05000280/LER-1979-037-03, During Normal Operation, Routine Surveillance Revealed Failure of Heat Tracing Circuit 13A,1 & 2 Boron Injection Recirculation to Boric Acid Tanks.Caused by Excessive Heating of Heat Tracing Tape

During Normal Operation, Routine Surveillance Revealed Failure of Heat Tracing Circuit 13A,1 & 2 Boron Injection Recirculation to Boric Acid Tanks.Caused by Excessive Heating of Heat Tracing Tape

ML18136A467
Person / Time
Site:	Surry
Issue date:	12/11/1979
From:	Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML18136A464	List: 05000280/LER-1979-031-03, While Reviewing Liquid Waste Release Forms,Discovered That Liquid Waste Monitor Did Not Alarm High & Trip Release Valve During 791117 Isotope Activity Release.Caused by Personnel Error 05000280/LER-1979-035-03, Routine Surveillance Revealed Failure of Heat Tracing Circuit 2B,Unit 1 Suction Piping to Boric Acid Transfer Pump.Caused by Water Damage to Heat Tracing Circuit 05000280/LER-1979-037-03, During Normal Operation, Routine Surveillance Revealed Failure of Heat Tracing Circuit 13A,1 & 2 Boron Injection Recirculation to Boric Acid Tanks.Caused by Excessive Heating of Heat Tracing Tape ML18136A463
References
LER-79-037-03X, NUDOCS 8002070303
Download: ML18136A467 (2)

LER-1979-037, During Normal Operation, Routine Surveillance Revealed Failure of Heat Tracing Circuit 13A,1 & 2 Boron Injection Recirculation to Boric Acid Tanks.Caused by Excessive Heating of Heat Tracing Tape

Event date:
Report date:
2801979037R03 - NRC Website

text

NRC FORM 366 (7-l-:'),

U.S. NUCLEAR REGULATORY COMMISSION CONTROL BLOCK:

A LICENSEE EVENT REPORT A

~ ~~TED REPORT PRE~S REPORT DATE 12-11-79 I I J '1' (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

'--------'----"--~~-~-6 \\..'..)

~

I v I A I s I P I s I 1 I GL-1 _q.,___qL...........11-----1ol----1.0l ---1...oJ _o_._J _o....L.I _-J_I _o_.__l __,o 101 41 1 I 1 I 1 l 1101 I

I 0 7

8 9

LICENSEE CODE 14 15 LICENSE NUMBER 25 26 LICENSE TYPE

JO 57 CAT 58 CON'T.

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S

~:~~~ ~© I O I 5 I O I O I O I 2 I s I 0101 1 I 1 I 1 J 9 I 7 J 9 JG) I 1 I 2 I 1 J 1 I 7 I 9 I G) 60 61 DOCKET NUMBER 68 69 EVENT DATE 74 75 REPORT DATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES@

J During normal operation, routine surveillance revealed the failure of heat tracing circuit 13A (Panels 8 & 9) //1 & 112 Boron Injection Recirc to Boric Acid Tanks.

This i§

~

a degraded mode of operation permitted by T.S. 3.3.B.5, and is reportable as per T.S.

~

I 6.6.2.b. (2).

The health and safety of the public were not affected.

[§))]

7 8 9 [ill]

7 8

SYSTEM CODE

CAUSE

CAUSE CODE SUB CODE COMPONENT CODE COMP.

SUBCODE VALVE SUBCODE Is I HJ@ ~@ ~@ I HI EI A I T j E I R j@ Li ~@

9 10 Q

LER/RO LVENT YEft.R

~

REPORT 1 7 J 9 I NUMBER 21 22 11 12 13 SEQUENTIAL REPORT NO.

! o I 3 I 7 I 18 OCCURRENCE CODE I O I 3 I 19 REPORT TYPE

~

23 24 26 2 7 28 29 30 20 1-=1 31 ACTION FUTURE EFFECT SHUTDOWN 122)

ATTACHMENT NPRDA PRIME COMP.

TAKEN ACTION ON PLANT METHOD HOURS I\\)

SUBMITTED FORM !:>UB.

L:J@~@) L:J@ ~ I O I O I O I l L:J@ ~(§ 33 34 35 36 3 7 40 41 42 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS @

43 SUPPLIER

~@

REVISION NO.

