Friday, May 16, 2014

Westinghouse RCP


A 4000hp motor???


(DelawareOnline) Eight thumb-sized, broken bolt-heads have sidetracked PSEG Nuclear's plans

for restarting its Salem Unit 2 nuclear reactor, as investigators work to find the breakaway spots and reasons for failure.
Discovery of the broken reactor coolant pump parts during a routine refueling outage prompted
Company spokesman Joe Delmar said Wednesday afternoon that PSEG was being conservative in delaying its restart to allow "additional internal inspections of the coolant pumps and make any repairs as needed." the company to extend the shutdown, which began April 14. It was the latest in a string of problems at the Salem/Hope Creek nuclear complex.
Nuclear Regulatory Commission spokesman Neil Sheehan said the bolt tops, each about an inch in diameter and 3 inches long, are likely from the area of one of four reactor coolant pump's impeller vanes, or blades.
Investigators consider "stress-corrosion cracking," – a kind of failure that occurs in some types of metals exposed to particular types of stress, temperature and corrosive conditions – as one of the potential causes for the breaks, Sheehan said.
"The concern is that if bolts holding the turning vane failed, the vane could drop and impact the rotating pump internals," Sheehan said.

According to this information release, the turning vane diffuser is the problem. There are bolts that secure the turning vane diffuser to the upper flange also hold the thermal barrier can assembly in place. The issue could end up being equal to a locked rotor accident, which has never happened. A locked rotor accident challanges the peak clad temperatures more than any one accident.
Flywheels on these 7-8K HP pumps are about the same weight as a heavy duty pickup, about 8K lbs. Not much can challange the costdown of these pumps, except a locked rotor. The lower radial bearing has been know to fail (ancient history), and the motor has enough power not phase it.
This is a very isolated issue, based on manufacture date and material used.

westinghouse

 
 
 
 
 Byron Jackson, CE
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Thursday, May 15, 2014

Hinsdale Sectectmen see the light: Hinsdale Bridges.

Tappan Zee bridge: ( 58 year old) Construction started in March 1952 and the bridge opened for traffic on December 15, 1955, along with a 27-mile (43 km) long section of the New York State Thruway from Suffern to Yonkers.[15][16] New York State Governor W. Averell Harriman signed a bill on February 28, 1956, to name the structure officially the Tappan Zee Bridge. 







TARRYTOWN, N.Y. — President Obama came to this Westchester County village on Wednesday to use the three-mile-long Tappan Zee Bridge as a backdrop to pressure Republicans in Congress to support infrastructure spending.
The White House argues that unless the president’s new $302 billion, four-year transportation program is passed, current transportation funding will run out later this year, endangering 112,000 highway, port and bridge projects, 5,600 transit projects and nearly 700,000 jobs....
I got s tremendous amount of heat with my wife, daughter, son and grandchildren over my activities at the bridge. There were rumors of divorcing me again. The theme was mike, you are acting like you are nuts. I afraid people will think I am nuts with staying married to you. I didn’t think my family seen the big picture with what I was doing. I got a really lot of shit from my family. I got a lot of shit from the people pass by me near the bridge.
Circa the summer of 2013, I knew all the selectmen were getting a tremendous pressure about the crazy halo man at the bridge. My activities were designed to do exactly than. I gave two presentations to them...the last one being the most contentious. I wish the final one could have been friendlier.

Clock ticks on bridges linking Brattleboro, Hinsdale 
Local, state officials seek to get deteriorating spans onto 10-year plan

I was talking to my lawyer in the winter. I asked him to talk with all the selectmen and the NHDOT officials. He told me he had investigators calling the selectman. The town official either didn’t take the call or could never say anything positive about bridge nut in a court. I was smart enough to know there is more than one objective in a court case.  I was using a form of power or influence...I knew by just getting the investigators to pester them I might be able to influence or manipulate them independent of a court case. I knew they are would be worried about how big this thing could get. They all knew and I told them I am a folk hero or heading to be one...100,000s of people seen my antics at the bridge. I am making a clear image on all of their minds.
I hammer the selectman over and over again last summer, you got to do something more than just sitting there. You got to write letters or complaints to the NHDOT or the governor. Talk to media.  


