ML19257D704
| ML19257D704 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 01/31/1980 |
| From: | Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | Harold Denton, Parr O Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0660, RTR-NUREG-660 N1F-S8.14-1, NUDOCS 8002050491 | |
| Download: ML19257D704 (38) | |
Text
__ _-
VruotNrA ELucrutcAND POWER C O ktI% N Y lltetr3 on o,VIILOIN IA 20261 January 31, 1980 Mr. Harold R. Denton, Director Serial No. 1161/121879 Office of Nuclear Reactor Regulation LQA/ESG: dbs Attn: Mr. O. D. Parr, Chief Light Water Reactors Branch No. 3 Docket No. 50-339 Division of Project Management U. S. Nuclear Regulatory Commission Washington, D.C. 20555
Dear Mr. Denton:
IMPLEMENTATION OF THE RECOMMENDATIONS OF NUREC-0660 ENHANCEMENT OF ONSITE EMERGENCY DIESEL CENERATOR RELIABILITY NORTH ANNA UNIT 2 We have received and reviewed Mr. Parr's letter of December 18, 1979, which requested our responses to specific recommendations of NUREG-0660.
The requested information is attached.
Please contact us should you require additional information concerning these responses.
Very truly yours,
~.
C. M. Stallings Vice President - l'ower Supply and Production Operations Attachment i876~1.06 800f?050 49/
7.Y
N1F S8.14-1 CO:MNT 8.14 Provide a discussion of the measures that have been taken in the design of the standby diesel generator air starting system to preclude the fouling of the air start valve or filter with moisture and contaminants such as oil carryover and rust. (9.5.6, Part Ill, item 1).
RESPOSSE Each Emergency Diesel Generator is supplied with a complete starting air system with compressor, air reservoirs, air dryers, relief valves, dual starting air solenoid valves, pressure switches and gauges, etc. The individual systems are interconnected to provide an overlap of air pressure in case of any piece of equipment being inoperable. Th air compressors are Quincy two stage units, cach having the loadless start features, and are driven by electric motors. ".he air reservoirs are connected through valves to a common manifold which allows either or both reservoirs to supply the air start solenoid valves for starting the engine. This arrangement provides redundancy in the air start system. A water separator downstream of the compressor af ter-cooler is installed to remove moisture accumulation along with refrigerant air dryers. Additionally, a pre-filter is installed to remove particulate and oil mist carried in the compressed air stream.
1876'i07
NLF S8.15-1 COMMENT 8.15 Experience at some operating plants has shown that diesel engines have f ailed to start due to accumulation of dust and other deliterious material on electrical equipment associated with starting of the diesel generators (e.g.,
auxiliary relay contacts, control switches - etc.).
Describe the provisions that have been made in your diesel generator building design, electrical starting system, and combustion air and ventilation air intake design (s) to preclude this condition to assure availability of the diesel generator on demand Also describe under normal plant operation what procedure (s) will be used to minimire accumulation of dust in the diesel generator room; specifically address concrete dust control.
In your response also consider the condition when Unit 1 is in operation and Unit 2 is under construction (abnormal generation of dust) .
RESPONSE
Inlet louver dampers along with an aluminum bird screen are used at the combined ventilation and combustion air inlet wall. This prevents the introduction of deliterious material to the emergency diesel generator space. Air filters are provided in the combustion inlet air ducting to prevent dust infiltration into the engine.
All of the diesel generator control cubicles in the diesel generator room are equipped with fully gasketed doors. The cubicle which houses the excita-tien transformer has unfiltered louvers in the rear for heat removal. However, all interconnecting cables which penetrate the excitation transformer cubicle from the other control cubicles are fully gasketed. There are other controls for the diesel generator which are located in the emergency switchgear room, the main control room, and the normal switchgear room. Since these areas are ventilated with air conditioned air, and there is little or no dust generated, these areas pose no concern for the dust problem.
1876 108 4
N1F S8.15-2 A description of the diesel ventilation system is presented in Connent S9.93 of the FSAR. A diagram of Diesel Cubicle Ventilation, N1F Fig.
S9.93-1, is provided. This diagram depicts the path of outside air as it enters and exits the diesel generator room while the diesel is in operation.
The surface of the ground outside the air intake has been graded with crushed stone. The crushed stone has-limited the generation of dust in the diesel generator room.
Unit 2 has been completed so that it does not generate any dust from construction.
