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NUREG Investigation Report No. NUREG-IN-94-51 1994 Operational Operational
NRC 信息公告 94-51:双密封电机轴承不当加脂导致启动失败(1994,North Anna)
North Anna Power Station, Virginia, USA (Dominion / Virginia Power)
Related equipment type → electric motor (electric motor)
0Fatalities
0Injuries
FailureMechanism code FAI
Failure Mode · ISO 14224 Mapping
Damage mechanism (recorded in KB)
FailureFAI
Internal damage-mechanism code (not ISO 14224)
ISO 14224:2016 functional failure code
OTH · Other
Mapped to ISO OTH — Other.
1What Happened

EDG 燃油输送泵电机因轴承内过量润滑脂在低温下变硬,启动电流过大、热过载脱扣,电机无法加速至额定转速;其中一台 EDG 因备用泵亦失效被宣布不可用

2Root Cause

双密封轴承本不需加脂,但自 1986 年起每 18 个月加脂,旧脂充满轴承腔;低温下脂硬化致启动负载异常升高

3Reliability Lessons (from investigation root cause)
  • The 'Root Cause' above is the core lesson of this accident; not split further.
4Associated Failure Mechanisms (Keywords)
电机 轴承 润滑脂 加脂 启动失败 过电流 低温 electric motor bearing grease locked rotor overload
About the Failure-Mode Code (click to expand)

The mechanism code FAI shown on this card is the KB's internal damage-mechanism abbreviation (not an ISO 14224 code); it describes how the equipment failed. The 'ISO 14224 Mapping' block above maps it to the correct ISO functional failure code (which describes what the equipment failed to do) — these are two distinct dimensions in ISO 14224. The mechanism follows the narrative in the card body.

5Evidence Source (transparent)
Authority:U.S. Nuclear Regulatory Commission (NRC), Division of Operating Reactor Support
Official Report:www.nrc.gov ↗
Data Verification:verified_url_nrc_adams_ML031060599_2026-08-08 (NRC IN 94-51 PDF 原文)
Related Failure Modes · Traceability
轴承内圈缺陷 bearing_inner_race_defect轴承外圈缺陷 bearing_outer_race_defect滚动体缺陷 bearing_ball_defect定子绕组绝缘老化 stator_winding_insulation_aging定子绕组匝间短路 stator_winding_turn_short转子断条 rotor_bar_broken转子不平衡 rotor_unbalance轴不对中 rotor_misalignment过热绝缘烧毁 overheating_insulation_burn润滑脂劣化 lubrication_grease_degradation润滑油污染 lubrication_oil_contamination冷却风扇失效 cooling_fan_failure接线盒端子松动 terminal_box_loose_connection基础松动振动大 vibration_excessive_foundation轴电流电蚀 bearing_current_erosionGear-tooth Pitting gear_tooth_surface_pitting齿根疲劳断裂 gear_tooth_root_fatigue_crack齿面磨粒磨损 gear_tooth_wear_abrasive齿面胶合/擦伤 gear_tooth_scuffing齿轮箱轴承内圈缺陷 gb_bearing_inner_race_defect齿轮箱轴承外圈缺陷 gb_bearing_outer_race_defect不对中齿面偏载 gear_misalignment_tooth_load润滑油降解 gb_lubrication_oil_degradation润滑油污染 gb_lubrication_oil_contamination密封泄漏漏油 seal_leak_oil联轴器不对中 coupling_misalignment箱体裂纹 housing_crack键槽剪切失效 keyway_shear共振 vibration_resonanceIGBT 功率模块失效 igbt_power_module_failure直流母线电解电容老化 dc_bus_capacitor_aging冷却风扇失效 cooling_fan_failure控制板/固件死机复位 control_board_firmware_crash共模电压致电机轴承电蚀(轴电流) harmonic_bearing_current参数漂移/误整定误跳车 parameter_drift_spurious_trip输入整流桥二极管失效 rectifier_diode_failure直流母线过压(再生能量未泄放) dc_bus_overvoltage输出侧电缆/绕组绝缘因 dv/dt 退化 output_cable_insulation_degradation散热器热阻升高(积灰/导热硅脂老化) heat_sink_thermal_resistance_rise接地故障检测误动/拒动 ground_fault_protection_nuisance与 DCS/SIS 通讯中断 communication_loss柜体环境腐蚀/凝露 enclosure_environment_corrosion预充电电路失效 precharge_circuit_failureFTS fail_to_start带载失败 fail_to_accept_load冷却系统失效 cooling_failure润滑油系统故障 lube_oil_failure燃油污染/含水 fuel_contamination启动蓄电池失效 starting_battery_failure超速 overspeed电压调节器故障 voltage_regulator_fault排气阻塞 exhaust_restriction异常振动 vibration_abnormal增压器失效 turbocharger_failure控制系统故障 edg_control_fault
Report No. NUREG-IN-94-51 · Data from NUREG (US NRC) public investigation conclusions, compiled by Reliability AI, for reliability demonstration purposes only. This case is derived from public incident investigation reports for learning purposes only. AIM does not endorse or guarantee its accuracy.