You tell me, did my lawyers activities precipitate this selectman’s letter.   


May 9, 2014: I'll leave you with one final thought. If you can’t trust the state (NHDOT) to do the right thing (replace and re-nail the boards) in the heat of my activities surrounding last July 31, 2013, how can you trust the state to do the right thing and make accurate bridge inspections (Hinsdale) during the intense political heat surrounding the NHDOT budgets?

By Meghan Foley Sentinel Staff
SentinelSource.co
HINSDALE — Now that a project to replace the two bridges connecting Hinsdale to Brattleboro is back on the table, Hinsdale selectmen want to make sure it stays there.
And that has prompted the board to request the N.H. Department of Transportation increase inspections of the nearly 95-year-old structures.
Late last month, the board sent a letter to the state agency asking it to more frequently inspect the 1920 Pennsylvania truss bridges, one of which connects Hinsdale to Hinsdale Island, and the other, Hinsdale Island to Brattleboro.
Board members made the request because they want to be sure the bridges aren’t deteriorating any further, and that the project to replace them is kept on the N.H. Department of Transportation’s 10-year transportation improvement plan, Town Administrator Jill E. Collins said Wednesday.
The Hinsdale bridge replacement project had been part of the transportation improvement plan since fiscal year 1994, but was bumped from the 2013-22 plan because of lack of funding.
The new draft plan, which covers 2015-24 and includes the Hinsdale bridge, was approved by the N.H. House in March, and is awaiting approval from the N.H. Senate.
According to the plan, one bridge would replace the two spans. The single-span bridge would be to the south of the existing ones, and be built in 2021-22. The project is estimated to cost $45.7 million.
By then, the bridges, which were last rehabilitated in 1988 and are considered functionally obsolete, will be 101 years old.
Functionally obsolete means the bridges are outdated, don’t meet current design standards, are narrow and have height and weight restrictions.
In comparison, the Memorial Bridge, which carried Route 1 over the Piscataqua River connecting Portsmouth and Kittery, Maine, was 89 years old and when it was taken out of service in 2012 to be replaced.
Closer to home, the bridge carrying Route 9 from West Chesterfield to Brattleboro over the Connecticut River was 66 years old when it was closed to motor vehicle traffic in 2003 following the opening of a new bridge next to it.
The bridges connecting Hinsdale and Brattleboro are called the Charles Dana and Anna Hunt Marsh bridges, and efforts to replace or rebuild them have been on-again, off-again since the early 1970s.
They’re inspected by state Department of Transportation officials on a two-year cycle, which is standard for all state- and municipal-owned bridges, Mark W. Richardson, administrator for the state agency’s bridge design bureau, said Tuesday.
His office received a letter from the Hinsdale selectmen, and is preparing a formal response, he said.
“There is much to consider regarding this request, most importantly is the safety of the traveling public,” he said.
They also have to evaluate whether the bridge maintenance crew has the resources to commit to the additional inspections, he said.
The Hinsdale bridges are ranked in fair condition, which is a five out of nine on the system used by the state agency, but are one step away from being added to the state’s red list.
A bridge makes the red list when one or more of its major structural elements has an inspection ranking of four or less, Richardson said.
That ranking means the bridge’s deck or another structural element is in poor condition with advanced section loss, deterioration, spalling or scour, he said.
Spalling is when small sections separate from the main body of a girder, deck or pier because of deterioration in the concrete, he said.
“Spalling usually does’t require a load reduction or posting, but it does indicate that the concrete ... is deteriorating, which can be a real safety concern if traffic travels under the bridge,” he said.
A bridge getting a ranking of three means that parts of it could fail, and a bridge could be closed when it reaches a ranking of two, he said.
State red-list bridges are inspected twice a year, while municipal red-list bridges are inspected once a year, he said.
“We are well aware of the attention that (Hinsdale-Brattleboro) bridges have received and strive to ensure that they are in such a condition that they can remain open for public use,” he said.
Even if his office determines it can handle more frequent inspections of the Hinsdale-Brattleboro bridges, that won’t translate into a shorter wait time on the state’s improvement plan, he said.
Meghan Foley can be reached at 352-1234, extension 1436, or mfoley@keenesentinel.com. Follow her on Twitter @MFoleyKS.