Logs are taken every four hours by operations personnel in the diesel genera-tor rooms. 'n'hile it has always been general policy for operations personnel to note any area of the plant which needs cleaning and initiate corrective a c t io n, a note has been added to the diesel generator room logs which will instruct the operator to issue a work order to clean the diesel generator room if it is so required.
i876 109,
N1F 58.16-1 COMMENT 8.16 The diesel generators are required to start automatically on loss of all of f site power and in the event o f a LOCA.
The diesel generator sets should be capable of operation at less than full load for extended periods without degradation of performance or reliability. Should a LOCA occur with availability of of fsite power, discuss the design provisions and other parameters that have been considered in the selection of the diesel generators to enable them to run unloaded (on standby) for extended periods without degradation of engine performance or reliability. Expand your PSAR/FSAR to include and explicitly define the capability of your design with regard to this requirement. (SRP 9.5.5, Part III, Item 7).
RESPONSE
The manufacturer (Fairbanks !brse, Inc.) of the North Anna #2 Emergency Diesel Generators states the following with respect to No-Load operation:
"There are no techanical limitations on running the Model 38TDS-1/8 engine at full speed no load conditions; however, running in an unloaded con-dition will result in an accumulation of unburned oil residue in the engine exhaust system. If, under this condition, a sudden load were applied, it could result in a " stack" fire. Therefore, it is recommended that the engine be loaded up to 50-75 percent rated continuous load for one hour af ter any 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period of unloaded operation."
Operating procedures will be modified to insure that the engine is loaded up prior to securing the unit, after extended no-load operation.
i876 110
N1F S8.17-1 COMMENT 8.17 Section 9.5.4.1 caergency diesel engine fuel oil storage and transfer system (EDEFSS) does not specifically reference ANSI Standard N195 " Fuel Oil Systems for Standby Diesel Generators". Indicate if you intend to comply with this standary in your design of the EDEFSS; otherwise provide justification for non-compliance. (SRP 9.5.4, Rev. 1, Part II, item 12).
RESPONSE
The construction permit for North Anna Unit #2 was granted in February 1971, therefore, compliance with an ANSI standard issued in April 1976 is not considered appropriate. However, N.A. Unit 2 Emergency Diesel Generators do comply with ANSI N195-1976 with the following exceptions:
- 1. Paragraph 6.1 Tank _s, The overflow line from the day tank is to the ground and not to the supply tank.
- 2. Paragraph 6.3 Strainer In place of a strainer and engine fuel filter a duplex fuel oil filter is provided for each engine.
- 3. Paragraph 7.5 Other Requirements A fill line duplex strainer is provided for N.A. Unit Nos. 1&2 Fuel Oil Tank (5000 BBL capacity). This tank then supplies the Emergency Diesel Generator underground Fuel Oil Storage Tanks.
No strainer is provided between these fuel oil tanks.
1876 111
NIF S8.18-1 COMMENT 8.18 Assume an unlikely event has occured requiring operation of a diesel generator for a prolonged period that would require replenishment of fuel oil without interrupting operation of the diesel generator. What provision will be made in the design of the fuel oil storage fill systaa to minimize the creation of turbulence of the sediment in the bottom of the storage tank. Stirring of this sediment during addition of new fuel has the potential of causing the overall quality of the fuel to become unacceptable and could potentially lead to the degradation or failure o r the diese1 generator.
RESPONSE
No special provision is made in the design of the fuel oil storage fill system to minimize the creation of turbulence of the sediment in the bottom of the storage tank. However, the fuel oil suction line from the underground storage tanks is six inches above the bottom of the tank, also, a strainer and foot valve are provided in each Emergency Generator Day Tank (1000 gallon capacity).
i876 112.
N1F S8.19-1 COMMENT 8.19 Discuss the precautionary measures that will be taken to assure the quality and reliability of the fuel oil supply for emergency diesel generator operation. Include the type of fuel oil, impurity and quality limitations as well as diesel index number or its equivalent, cloud point, entrained moisture, sulfur, particulates and other deliterious insoluble substances; procedure for testing newly delivered fuel, periodic sampling and testing of on-site fuel oil (including interval between tests), interval of time between periodic removal of condensate from fuel tanks and periodic system inspection. In your discussion include reference to industry (or other) standard which will be followed to assure a reliable fuel oil supply to the emergency generators. (SRP 9.5.4, Part III, items 3 and 4).
RESPONSE
A description of the fuel oil specifications is presented in Comment S9.101 of the FSAR. The vendor which is presently used to supply fuel oil is contracted to supply oil with the following specifications:
TYPICAL SPECIFICATIONS NO. 2 FUEL OIL Gravity API 35 (Maximum of 40)
Viscosity, SUS 0 100 E 33 Flash 150 F (140 F Minimum)
Pour -20 F (O F Maximum)
Sulfur 0.18% (0.50% Maximum)
Vanadium Less than 0.5 PPM bbgnesium Less than 0.5 PPM Nickel "il Lead Nil Bru's per gallon 139,400 1876 113
NiF S8.19-2 No testing of fuel oil is performed on newly delivered fuel prior to entering the above ground storage tank.
