure
9、 that an inactive system does not retain moisture in the steam lines. Suggested techniques include:2a. Draining all steam lines as soon as possible after a run. 2b. Purging the entire steam with dry inert gas between runs. 2c. Avoiding long horizontal steam line runs that may inhibit drainage. 2d. A
10、voiding valve locations that trap water. 3. Implement a method to neutralize the carbonic acid and remove the water from the pipe without removing the passivation-treated layer of the wall lining.4. Determine the feasibility of operating the system without exterior insulation on the steam lines to m
11、inimize exterior corrosion.5. Assure that the system contains voids, supports, guides, and restraints that would allow the steam lines to handle thermal expansion and thrust loading.6. Implement remote safing capability for facility systems.7. Assess the availability of PPE and atmospheric monitorin
12、g equipment in manned test monitoring facilities such as blockhouses.8. Assess the human factors design of control room console layouts, and facility system status displays to aide personnel in assessing facility conditions.9. Add external area status light indicators to blockhouses.10. Implement me
13、asures to renew the appreciation of the hazards associated with high-energy systems, and to the importance of understanding all aspects of high-energy facility systems condition, among personnel.11. Assure that Failure Modes Effect Analysis (FMEA) and Hazard Analysis (HA) reports are up to date and
14、accurate for the system prior to system pressurization. The HA must be reviewed as part of a Test Readiness review (TRR) or System Requirements Review (SRR.) Updates to the HA must be incorporated whenever changes are made to the hardware or operating procedures. Most importantly, the controls speci
15、fied in the Hazard Analysis must be verified to be in place before the activity commences.12. Assure thoroughness and follow-through in the SRR process for facilities.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-13. Establish a policy for when a T
16、est Readiness Review is required when conducting functional checkout operations on high-energy systems.14. Assure rigor exists in the Pressure Systems inspection program, including a process for tracking and follow-up on corrections for non-compliances.15. Conduct a review of facilities for which kn
17、own, documented degradation exists, which if left un-abated, could pose hazards to personnel and facilities. The primary objective of this review would be to identify candidate “emergency“ Construction of Facilities (CoF) projects that warrant accelerated schedules for correction.16. Review all faci
18、lities to assure that hazards are identified and documented in Hazard Analyses and that adequate controls are in place. Establish process to assure that the above activities are sustained over time.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: Generically to emergency
19、 planning, pressure systems processes, and design and operations documentsMission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Administration/Organizationa71 Configuration Managementa71 Emergency Preparednessa71 Energetic
20、 Materials - Explosive/Propellant/Pyrotechnica71 Energya71 Facilitiesa71 Ground Equipmenta71 Ground Operationsa71 Hardwarea71 Human Factorsa71 Industrial Operationsa71 Personal Protective EquipmentProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-a71 P
21、olicy & Planninga71 Pressure Vesselsa71 Program and Project Managementa71 Risk Management/Assessmenta71 Safety & Mission Assurancea71 Test FacilityAdditional Info: Approval Info: a71 Approval Date: 2004-04-26a71 Approval Name: Ronald A. Montaguea71 Approval Organization: JSCa71 Approval Phone Number: 281-483-8576Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