Wednesday, May 14, 2014

Palisades PCP Impeller Inspection

As a note, I continuously update this entry and revise it.

May 28:
Democrat Paul Clements says Congressman Fred Upton is no longer a moderate Republican
Who he won't take money from
Clements did not rule out taking money from interests outside Michigan, but he said there are certain groups from whom he would not accept campaign contributions. 
"I wouldn't take money from the Koch brothers, but I doubt they would want to give it to me," he said. 
He also said he wouldn't take money from Entergy Corp., the owners of Palisades Nuclear Power Plant in Covert Township. 
Palisades is "one of the most fragile, most accident-prone nuclear plants in the country," he said. "We need to be confident it is providing safe nuclear power or that it is moving toward a reasoned phase-out. We don't see that today – I think it represents a threat to us today and so I would not be comfortable accepting contributions from the company that owns it."


May 28:
May 26: Yep...the the extremist pro nukies ganged up on me and got me kicked off. I won't participate being moderated.

Note: It sure looks like Madalina has shifted me to a approving comment mode or worst. Or it could be issues with my computer or with Linkedin itself slowing down. But this has been going on for days so I find that unlikely.
"Your group posting status: Linkedin
Your posts across groups are being moderated temporarily because one of your recent contributions was marked as spam or flagged for not being relevant. Learn more."

May 27
Senator Markey is watching Mike Mulligan...
Transcipts of 2.206
May 21, 2014: Addendum to Palisades Broken Impeller 2.206



Today at 2:11 PM

Salem

“Sheehan said the bolts are about 4 inches long and about 1 inch wide.

Sheehan said one of the main concerns was having the bolt heads damage or stop the impeller at the bottom of the pump which spins and draws the water into the pump in then sends it into the reactor vessel. Also, Sheehan said, there could be the possibility of the impeller, moving at such a high rate of speed, striking and disintegrating a bolt head and sending tiny pieces of metal circulating throughout the cooling system and possibly causing damage.”

Think of the speeds and power he is talking about there: “impeller, moving at such a high rate of speed, striking and disintegrating a bolt head”. There is a lot more weight and metal in the Palisades blade that the bolts and nuts.
Palisades

So the worst Palisades broken impeller blade is 5 inches wide by 12 inches long...by one inch thick.

Despite the application of approximately 3,000 pounds per square inch (psi) of force, the piece did not move. You know the velocity of the water caused that.

Though both IR 2012-03 and the current IR there has been no mention of an equivalent evaluation by Palisades as in Salem's PCP event. The operability of the PCP is a untouchable.

I request the NRC enforce a similar evaluation on the Palisades and I request a OIG inspection on why there is different analysis criteria for similar PCP events between the NRC regions.

Again, I request the Palisades plant be shut down until they replace their PCP with a safer design.

1) How many times did that large Palisades blade spin around in the pump casing before it was spit out? The size of the large broken blade found in Palisades challenges a sheared or frozen impeller accident that severely threatens fuel damage from reduced cooling as mention in Salem and IN 85-03.

2) Certainly the speed of the remaining impellers could shatter a broken blade or pieces and spew small metallic pieces throughout the coolant.

3) Palisades over the years should have carefully documented all the damage to the impellers and evaluated the size of the missing pieces. I am certain many small metallic pieces did get past the flow skirt impeller blade filter, indeed entered the fuel channel and circulated endlessly in the coolant. Why has there been no analysis on this?

4) There is a worry about all these blades pieces found at the bottom of the core upon inspection...there could have been eddies before entering the fuel channel and much erosion throughout the area in all the structures as the material was spinning around in in the under the core flow.

5) The metal blade particles in circulation could have cause erosion of the coolant piping walls throughout the system and also cause flaws in the coolant piping.

6) It certainly looks like larger and larger pieces of blades over time are breaking off the impeller. Has there been an internal evaluation on this?

7) Let’s face facts, in a 30 foot high 4000 hp motor and pump, with a large blade breaking off or more, it could shatter the impeller itself and also the pump casing.

If possible, I would like another chance to speak to the board.  