Periodic sampling of the above ground tank, each underground tank, and each day tank is accomplished in accordance with Unit 2 Proof and Review Technical Specification 4.8.1.1.2.b. This sampling is required at least once per 92 days by verifying that a sample of diesel fuel from the fuel storage tank obtained as a DRAIN Sample in accordance with ASTM-D270-65, is within the acceptable limits specified in Table 1 of ASTM D975-74 when checked for viscosity, water and sediment.
The underground tanks and the day tanks are generally maintained full at all times. This limits the formation of condensate from any air vapor in the tank. The fuel oil storage tanks are checked every 92 days for condensation and are cleaned out as required. To date this has not been required.
i876 114
N1F S8.2CF1 COMMENT 8.20 Operating experience has shown that accumulation of water in the starting air system has been one of che most f requent causes of diesel engine failure to start on demand. Condensation of entrained moisture in com-pressed air lines leading to control and starting air valves, air start motors, and condensation of moisture on the working surfaces of these components has caused rust, scale and water itself to build up and score and jam the internal working parts of these sital components thereby preventing starting of the diesel generators.
In the event of loss of offsite power the diesel generacors
-__ _. _ . . . . . _ _ _ . must function sinca they are vital to the safe shutdown of the reactor (s). Failure of the diesel engines to start from the effects of moisture condensation in air starting systems and from other causes have lowered their operational reliability to substantially less than the desired reliability of 0 .99 as specified in Branch Technical Position ICSB (PSB) 2 " Diesel Generator Reliability Testing" and Regulatory Guide 1.108 " Periodic Testing of Diesel Generator Units Used as Onsite Electric Power Systems at Nuclear Power Plants."
In an effort toward improving diesel engine starting reliability NUREG-0660 indicates that compressed air starting system designs include air dryers for the removal of entrained moisture. The two air dryers most commonly used are the dessicant and ref rigerant types. Of these two types, the refrigerant type is the one most suited for this application and therefore is preferred. Starting air should be dried to a dew point of not more than 50 F when installed in a normally controlled 70 F environment, otherwise the starting air dew point should be controlled to at least 10 F less than the lowest expected ambient temperature.
Describe your diesel engine air starting system and indicate how your system meets the recommendation stated in NUREG-0660.
If there are any differences between your design and the recommendations of NUREG-0660, provide justification for your design cr plans for implementation.
RESPONSE
1876'l15.
The air starting system consists of the starting air piping and the en-gine starting mechanism. Air for the starting system is required at between 150 and 250 psi at the engine and is scored in air storage tanks. Engine starting is accomplished by the action of compressed air on the pistons in their proper firing order. The engine starting mechanism includes the air start control valve, air start distributor, the air header, the pilot air
N1F S8.20-2 tubing and the air start check valves at the individual cylinders. Regrig-erated starting air drye_ s are provided between the air compressors and the air storage tanks as recommended by NUREG-CR-0660.
i876 'l16
N1F S8.21-1 COMMENT 8.21 Operating experience at certain nuclear power plants which have two cycle turbocharged diesel engines manufactured by the Electromotive Division (EMD) of General Motors driving emergency generators have experienced a significant number of turbocharger mechanical gear drive failures. The failures have occurred as the result of running the emergency diesel generators at no load or light load conditions for extended periods. No load or light load operation could occur during periodic equipment testing or during accident conditions with availability of offsite power.
When this equipment is operated under no load conditions insufficient exhaust gas volume is generated to operate the turbocharger. As a result the turbocharger is driven mechanically from a gear drive in order to supply enough combusion air to the engine to maintain rated speed. The turbocharger and mechanical drive gear normally supplied with these engines are not designed for standby service encountered in nuclear power plant application where the equipment may be called upon to operate at no load or light load condition and full rated speed for a prolonged period. The EMD equipment was originally designed for locomotive service where no load speeds for the engine and generator are much lower than full load speeds. The locomotive turbocharged diesel hardly ever runs at full speed except at full load. The EMD has strongly recommended to users of this diesel engine design against operation at no load or light load conditions at full rated speed for extended periods because of the short life expectancy of the turbocharger mechanical gear drive unit normally furnished. No load or light load operation also causes general detericration in any diesel engine.
