• Thank you for visiting the Cafe Rad Lab Forum
  • We present & discuss radiation health, science & news
  • To keep you informed about vital nuke information.
Hello There, Guest! Login Register


NPS_Watch Feb 25, 2019
#1
The Daily Dose - Exposing the nuclear power industry while the nuclear power industry exposes you.

There are 10 EN(s) today, 4 associated with power stations.

[ Three reactor problems and a PART21. ]

NRC Event Notices for February 25, 2019 |
https://www.nrc.gov/reading-rm/doc-colle...225en.html

{ }

----------------------------------------------------------------------------------------------------------------------------------------------------
----------------- Power Reactor Event Notices
----------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------------------------------
----------- [ Current event for OH_Perry_1 ]


20190225 | OH_Perry_1 | AUTOMATIC REACTOR SCRAM DUE TO GENERATOR TRIP |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53896

"At 0024 EST on 2/25/19, with Unit 1 in Mode 1 at 74 percent power,
the reactor automatically tripped due to a generator trip.

The trip was not complex, with all systems responding normally post-trip.

"Operations responded and stabilized the plant.

Reactor water level is being maintained via the feed system.

Decay heat is being removed by discharging steam to the main condenser using the turbine bypass valves.

"Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour,
non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B).

"There was no impact on the health and safety of the public or plant personnel.

The NRC Resident Inspector has been notified."

The generator trip is under investigation, but is believed to be due to grid perturbations.


----------- [ 2019 event history for OH_Perry ]

[ No previous ENs for this year. ]


[ 24 mnth RFO cycle, next Sched RFO 20190309 ]

----------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------------------------------
----------- [ Current event for MS_GrandGulf_1 ]

20190223 | MS_GrandGulf_1 | AUTOMATIC REACTOR SCRAM AFTER TURBINE CONTROL VALVE FAST CLOSURE |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53894

"Actuation of RPS [Reactor Protection System] with the reactor critical.

Reactor scram occurred at 1458 [CST] on 2/23/2019 from 100% power.

The cause of the scram was due to Turbine Control Valve Fast Closure.

"All control rods are fully inserted.

Currently reactor water level is being maintained by the Condensate Feedwater System in normal band
and reactor pressure is being controlled via Main Turbine Bypass valves to the main condenser.

No ECCS [Emergency Core Cooling System] initiation signals were reached and no ECCS or Diesel Generator initiation occurred.

"The Low-Low Set function of the Safety Relief Valves actuated upon turbine trip.

This was reset when pressure was established on main turbine bypass valves.

"The cause of the turbine trip is still under investigation.

"There were no complications with scram response."

The licensee notified the NRC Resident Inspector.

There was no maintenance occurring on the main turbine at the time of the scram.


----------- [ 2019 event history for MS_GrandGulf ]

20190213 | MS_GrandGulf_1 | FITNESS FOR DUTY - ENTERGY NON LICENSED SUPERVISOR FAILED TO REPORT FOR FITNESS FOR DUTY TEST |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53870



----------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------------------------------
----------- [ Current event for GA_Hatch_2 ]

20190223 | GA_Hatch_2 | AUTOMATIC ACTUATION OF 2C EMERGENCY DIESEL GENERATOR |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53893
[ RFOD_020; RX_Mode; Refueling; Refueling ]

"At 0212 EST on February 23, 2019, with Unit 2 in Mode 5,
an actuation signal for the 2C Emergency Diesel Generator (EDG) was received
during the Loss of Coolant Accident / Loss of Offsite Power logic system functional test.

The 2C EDG was running and tied onto the 2G 4160 emergency bus when the alternate supply breaker was closed
as required per the test procedure.

Immediately upon closing the alternate supply breaker, both the alternate supply breaker and 2C EDG output breaker tripped open.

The 2C EDG output breaker reclosed once the 2G 4160 bus undervoltage relays sensed a deenergized bus.

When the 2C EDG tied to the 2G 4160 bus, the bus voltage was noted as being high, and the 2C EDG was secured.

Investigation is ongoing to determine the cause of the initial bus undervoltage and the subsequent bus excessive voltage.


"This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A)
as an event that results in a valid actuation of the emergency AC power system.

"There was no impact on the health and safety of the public or plant personnel.

The NRC Resident Inspector has been notified."

This event puts Unit 1 in a 72 hour Limiting Condition for Operation for the 1C Startup Transformer being out of service.


----------- [ 2019 event history for GA_Hatch ]

20190212 | GA_Hatch_1;2 | PART 21 - EATON A200 STARTERS DID NOT OPEN WHEN POWER WAS REMOVED |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53867

20190211 | GA_Hatch_1;2 | Update POTENTIAL PART 21 INVOLVING A200 SERIES STARTERS |
https://www.nrc.gov/reading-rm/doc-colle...ml#en51611

20190204 | GA_Hatch_2 | GA_Hatch_2 @ 0 % [ Begin RFO (   / 20 ) ] [ orig 20190206 shutdown early ]


20190108 | GA_Hatch_1;2 | INVALID SPECIFIED SYSTEM ACTUATION |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53817

----------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------------------------------
----------- [ Current event for
----------- [ 2019 event history for
[ No previous ENs for this year. ]

----------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------------------------------
------------[ PART 21 ]
----------------------------------------------------------------------------------------------------------------------------------------------------

20190222 | no units identified | PART 21 REPORT - FLOWSERVE VALVE ASSIST SPRINGS MAY PREVENT FULL CLOSURE |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53891


PART 21 REPORT - FLOWSERVE VALVE ASSIST SPRINGS MAY PREVENT FULL CLOSURE

The following report was received via fax:

"Description: GE BWXT, acting on behalf of Ontario Power sent five valves back to the Flowserve facility for evaluation of the spring which could spread apart when the flapper rotates open and wedge between the valve body and flapper, creating the potential for the valve flapper to stick open.