Sincerely,
Mike Mulligan
Hinsdale, NH

I initiated a NRC process called a 2.206 process on March 17, 2014 over Palisades.
Here is my 2.206 on it.
 
Back in ‘2011” I got on the docket, I predicted, we are going to be shocked with the magnitude of mind blowing Palisades problems in the next few years. I have unnerved many people over the years with my ability to predict future organizational events.
Remember recirculation damage is the explosive collapse of vapor bubbles…it blasts off microscopic metal particles of the impeller and the blades.
May 15:
(It was shortly after the latest turbine trip w/i a day. I don’t know why I can’t come up with the right date. I have talked to numerous inspectors in the last month)
So around May 8 I called up the Salem NRC senior inspector and left a message. He shortly called me back. We talked about the problems with the recent plant trips. He reminded me he knew me from the Vermont Yankee issues. It was like we was old buddies. He was a NRC facilitator at a few of VY contentious community meetings. It was a few meetings past, just after the antis threw cow manure at the NRC inspectors.The NRC had a army of Brattleboro police officers in the meetings and surrounding the high school. There was talk about bringing in the tanks! I talked to this senior resident about the Palisades problems; spoke at length about the meaning of defective PCP impellers. Asked him can you believe the inspectors, said it was safe with the throwing impeller blades all over the place. He didn’t respond. We talked about their brackish service water piping problems...he reminded me they did a rather big piping replacement project.
I just wanted you to know we spent a lot of time talking about Palisades PCP pump problems and I am certain he memorialized the discussion to higher ups.
May 15:
PSEG Nuclear has extended a refueling shutdown of its Salem Unit 2 reactor after discovery of unexplained broken bolt heads in part of the coolant system.
Company spokesman Joe Delmar said Wednesday afternoon that "a conservative decision was made to extend the refueling outage to conduct additional internal inspections of the reactor coolant pumps and make any repairs as needed."
Nuclear Regulatory Commission spokesman Neil Sheehan said the bolt tops are likely from a part of the coolant pump system.
"The concern is that if bolts holding the turning vane failed, the vane could drop and impact the rotating pump internals," Sheehan said.
PSEG operates three reactors at its Artificial Island site along the Delaware River in New Jersey southeast of Port Penn. The company's Salem Unit 1 plant has reported three unplanned shutdowns this year, potentially subjecting the operation to increased oversight.
Why aren't we showing a picture of the actually palisades damaged impeller. They say it only happens in startups and shutdowns. It just  takes a very little amount of time to create this kind of damage.

1) what if two huge chunks of blades come off right next to each other...a seriously unbalanced impeller. Big loca.

2) The blades winging down the piping system with dinging and gouging out piece of the pipe. They are sand blasting the the big primary coolant piping.

3) It is easy design change to fix the impeller in our modern world today.
Cavitation

4) The issue could end up being equal to a locked rotor accident, which has never happened. A locked rotor accident challenges the peak clad temperatures more than any one accident.
Note on the three below pictures, especially with the damaged pump on the floor:
The below picture represents the kind of cavitation damage you might see at the Palisades...these aren't actual Palisades pictures.
Impeller damaged by caviatation

You notice it doesn't happened to one blade...it happens to all of the blades at same time.

Pump Cavitation Damage

The results of a damaged or misbalanced impeller.

Cavitation is a significant cause of wear in some engineering contexts. Collapsing voids that implode near to a metal surface cause cyclic stress through repeated implosion. This results in surface fatigue of the metal causing a type of wear also called "cavitation". The most common examples of this kind of wear are to pump impellers, and bends where a sudden change in the direction of liquid occurs. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation and non-inertial cavitation. 
Inertial cavitation is the process where a void or bubble in a liquid rapidly collapses, producing a shock wave. Inertial cavitation occurs in nature in the strikes of mantis shrimps and pistol shrimps, as well as in the vascular tissues of plants. In man-made objects, it can occur in control valves, pumps, propellers and impellers.
This report indicates a very seriously degraded and dangerous nuclear plant. A big event could pop of of the ether at any moment. They had a heavy lift near miss with the reactor head over "not following procedures" just like ANO.The NRC is also worried about the deteriorating service water system. The NRC documented three failures to follow procedures this period, the SG dam, the bladder getting sucked twice into the suction of the service water system and heavy lift on the reactor head.