To cope with the severe service the equipment is normally subjected to and in the interest of reducing failures and increasing the availability of their equipment EMD has developed a heavy duty turbocharger drive gear unit that can replace existing equipment. This is available as a replacement kit, or engines can be ordered with the heavy duty turbocharger drive gear assembly.
To assure optimum availability of emergency diesel generators on demand, Applicant's who have on order or intend to order emergency generators driven by two cycle diesel engines manufactured by EMD should be provided with the heavy duty turbocharger mechanical drive gear assembly as recommended by EMD for the class of service encountered in nuclear power plants. Confirm your compliance.with this requirement.
18L76 ,
117
i .
RESPONSE
North Anna Unit #2 Emergency Diesel Generators were manufactured by Fairbanks Morse, Inc. (Colt Industries), and therefore, E}ID's turbocharger problem is not applicable.
1876 118,
\
N1F S8.22-1 COMMENT 8.22 Provide a detail discussion (or plan) of the level of training proposed for your operators, maintenance crew, quality assurance, and supervisory personnel responsible for the operation and maintenance of the emergency diesel ge ne ra to rs . Identify the number and type of personnel that will be dedicated to the operations and maintenance of the emergency diesel generators and the number and type that will be assigned f rom your general plant operations and maintenance groups to assist when needed.
In your discussion identify the amount and kind of training that will be received by each of the above categories and
_ _ _ _ _ _ _ _ _ .the _ type _of ongoing training program planned to assure optimum availability of the emergency generators.
Also discuss the level of education and minimum experience requirements for the various categories of operations and maintenance personnel associated with the emergency diesel generators.
RESPONSE
TRAINING OF OPERATIONS PERSONNEL North Anna Operators are provided with training on the emergency diesels in three (3) programs: 1) Operator Development Program; 2) Operator License Program; 3) Operator Requalification Program.
There are 13 licensed operators and 18 non-licensed operators who are qualified to operate the diesel generator units. The 18 non-licensed operators have demonstrated proficiency in the operation of the diesels by completing the diesel generator qualification program-There are 13 senior reactor operators assigned to operations as super-visory personnel that are qualified to operate the diesel.
The Operator Development Program uses a combinatien of self-study, practical demonstra tion and writ ten examinatione to accomplish the desired training. A description of this training as it applies to the emergency diesels is attached.
1876 ,
Ii9
N1F S8.22-2 TRAINING ON EMERGENCY DIESELS FOR OPERATOR LICENSE PROGRAM TOPICS COVERED BY LECTURE DURING OPERATOR LICENSE PROGRM1 ON THE EMERGENCY DIESELS (4 HOUR LECTURE)
- 1. Purpose of system and design criteria.
- 2. General description of the engine.
- 3. Start sequence, signals and reasons.
A. Exercise start B. Emergency start C. Local start /CRE
- 5. Function of all switches and controls. Including the effect on operability and start sequences.
- 6. Generator and electrical controls and interlocks.
- 7. Shutdown featurea, setpoints and reasons.
A. Emergency shutdown B. Normal sb ;tdowns C. Reset and interlocks associated with shutdown features
- 8. Loading sequence on loss of voltage.
A. Degraded Voltage Protection B. With Safety Injection C. With Containment Depressurization Actuation D. Output and supply breaker interlocks
- 9. Technical specifications for emergency diesels.
A. Unit 1
- 3. Unit 2 1876~120
N1F S8.22-3 Additional training on Emergency Diesels during Operator License Program is included in some aspects of the following:
- 1. Lecture on Fuel Oil System.
- 2. Lecture on Fire Protection.
- 3. On-Shif t Qualification Card for RO and GRO License Training Requires:
A. Perform or simulate 1-PT-82A or 823. (Diesel start / surveillance checks.)
B. Simulated actions for:
- 1. Station Blackout
- 2. Loss of D Transfer Bus
- 3. Loss of E Transfer Bus
- 4. Loss of F Transfer Bus
- 5. Safety Injection
- 4. Trainees are continually examined on the Emergency Diesels during license training, on their final audit examination, audit oral examinations and during the NRC examinations.
1876 .121
N1F S8.22-4 DESCRIPTION OF TRAINING ON ESIERGENCY DIESELS FOR OPERATOR REQUALIFICATION PROGRAM The 1979 Operator Requalification Program included the following training on Emergency Diesels:
- 1. Lecture on Degraded Voltage Protection (1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />).