LU 32 COMPONENT MANUFACTURER 80 IT 11 J 8 1 s I 44 47 lA review of the heat tracing circuit showed that failure was caused by excessive heatink [ill] I of the heat tracing tape.

The corrective action implemented was to rep}ace the heat [I))] l tracing tape, and to initiate a design change to.

correct the design deficiency.

7 8

9 FACILITY STATUS

% POWER OTHER STATUS METHOD OF A

80

~LJ@

11 0 I O l@)IL-_NA _____

DISCOVERY DISCOVERY DESCRIPTION ~

~@L-1 _E_l_e_c_t_r_1_* c_i_a_n_o_b_s_e_rv_a_t_i_o_n ________ __.

45 46 80 8

9 10 12 13 ACTIVITY CONTENT

~

RELEASED OF RELEASE AMOUNT OF ACTIVITY~

QTIJ LJ @) l:_J(§)..._J _ _

N_A _____

7 8

9 10 11 7

44 NA LOCATION OF RELEASE@

44 45 80 PERSONNEL EXPOSURES

~

NUMBER.

(:;;\\ TYPE DESCRIPTION 39 CITTI I ~ o1 ~u@L.__ __

N_. ______________________

8 9

11 12 13 80 NUMBER DESCRIPTION 41 PERSONNEL INJURIES

~

o=0 I 01 OJ OJ@)L_ ___

A ______________________

7 8

9 11 12 LOSS OF OR DAMAGE TO FACILITY '4J\\

TYPE

DESCRIPTION

'-::::J 80

~

L_:j~L.....-~_NA~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

B 9

10 BO PUBLICITY C\\

3 3 NRC USE ONLY ISSU~D DESCRIPTION~

0

<C [II§] u@L-.

1 _N_A __________

s_o_o_2_0_1_0 ___ :---___.

1 1 1 1 1, 1 1 1 1.1 1 1 ~

8 9

10 68 69 so*;

NAME OF PREPARER --...:l*,...r -IL---""S-'-t.:::

0 ci,r,r""'aur_,t __________ _

PHONE: (80(1) 375 3184 0

11 l'.)

i; I

(UPDATE REPORT)

(ATTACHMENT), PAGE 1 OF 1 SURRY POWER STATION, UNIT 1 DOCKET NO: 50-280 REPORT NO: 79-037/03X-l EVENT DATE:

11 /19 /79 TITLE OF EVENT:

Low Current on Heat Tracing

1.

DESCRIPTION OF EVENT

With the unit in normal operation at rated power, operator surveillance found that Heat Tracing Circuit 13A was operating at less than the*current specified in the surveillance document.

No low temperature alarms were indicated.

Investigation.for faulty. heat. tracing.tape was. initiated on the affected.

circuit.

Faults were found on circuit 13A (panels 8, 9) l,!l & 1,12 Boron Injection recirculation to the Boric Acid Tank and were identified as being the result of excessive heat.

The tape was replaced and circuit current verified to be within specs of the surveillance document.

This is a

degraded mode of operation permitted by T. S.

3. 3. B. 5 and is reportable in accordance with T.S. 6.6.2.b.(2).

2.. PROBABLE CONSEQUENCES AND STATUS OF REDUNDANT SYSTEMS:

3.

At al 1 times during the event, the temperature of the affected line was maintained as required.

The redundant circuit was operable.

There were at all times two operable flow paths for boric acid to the reactor.

Therefore, the health and safety of the public were not affected.

CAUSE

The reduced currents were due to excessive heating of the hea*t tracing tape through poor circuit design.

4.

IMHEDIATE CORRECTIVE ACTION:

The heat tracing tape was replaced.

5.

SCHEDULED CORRECTIVE ACTION:

The problem was corrected immediately and a

design change has been initiated to correct a design deficiency.

6.

ACTION TAKEN TO PREVENT RECURRENCE:

Continuous surveillance is maintained on the Heat. Tracing System.

No additional action is considered necessary.

7.

GENERIC IMPLICATIONS:

In view of the number of failures of this heat tracing tape, a task force has been established to examine the heat tracing system and de tennine corrective action.