05000255/2014002
 

1R20 Outage Activities (71111.20)
a. Inspection Scope
The inspectors evaluated outage activities for a scheduled refueling outage that began on January 19, 2014, and continued through March 18, 2014. The inspectors reviewed activities to ensure that the licensee considered risk in developing, planning, and implementing the outage schedule.
The inspectors observed or reviewed the reactor shutdown and cooldown, outage equipment configuration and risk management, electrical lineups, selected clearances, control and monitoring of decay heat removal, control of containment activities, personnel fatigue management, startup and heatup activities, and identification and resolution of problems associated with the outage.
One of the planned refueling outage activities of particular NRC interest was a foreign object search and retrieval (FOSAR) activity in the reactor vessel. While licensee routinely inspect for foreign material in plant systems and implement controls to prevent the introduction of debris into plant systems, the licensee has in the past identified broken pieces of primary coolant pump (PCP) impellers in the reactor vessel. As a result of a PCP-C vibration transient on October 29, 2011, the licensee suspected a piece of impeller might have broken off and entered the reactor vessel.
Issues with PCP impellers at Palisades date back to 1971 when the impeller for PCP-A was weld-repaired and reinstalled due to damage from foreign material. Below is a timeline of continued issues with PCP impellers.
1983: The licensee identified and removed a piece of broken impeller from under the reactor core barrel during core-offload as part of refueling outage activities. The licensee inspected all of the PCPs and noted the piece originated from PCP-C. The damaged PCP-C impeller was replaced with a new impeller in early 1984.
1984: The newly installed PCP-C impeller failed due to improper assembly and required replacement. The licensee acquired an impeller from another plant, trimmed theimpeller diameter to the proper size, and installed the new impeller.
1999: The site commenced a project to refurbish or replace the four PCPs. The PCP-A impeller was removed for replacement with a spare unused impeller. The removed impeller had cracking on two of the five vanes that was attributed to inadequate post-weld heat treatment in 1971, and the impeller was weld-repaired for future use.
2001: The weld-repaired impeller from PCP-A was installed in PCP-B. This was the first impeller replacement for PCP-B and the removed impeller had cracking in three of the five vanes. The removed impeller was weld-repaired for future use.

2003: The licensee removed the trimmed impeller from PCP-C for replacement and noted extensive damage such that repair was not viable. The impeller was replaced with the refurbished impeller that had been removed from PCP-B.

2007: The licensee identified and removed two impeller pieces from the reactor vessel.

2009: The original impeller in PCP-D was removed and replaced with a newly manufactured impeller. The original impeller was subsequently inspected and found to have recirculation damage, but no cracking.

2014: The licensee removed the impeller from PCP-C and replaced it with a newly manufactured impeller. The removed impeller had missing portions in two impeller vanes.

The 2014 refueling outage included the removal of the core barrel to support more comprehensive reactor vessel inspections than can typically be conducted. This activity was pre-planned for reasons not related to the pump impeller concern, but coincidentally allowed for a more thorough inspection for foreign material in the reactor vessel. The licensee anticipated finding the suspected broken piece from the PCP-C vibration event in October 2011 in the vessel. The reactor vessel FOSAR activities identified two pieces of broken impeller; one piece was removed from the vessel and the other piece was lodged between the reactor vessel and the bottom corner of the flow skirt. The licensee attempted to remove the lodged piece using several methodologies, including pulling using vice grips and pushing using hydraulic tools. Despite the application of approximately 3,000 pounds per square inch (psi) of force, the piece did not move.
The reactor vessel is shown in the figures below. Four PCPs circulate water through the PCS. After the water has passed through the steam generators and transferred heat to the secondary system, the water is pumped by the PCPs through the PCS cold legs and into the reactor vessel. In the included figures that depict the Palisades PCS, one cold leg (inlet nozzle) and one hot leg (outlet nozzle) are shown for the purpose of simplicity. In actuality, there are four cold legs and two hot legs. Water enters the reactor vessel via the cold legs and flows down between the reactor vessel wall and the core support barrel. Near the bottom of the vessel is a flow skirt that contains many small holes that most of the water flows through. Some water also passes below the flow skirt into the bottom of the vessel. After flowing through or under the flow skirt, the water then flows up into the active fuel region to remove heat from the nuclear fuel. After flowing through the fuel region, the water exits the vessel through the hot legs and into the steam generators.