- 2. Simulator training on the following malfunctions:
A. Loss of vital power B. LOCA's C. Main Steam Line Breaks D. Steam Generator Tube Rupture E. Station Blackout
- 3. Each licensee is expected to document diesel engine starts in the training log.
t
TRAINING OF ELECTRICAL MAINTENANCE PERSONNEL At present no specific number or type of electrical maintenance personnel are dedicated to maintaining the emergency diesel generators. Electrical maintenance personnel receive general electrical training in an 11 step program based on experience and written tests. Electricians receive no specific training concerning maintenance of the emergency diesel generators.
Normal prevention maintenance consisting of test measurements, general inspection, and cleaning of the emergency diesel generator is performed by the electricians. Normal one or two senior electricians, 9 steps or above, and one journeyman electrican are assigned to electrical maintenance work on the emergency diesel generator. Any electrical maintenance other than minor external repairs is normally performed under the direction of the manufacturers representative. At present, no specific emergency diesel electrical maintenance training program is planned. Most electricians have graducated from high school or have passed CED examinations.
TRAINING OF MECHANICAL MAINTENANCE PERSONNEL At present no specific number or type of mechanical maintenance personnel are dedicated to maintaining the emergency diesel generators. Mechanical maintenance personnel are trained as general mechanics and receive no specific training concerning maintenance of the emergency diesel generators. Mechanics are trained in a twelve step program. Mechanics are promoted from one step to another based on experience and written tests. Normally two senior mechanics, 9 steps or above, and one lower level mechanic are assigned to trouble shoot the diesel. Any mechanical maintenance which is performed on the diesel is normally performed under the direction of the manufacturers representative except for routine maintenance replacement and/or adjustments to minor parts. At present no specific emergency diesel generator mechanical maintenanc 187i6 123
i -
training program is planned. Most mechanics have graduated from high school or have passed a GED examination.
TRAINING OF QUALITY CONTROL PERSONNEL At present no specific number or type of quality control personnel are dedicated to maintaining-the emergency diesel generators. Quality -
control personnel receive general on the job training to read codes and specifications and are familiar with maintenance procedures. All QC personnel have graducated from high school or passed CED examinations and many hold college degrees. The on site Quality Control Engineer and a member of the on site QC staff received speake U.S. Navy training on diesels of the same class as those used at North Anna. No rmally major repairs to the emergency generators are given full coverage by QC and usually one shift of the coverage is provided by the on site QC staff member with the applicable U.S. Navy training mentioned above. Minor repairs to the diesel generators are subj ect to and often are spot checked on site QC, An on site in house QC general training program which includes specific training on the emergency diesel generators was recently formulated and is now in progress.
1876,124
DESCRIPTION OF TRAINIf4G ON EMERGENCY DIESELS FOR OPERATOR DEVELOPMENT PROGRAM 1876 125
NF S8.22-8 QUALIFICATION RECORD s,
!IAME: PAGE 2 of 9 SYS" "~~""- Rrv
- N' o * /
(1 TYP. ENGINE / GEN. SYST.)
l intI: :;o . I and 2 DArr: 1i/03/78 REQUIRE.'C.T DirrIAL 1.0 En.ine .
1.1 Model .'.
1.2 Type .
13 Specifications 1 3.1 No. Cylinders / RPM 132 H.P./K.V. Ratings ,
N 1.4 Comconents 1.4.1 Gove rno r 1.4.1.1 Type / Location 1.4.1.2 Controls 1.4.1.3 . Linkage to fuel rack 1.4.1.4 OperationOil/ jLevels [ Type 1.4.2 _Tu rbocha rce rs 1.4.2.1 Loca tion / Purpose
. 1.4.2.2 Operation 1.4.2 3 Cooling / Lubrication o 1.4.3 Crankcase E_iector Assy.
1.4.3.1 Location / Purpose 1.4.3.2 ~ Opera tion 1.4.4 Scavance Air Blower 1.4.4.1 Location / Purpose }h[b }2b 1.4.4.2 Operation
~NIF S8.22-9 QUALIFICATION RECORD ^ .
PAGI' 3 of a NA.E :
EMEP,GE! ICY DIESEL GEN. SYSTEM RI"/ . ,.O
.. . /
SYS m *
(1 TYP. EtiGitiE/ GEN. SYST.)
DATE:: 11/03/78 t; NIT No. I and 2 INITI?J RIgcI?r.:e:.T .
1.5 systems Fuel Cil Trans fer> System .,
15.I 1.5.1.1 Transfer Pumps (L-EG-P-1-A/B) location / Power Source; Cpera tion 1.5.1.2 50,000 gal . underground tank 1.5.1.3 Day Tank .
