05000335/LER-2013-001, Regarding Automatic Reactor Trip Due to Failure of the Lb Main Steam Isolation Valve

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Regarding Automatic Reactor Trip Due to Failure of the Lb Main Steam Isolation Valve
ML13142A200
Person / Time
Site: Saint Lucie NextEra Energy icon.png
Issue date: 05/10/2013
From: Jensen J
Florida Power & Light Co
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
L-2013-156 LER 13-001-00
Download: ML13142A200 (4)


LER-2013-001, Regarding Automatic Reactor Trip Due to Failure of the Lb Main Steam Isolation Valve
Event date:
Report date:
Reporting criterion: 10 CFR 50.73(a)(2)(i)

10 CFR 50.73(a)(2)(vii), Common Cause Inoperability

10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded

10 CFR 50.73(a)(2)(viii)(A)

10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition

10 CFR 50.73(a)(2)(viii)(B)

10 CFR 50.73(a)(2)(iii)

10 CFR 50.73(a)(2)(ix)(A)

10 CFR 50.73(a)(2)(iv)(A), System Actuation

10 CFR 50.73(a)(2)(x)

10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor

10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat

10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown

10 CFR 50.73(a)(2)(v), Loss of Safety Function

10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
3352013001R00 - NRC Website

text

0 FPL.

May_.10, 2013 L-2013-156 10 CFR 50.73 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Re:

St. Lucie Unit 1 Docket No. 50-335 Reportable Event: 2013-001.

  • Date of Event: March 12, 2013 Automatic Reactor Trio due to Failure of the 11B Main Steam Isolation Valve The attached Licensee Event Report 2013'001 is being submitted pursuant to the requirements of 10 CFR 50.73 to provide notification of the subject event.

Very truly yours, Sl'ucie Plant JJ/rcs Attachment Florida Power & Light Company 6501 S. Ocean Drive, Jensen Beach, FL 34957

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NRC FORM 366 U.S.

NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

3.

PAGE St. Lucie Unit 1 05000335 1 OF 3

4.

TITLE Automatic Reactor Trip due to Failure of the lB Main Steam Isolation Valve

5.

EVENT DATE

6.

LER NUMBER

7.

REPORT DATE

8.

OTHER FACILITIES INVOLVED MTY Y SEQUENTIA REV MONTH D

YA FACILITY NAME DOCKET RLNUMBER NO.M 3

12 2013 2013 001 00~ 5 10 2013 FACMBTNAM

9. OPERATING MODE
11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply)

El 20.2201(b)

El 20.2203(a)(3)(i)

El 50.73(a)(2)(i)(C)

El 50.73(a)(2)(vii) 1 El 20.2201(d)

El 20.2203(a)(3)(ii)

El 50.73(a)(2)(ii)(A)

El 50.73(a)(2)(viii)(A)

El 20.2203(a)(1)

El 20.2203(a)(4)

[I 50.73(a)(2)(ii)(B)

El 50.73(a)(2)(viii)(B)

[E 20.2203(a)(2)(i)

[I 50.36(c)(1)(i)(A)

El 50.73(a)(2)(iii)

El 50.73(a)(2)(ix)(A).

10. POWF. LEVEL El 20.2203(a)(2)(ii)

El 50.36(c)(1)(ii)(A)

[

50.73(a)(2)(iv)(A)

El 50.73(a)(2)(x)

El 20.2203(a)(2)(iii)

El 50.36(c)(2)

El 50.73(a)(2)(v)(A)

El 73.71(a)(4) 100%

El 20.2203(a)(2)(iv)

El 50.46(a)(3)(ii)

El 50.73(a)(2)(v)(B)

El 73.71(a)(5)

El 20.2203(a)(2)(v)

El 50.73(a)(2)(i)(A)

El 50.73(a)(2)(v)(C)

El OTHER El 20.2203(a)(2)(vi)

El 50.73(a)(2)(i)(B)

El 50.73(a)(2)(v)(D)

Specify in Abstract below or in limit switches could not be set as specified.

The resulting actions focused on limit switch setpoint adjustment and limit switch mounting changes to address the condition.

Safety Significance

The Conditional Core Damage Probability (CCDP) and Conditional Large Early Release Probability (CLERP) values were evaluated for the stated event and were found to be significantly below the thresholds required by RG-I.174 for the risk to be "Small" where CCDP is below 1.OE-06 and CLERP is below 1.OE-07. Given the response of the plant and the insignificant CCDP and CLERP values, the health and safety of the public were not affected by this event.

This reactor trip event is reportable pursuant to 10 CFR 50.73(a) (2) (iv) (A) as.an automatic actuation of the reactor protection system (RPS).

This event had no significant safety consequence since the Reactor Protection System successfully performed its intended safety function upon the failure of the lB Main Steam Isolation Valve.

Corrective Actions

The corrective actions listed below are entered into the site corrective action program.

Any changes to the actions will be managed under the corrective action program.

1. The tail links (including the spare) were reworked and full spindle travel to the back seat were verified for HCV-08-1A and HCV-08-1B.
2.

The Station will revise the maintenance procedure (and associated vendor manual) for Main Steam Isolation Valve disassembly, inspection, repair and reassembly to include steps to ensure that the valve opens completely until the spindle is on the back seat.

This will also include a caution that that the H-Link pins can be overloaded by the actuator if the valve does not open to the back seat.

Similar Events

A search of the corrective action database was performed and identified no similar issues that were related to the valve failures in this report.

Failed Component(s)

Main Steam isolation Valve Manufacturer The Unit 1 MSIVs were originally manufactured by Schutte & Koerting (S&K).

The replacement valve actuator is manufactured by Enertech.

The new valve internal components replaced in SLl-24 were manufactured by Flowserve based on Kalsi Engineering analysis.