Since the licensee could not remove the impeller piece from the vessel, Operability Evaluation CR-PLP-2014-01510 was developed to evaluate the operability of the reactor vessel. The piece was tapered in thickness from 3/16 inches to roughly one inch wide, and the gap between the vessel wall and flow skirt where the piece was wedged was up to ½ inch wide. The piece was not blocking any of the flow holes through the flow skirt. Plant history has shown that prior broken impeller pieces that passed through the gap were found at the bottom of the vessel. The licensee performed a fluid dynamics analysis to determine the forces that would act on the piece during plant operation, which concluded that the maximum force would be a 350 pound lift force. The site then performed a structural analysis to determine the effects of the piece and hydraulic forces on the reactor vessel and flow skirt. Heatup and cooldown effects were considered and the flow skirt and vessel were determined to move together such that the gap size would remain constant. A fracture analysis was performed to determine if the piece would break up into smaller pieces during the operating cycle. The analysis assumed several initiating crack sizes in the piece, all of which determined that the crack growth rate would reduce and essentially stop once the crack depth approached 75 percent of the thickness of the piece. Based on the results of the analyses, the licensee concluded that the piece would not move, would not break up, would not impede PCS flow, and would not affect the pressure-retaining capability of the reactor vessel. The analyses were performed as a joint effort between the licensee and equipment vendors. The licensee’s Operability Evaluation concluded the reactor vessel was operable with the impeller piece wedged between the reactor vessel and the flow skirt.
The licensee concluded that the cause of the repeated impeller failures was fatigue-related effects from the operation of the PCPs in conditions beyond the maximum flow rate and below the minimum net positive suction head recommendations as described in design documentation. These conditions are present when operating only one or two PCPs (one on each loop) during reduced temperatures and pressures (i.e., during startup and shutdown activities). Cyclic pressure pulses and stresses are created under these reduced pressure conditions that act on the leading edges of the impellers, which can ultimately lead to impeller vane cracking and the break-off of small impeller pieces. The licensee determined, based on metallurgical examination of a previous impeller piece that broke off and the mechanism by which the cracks propagated, that weld refurbished impellers were particularly susceptible to degradation. At normal operating temperature and pressure, there is adequate net positive suction head on all PCPs, so these additional stresses are not present.
The inspectors and NRC staff from headquarters conducted an in-depth independent review of the analyses forming the basis for the licensee’s conclusions. The independent review included:
• The licensee’s analytical basis for why the wedged impeller fragment was expected to remain in place;
• The licensee’s determination that the impact of the impeller fragment wedged between the reactor vessel and the flow skirt did not exceed the structural integrity of the vessel wall or the flow skirt support welds;
• The licensee’s analysis for why the wedged impeller fragment was not expected to break into smaller pieces and in the unlikely scenario that it did, the impact of the pieces on fuel cooling, fuel cladding, and the reactor vessel structure;
• The licensee’s assessment of the potential for corrosion at the interface of the wedged impeller fragment, reactor vessel, and flow skirt; and
• The licensee’s assessment of a worst case scenario accident that could result in the impeller piece impacting the reactor vessel or affecting fuel integrity

Pilgrim Still Going Crazy On Us.




May 15

Told you it was a recirc pump...
Neil Sheehan, a spokesman for the Nuclear Regulatory Commission, said the work includes installation of a new recirculation pump seal, repairs to valves in the feedwater system, and replacement of a leaking component in the system that takes water from the bay and uses it for plant cooling.
Crap service water piping needing a total replacement.
Leak in SSW piping downstream from RBCCW Heat Exchanger ‘B’ on February 24 
Junk new CRD pump?

Control rod drive ‘A’ pump oil leak on February.