1.5.2 Encine Fuel System
'N 1.5.2.1 Engine Driven Fuel Pump; Location / Operation 1.5 2.2 Aux. Fuel Pump (1-EG-P-01) location / Power Source; Operation.
1.5.2.3 Duplex Fil ters ; Locaticn/ Purpose 1.5.2.4 injection Pumps; Lecation/ number / Operation Connection linkage to governor.
Injection Nozzle: Location / Operation 1.5.2.5 Number per cylinder.
1.5.3 Encine Coolant System
- 1. 5. 3.'l Stand by ccolant pump (L-EG-P-03) location / Power Source; Operation; Coolant drain tank line-up.
1.5 3 2 Jacket Wa ter Heater (1-EG-HT .1)
- Location /Pewer Source; Opera tion-1.5 3 3 Stand-by Heat Exchanger ,
L c c.' t i o n / P u -~, s a
N1F S8.22-10 QUALIFICATION RECORD
\ PAGI h of 9 u
l' v.S :
ggy, 3g, 7 EMERGENCY DIESEL CEN. SYSTEM SY S ^~""r'4 - SYST.)
(1 TYP. ENGINE / GEN. l DATI: 11/03/78 UNIT no. I and 2 INI"'IAL -
F2QUIPCCIT 1.5.3 4 Engine Drive Coolant Pump . . .
Loc & tion / Operation I.5.3 5 TCV; Location / Purpose; Operation I.5 3 6 Radiators 1.5 3 7 Lube Oil Cooler Expansion Tank:
Location; Level Indication 1.5 3.8 s Chem. Treatment; Filling / Draining System Cooling Fan: Gear Box / Drive System; 1.5 3 9 Ai r inlet / Discharge Ficw 1.5.4 Encine Lube System _
l.5.4.1 Engine Driven Lube Oil Pump Location / Operation 1.5 4.2 L.O. Filter Location / Type; internal By-Pass Valves
. 1.5.4.3 L.O. Cooler Location / Type; Cooling Medium 1.5.4.4 L.O. Strainer Cleaning Location / Type / Purpose; Pre-Lube Pump (1-EG-P-02) 1.5.4.5 Location / Purpose; Operation (Man / Auto) 1876 128
N1F S8.22-11 OUALIFICATION RECORD m
N A ". : PAcz 5 of 9 EME?.GENCY DIESEL GEN. SYSTEM SYs LM: RT/. NO. /
(1 TYPE. ENGINE / GEN. SYST.)
C:C : :;0. I and 2 DAS :: 11/03/73
- RIITIAI, REQUIFL_
1.5.4.6 L.o. Circulation System .
Pump (OPM); 3-Way Valve; Stand-By Hea t Exch.
Lube Oil Fill Connection; Operation.
1.6 Startino Ai r Svstem 1.6.1 Ai r Cercressors (1-EG-C-I A/S) 1.6.1.1 Type / Operating Pressure .
'N ,
1.6.1.2 Elec. Motor Power Source; Cperation
.1.6.1.3 Diesel Engine Operation; Bel t Re-alignment 1.6.2 air O rve rs _
1.6.2.1 Type 1.6.2.2 Operation 1.6.3 Ai r Receivers
. 1.6.3.1 Relief Valves 1.6.3 2 Volume (Number of ~ starts)
, 1.6.4 Solenoid Valves (AS-1 & AS-2) 1.6.4.1 Location / Purpose 1.6.4.2 Vent Valve (AV)
~
1.6.5 . Ai r S ta rt Di s t ri bu to r i876 129'
NIF S8.22-12 OUALIFICATION RECORD ,
NA.E: PAGE 6 of 9 EMERGENCY DIESEL GEN. SYSTEM R4V. NO . /
SY S ~'-r" -
(1 T(P. ENGINE / GEN. SYST.)
UNIT no. I and 2 DATE: 11/03/78 REQUIP 5_:C r . INITIAL 1.7 !nstrumentation/ Controls / Alarms
~
1.7.1 Encine ,
l.7.1.1 Overspeed Trip Mechanism 1.7.1.2 Local Control Panei Controls 1.7.1.3 Crankcase Press.
1.7.1.4 Enginc Operating Modes
~
N Auto Remote, Man. Remote; Man. Local
~
1.7.1.5 Covernor Control Syst.
Normal opns. ; Shutdown SOV action 171.6 Auto Shutdown Features l .7.2 _ Fuel Oil Trans fe r Sys tem 1.7.2.1 Level Control / Indica tions 1.7 2.2 Local Control Panel Controls 1.7.3 Encine Fuel System
. 1 7 3.1 Press./ Temp.