"Evaluation: Shop inspections of the returned valves confirmed the potential for the spring legs to rotate outwards and potentially wedge between the flapper and seat retainer. Of the five valves evaluated, two of the valves had the spring legs rotate outward and after repeated cycles got caught between the flapper and disc; on one of the instances the spring legs prevented full closure of the flapper.

"If the valves have a safety-related function to isolate flow and must transfer closed, then the springs could prevent the valve from performing its safety related function.

"The evaluation determined the cause is an inadequate spring design which allows the spring to deflect and permit the legs to move outward.

"Extent of Condition: In discussion with the customer, it is believed the problem did not exist with valves originally supplied from the Worcester, Scarborough Canada facility; although this cannot be confirmed by Flowserve. It is believed the extent of condition resides with valves and replacement springs supplied from the Flowserve Raleigh, NC facility when the product line was transferred and the spring vendors changed; even though it has been confirmed that the springs supplied out of the Raleigh, NC facility comply with the product drawing requirements. The springs were first sold in valve assemblies or as replacement parts from the Raleigh facility starting in 2008.

"Valve Scope: The scope of impacted valves is the Worcester series 44 swing check valves. (Please note Worcester also has a series 44 three piece ball valve, which is not in the scope.} The Raleigh facility has supplied parts or valves for four Worcester series 44 swing check valves assemblies which use these springs. The drawings numbers for these valve assemblies are listed below:

Drawing Valve Size Customer
KN44-0590 1.5 X 1 X 1.5 Bruce Power, GE BWXT & Ontario Power
KN44-0630 2 Comanche Peak
14-107362-001 1.5 X 1 X 1.5 GE BWXT
16-118733-001 1.5 X 1 X 1.5 GE BWXT

"Corrective Actions:
1) Owner's may remove the springs. The valves will check-off and seal under low pressure conditions without the assistance of the spring; this was demonstrated in shop tests using tap water pressure (approximately 60 psig) and will initiate closure when full open without the assistance of the spring.
2) Flowserve is evaluating alternate spring designs along with the possibility of adding guides to prevent the undesired spring movement. Any new design will be proof tested.

"Respectfully submitted, [ redacted contact info on NRC site. ]


----------------------------------------------------------------------------------------------------------------------------------------------------
----------------- Other reactor info from daily power tracking
-----------------------------------------------------------------------------------------------------------------


Region 1
 
MD_Calvert_Cliffs_2 @ 0 % [ RPV OPEN ( 08 / 22 ) 20190218 ]

NY_Nine_Mile_Point_1 @ 89 % [ coastdown to RFO 20190320 ]

NJ_Oyster_Creek_1 @ 0 % [ RPV CLOSED , defueled , permanent shutdown ]

NJ_Salem_1 @ 97 % [ coastdown to RFO 20190426 ]

PA_Susquehanna_2 @ 88 % [ coastdown to RFO 20190323 ]


Region 2

AL_Browns_Ferry_1 @ 65 % down from 100 % Sunday; 100 % Saturday
[ No EN, reason for power drop unk. ]

AL_Browns_Ferry_2 @ 88 % [ coastdown to RFO 20190302 ]

AL_Browns_Ferry_3 @ 98 % up from 67 % Sunday; 100 % Saturday
[ no EN, reason for power drop unk. ]

NC_Brunswick_2 @ 99 % down from 100 % Sunday
[ coastdown to RFO 20190302 ]

AL_Farley_1 @ 0 % [ ( 06 ) no EN, reason for shutdown unk ]

GA_Hatch_2 @ 0 % [ RPV OPEN ( 22 / 20 ) ] [ 20190204 shutdown early ]

VA_NorthAnna_2 @ 94 % [ coastdown to RFO 20190303 ]
 PART 21 - EATON A200 STARTERS DID NOT OPEN WHEN POWER WAS REMOVED |
 https://www.nrc.gov/reading-rm/doc-colle...ml#en53867

FL_Turkey_Point_4 @ 98 % [ coastdown to RFO 20190311 ]

GA_Vogtle_2 @ 98 % [ coastdown to RFO 20190310 ]


Region 3

IL_Clinton_1 @ 98 % unch from 98 % Sunday; 94 % Saturday
[ units normal operating range ]

MI_DC_Cook_1 @ 87 % [ coastdown to RFO 20190306 ]

IL_La_Salle_2 @ 0 % [ RPV OPEN ( 08 / 35 ) 20190218 ]

MN_Monticello_1 @ 87 %  [ coastdown to RFO 20190413 ]

OH_Perry_1 @ 0 % down from 75 % Sunday [ coastdown to RFO 20190309 ]
[ ref EN posted above. ]

IL_Quad_Cities_1 @ 95 % [ coastdown to RFO 20190318 ]


Region 4

MO_Callaway_1 @ 89 % up from 72 % Sunday; 100 % Saturday
[ no EN, unk reason for power down. ]

CA_DiabloCanyon_1 @ 0 % [ RPV OPEN ( 16 / 33 ) ] 20190210 ]

LA_RiverBend_1 @ 75 % unch from 75 % Saturday
[ coastdown to RFO 20190329, coastdown breakdown ]

LA_Waterford_3 @ 0 % [ RPV OPEN ( 52 / 39 )  ]
[ passed planned restart date ]

----------------------------------------------------------------------------------------------------------------------------------------------------

[ There is/are currently 5 unit(s) with the RPV OPEN - ref the 2019 Spring Refueling Outage Schedule and Status ]

posted by Staup Knewkinus a Dane Gerous production. All human rights reserved.
 
Reply
  


Forum Jump:


Browsing: 1 Guest(s)