B’ control rod drive (CRD) prior to ‘A’ CRD pump replacement on December 2

ATTACHMENT 3

TO ENTERGY LETTER 2.14.032

PILGRIM RELIEF REQUEST PRR-25, Re

Calculation Cover Page EC # 49514

Pilgrim Salt Service Water Discharge Piping Elbow (JF29-8-4) Wall Thinning Stress

AnalysisStructural Integrity Associates Calculation No. 1400287.301, Rev. 0
(22 Pages)
Remember shutdowns damages safety equipment. Barely six months from the last shutdown and they have all these problems. Nobody knows how long these things were simmering and are they really safety related.

My bet it is the recirc pump seals...
Maintenance will be done on piping, valves, pump seals and electrical equipment
 Pilgrim Coalition
Summary of Shutdowns & Glitches in 2013:

·         January 10-17: Both recirculation pumps tripped, followed by a head drain valve leak.
·         January 20-24: Leaking safety valve.
·         February 8-16: Winter storm causes offsite power loss and main generator load reject; 169 hours down.
·         April 18 – June 3: Scheduled refueling.
·         August 22-26: Electrical problems cause all three main water pumps shut down.
(Plant restarts on August 26, but does not reach full power before…)
·         September 8-17: Steam pipe leak.
·         Oct. 14-21: Off-site power to plant unavailable because of NStar problem, which caused initial shutdown. Plant remained closed for two days after power restored because of faulty mechanical pressure regulator, which caused water levels in the nuclear reactor to become too high.
·         December 4: Leaky steam valve. Reactor still down.
Pilgrim powering down for planned repairs

By CHRISTINE LEGERE

clegere@capecodonline.com

May 13, 2014
PLYMOUTH – Pilgrim Nuclear Power Station officials are powering down the reactor to do some repairs, a spokesman for the plant announced tonight.
“After careful consideration we made the conservative decision to take Pilgrim off-line to perform necessary maintenance to address low-level equipment needs that could potentially challenge reliability for the remainder of the operating cycle,” spokeswoman Joyce McMahon said in an email. The timing of the outage had been planned in advance after a discussion with grid operator ISO-New England.
 “Pilgrim’s power is vital to the grid,” McMahon said. “ISO-NE asked us to schedule maintenance at this time so Pilgrim can provide power during other power plants’ scheduled maintenance outages as well as during the coming peak summer demand.”
Maintenance will be done on piping, valves, pump seals and electrical equipment. “This maintenance will directly support increased reliability for the rest of our operating cycle, which ends with the next scheduled refueling in mid-2015,” McMahon said

 

 

Tuesday, May 13, 2014

ANO: Least They didn't Kill Anyone This Time

ARKANSAS NUCLEAR ONE – NRC INTEGRATED INSPECTION REPORT 05000313/2014002 AND 05000368/2014002

Green. Inspectors documented a self-revealing finding for the licensee’s failure to correctly install the flexible link bolted connection on phase C of the 6.9 kV non-segregated bus of the Unit 2 auxiliary transformer, which contributed to the explosion of the Unit 2 auxiliary transformer. The licensee documented the issue in Condition Report CR-ANO-2-2013-02242. The licensee aligned startup transformer 3 (preferred offsite power source) to carry the plant loads during normal power operations and restarted the plant on January 10, 2014. The transformer is scheduled to be replaced during the upcoming refueling outage starting in May.

• Green. Inspectors documented a self-revealing finding for the licensee’s failure to correctly land the signal wire from the Unit 2 auxiliary transformer differential relay output contacts to the main generator lockout relay, which contributed to the explosion of the Unit 2 auxiliary transformer. The licensee documented the issue in Condition Report CR-ANO-2-2013-02242. The licensee correctly landed the wire and aligned startup transformer 3 (preferred offsite power source) to carry the

• Green. The inspectors reviewed a self-revealing non-cited violation of 10 CFR 50.63, “Loss of all alternating current power,” for the licensee’s failure to maintain the alternate ac diesel generator as a power source available to withstand and recover from a station blackout. Specifically, the licensee failed to perform preventive maintenance on the governors of the diesel in accordance with the recommended vendor maintenance, which resulted in an overspeed trip of the engine during testing. The licensee repaired the governors