1.7 3.2 Indication / Alarms 1.7.3 3 Local Control Panel Controls 1.7.4 Encine Coolant System 1.7.4.1 Press./ Temp.
1.7.4.2 Indications / Alarms i876 130 1.7.4.3 Local Control Panel Controls
e .. -
QUALIFICATION RECORD .
PACI 7 of 9 NA.E:
pyy , no, /
EMERGENCY DIESEL GEN. SYSTEM SYSTIM:
(1 TYP. EN0lNE/ GEN. SYST.)
l DATE: 11/03/73 UNIT No. I and 2 INITIAL ,
REQUIPSC.'"'
~
1.7 5 Encine tube System. _
l.7.5.1 Press./ Temp.
1.7 5 2 indi ca tions/Ala rms 1.7 5 3 Local Control Panel Controls 1.7.6 Startina Air System 1.7.6.1 Press. Control (s)
"N 1.7.6.2 Alarms l
1.7.7 Start circuits I and 2 1.7.8 Auto. Encine Shutdown 2.0 Gene ra tor 2.1 Tvoe/Ra ti ngs 2.2 _Lubricaticn (Bearings) 2.2.1 Level .ndication 2.3 P ro tec t i on (Relaying) 2.3 1 Phase Differential (87) 2.3 1.1 Loca tion 2.3.1.2 Trip Actions Gen. Output Breaker; Emerg. Engine Stop 2.3.1.3 Light I ndi ca t i on 2.3 2 Phase Overcurrent 2.3.2.1 Trip Action (Skr) 1876 131 *
.2.3.2.2 Location
N1F S8.22-14 QUALIFICATION RECORD
's PAGE 8 of 9 NAME:
EMERGENCY DIESEL GEN. SYSTEM
- C' I (I TYP. ENGINE / GEN. SYST.)
I UNIT ::0. I and 2 DATE: 11/03/78
~ INITI.M.
PIQUIPJDE:.7 .
2.4 Static Exci ter ..
2.4.1 Field Flashing 2.4.1.1 Source of D.C.
2.4.1.2 Operation Auto / Manual 2.4.2 Normal Exci tatica 2.4.2.1 Power Source 2.4.2.2 Starting / Stopping Exci tatien 2.4.2.3 Emergency Shutdcwn 2.4.2.4 Over excitation 2.5 Gen. Outout Breakers (15-H/J-2) 2.5.1 operatien 2.5.1.1 Auto / Manual 2.5.2 Relaying (86) 2.5.2.1 Actions /Permissives 3.0 D.C. Centrol Fewer System 3.1 Batteries 3 1.1 Ratings 3.1.2 Controls / indications 32 Part. Charcer Pcwcr Source 1876 !32 3 2.1 ,
3.2.2 Operatica 3.2.3.1 Controls / indications
OUALIFICA'"IC'i RECORD
-s NA:G:: PAGr 9 of 9 EMERGENCY DIESEL GEN. SYSTEM SYSTEM: REV. NO. /
(y 77p, ggggggjggg, Sy37,)
I UNIT :0. I and 2 cArz: 11/03/78 Rrq JIP2:E:iT INITIAL 4.0 Ooeration - _
4.1 Ha.:- knc'wledge of appli.:able Tech. Specs. - .,
4.2 Using the control panel in the centrol room, should be able to explain operation of all controls and instrumentation.
4.3 Should be able to perform and/or explain synchrcnizing, loading, and unloading of the diesel gen. .
4.4. At the respective diesel, should b'e able to point out and
~~N,-i explain major system. components, and explain thei r operation ,
as well as the operatiens of all local control panels.
4.5 Should be able to perform applicable PI's.
4.6 Demonstrate the ability to perform the operations in accordance with OP-6. .
5.0 Abnormal and Emergency Procedures 5.1 understand and explain system line-up and opera tion during abnormal or emergency condi tions.
Ve certi fy that has demons trated the e
ability and knowledge to safely operate and control this system.
DATE SHIFT SUPERVISOR OPERATIN3 SUPERVISOR 1876 133
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. N1F S8.22-16 VIRGINIA ECTRIC A'!D PCITER CO!!PA?IY NORTH Id!!A PC:.TR STATIC!!
N OUALIFICATION RECORD NAME: Pact 1 OF 9 SYSTr2 EMEP.GENCY DIESEL GEN. SYSTEM Pr/. No. I mrIT :;o. I and 2 DATr: 11/03/78 arFF.aINCIS : .
. 1. ACT neveley:ent Program Manual: .
- 2. Valve Operating Diagram (s):
- 3. Flew Diagram (s) :
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- 4. Electrical Diagram (s) : FE-21E; 21J .
