ENS 48380

From kanterella

Jump to navigation Jump to search

v t e ENS Event
04:00 Feb 21, 2012
Title	Steam Generator Tube to Tube Wear
Event Description	The following information was received via email: Mitsubishi Heavy Industries, LTD (MHI) has identified steam generator tube wear for San Onofre Nuclear Generating Station. Steam Generator tube wear has been identified in areas of the U-bend between anti-vibration bars, where the tube is not supported by the anti-vibration bars. This tube wear occurred due to the contact of a tube with an adjacent tube, and resulted in a leak from a Unit 3 tube. The cause of the tube leak was determined to be the in-plane direction fluid elastic instability under high localized thermal-hydraulic conditions (steam quality (void fraction), flow velocity and hydro-dynamic pressure), and insufficient contact force of the tube to anti-vibration bar. This type Mitsubishi Heavy Industries has identified steam generator tube wear for San Onofre Nuclear Generating Station. The Steam Generator tube wear adjacent to the retainer bars was identified as creating a potential safety hazard. The plugging of the tubes that have the possibility of the fluid elastic instability and thermal power output reductions were identified as potential corrective actions. SCE [Southern California Edison] will run Unit 2 at 70% power for a short duration as a corrective action. In addition, SCE and MHI will continue a detailed analysis and investigation to this problem. Additional corrective actions may be required as the analysis and investigation continue. MHI has recommended to the purchaser that it perform eddy current inspection of tubes after Unit 2 operation resumes.

ENS 48380 +/-
Where
Mitsubishi Heavy Industries, Ltd. Arlington, Virginia (NRC Region 1)
Organization:	Mitsubishi Nuclear Energy Systems
Reporting

10 CFR 21.21(d)(3)(i), Failure to Comply or Defect
Time - Person (Reporting Time:+5452.28 h227.178 days <br />32.454 weeks <br />7.469 months <br />)
Opened:	Joseph Tapia 07:17 Oct 5, 2012
NRC Officer:	Dong Park
Last Updated:	Oct 5, 2012
48380 - NRC Website
v • d • e

v t e Emergency Notification System
Mitsubishi Heavy Industries, Ltd. with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect
WEEKMONTHYEAR2012-02-21T04:00:00 [Table view]
[ENS list for Mitsubishi Heavy Industries, Ltd.]

Retrieved from "https://kanterella.com/w/index.php?title=ENS_48380&oldid=423570"

ENS Notification