-s
- 6. System Description (s): 22-12
- 7. North Anna FSAR, Sec.- 8.3
- 8. North Anna Technical Specifications, Sec.: 3/4.8
- 10. Ahner=al Procedure (s) AP-10
- 12. Instrumentation Systems EG
- 13. P S Decument N/A .
- 14. Mfg. Literature Colt Industries, Pwr. Systems Div. Products
- 15. Station curve Ecok 1-SC-5.13 16. FT's: PT-82A; Misc.-14
EXAMPLE EMERGENCY DIESEL EXAM QUESTIONS
- 1. Properly arrange the following components of the Diesel Fuel System into (4) a correct flow path from the 5,000 BBL s torage tank to the individual injecte-
- a. 5,000 BBL Storage Tank
- b. Duplex Filters
- c. Engine injector Pump
- d. Fuel Oil Transfer Pump (s)
- e. Fuel Pumps, Engine & Motor Driven
- f. 50,000 gal. Underground storage Tank
- g. Day Tank
- h. Individual injectcr
- 2. The fuel oil transfer pumps for the diesels are physically located in the (3) fuel oil pump house.
- a. What is the power source for these pumps?
- b. Where are the control switches for these pumps physically located?
- c. With the pump control switch in "AUT0", what condition will s ta rt and stop the pump?
3 What is used to start the emergency diesels? (1)
- 4. What is the cooling medium for the emergency diesel lube oil cooler? (1)
- 6. Assume you are operating a diesel generator for test purposes. (3)
- a. Why is i t desi rable not to run the diesel at less than 75% of full rated load?
- b. List three (3) ccnditions that will cause the diesel to automatically shutdown while in this running configuration.
- c. Cutline the steps you would use to svnchroni ze the diesel gene ra to r ,
and place a load cn it in ;his running ccnfiguration.
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NIF S8.23-1 COMMENT 8.23 Several fires have occured at some operating plants in the area of the diesel engine exhaust manifold and inside the turbocharger housing which have resulted in equipment unavailability. The fires were started from lube oil leaking and accumulating on the engine exhaust manifold and accumulating and igniting inside the turbocharger housing. Accumulation of lube oil in these areas, on some engines, is apparently caused from an excessively long prelube period, generally longer than five minutes, prior to manual starting of a diesel generator. This condition does not occur on an emergency start since the prelube period is minimal.
When manually starting the diesel generators for any reason, to minimize the potential fire hazard and to improve equipment availability, NUREG-0660 recommends that the prelube period should be limited to a maximum of three to five minutes unless otherwise recommended by the diesel engine manufacturer.
Provide the prelube time interval your diesel engine vill be exposed to prior to manual start and if this interval does not agree with the recommendations of NUREG-0660 provide justification why your interval time is acceptable.
RESPONSE
The prelube time interval for our diesel engine is two minutes when a remote-manual start is made. This is done automatically. There is no prelube during an energency start. Uhen the diesel is started locally, prelube must be manually initiated. The procedure for locally starting the diesel limits prelube to no greater than two minutes.
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COMMENT 8.24 An emergency diesel generator unit in a nuclear power plant is normally in the ready standby mode unless there is a loss of of f site power, an accident, or the diesel generator is under test. Long periods on standby have a tendency to drain or nearly empty the engine lube oil piping system. On an emergency start of the engine as much as 5 to 14 or more seconds may elapse from the start of cranking until full lube oil pressure is attained even though full engine speed is generally reached in about five seconds. With an essentially dry engine, the momentary lack of lubrication at the various moving parts may damage bearing surfaces producing incipient or actual component failure with resultant equipment unavailability.
The emergency condition of readiness requires this equipment to attain full rated speed and enable automatic sequencing of electric load within ten seconds. For this reason, and to improve upon the availability of this equipment on demand, it is necessary to establish as quickly as possible an oil film in the wearing parts of the diesel engine. Lubricating oil is normally delivered to the engine wearing parts by one or more engine driven pump (s) . During the starting cycle the pump (s) accelerates slowly with the engine and may not supply the required quantity of lubricating oil where needed fast enough. To remedy this condition, as a minimum, an electrically driven lubricating oil pump, powered from a reliable DC power supply, should be installed in the lube oil system to operate in parallel with the engine driven main lube pump. The electric driven prelube pump should operate only during the engine cranking cycle or until satisfactory lube oil pressure is established in the engine main lube distribution header. The installation of this prelube pump should be coordinated with the respective engine manufacturer.
Some diesel engines include a lube oil circulating pump as an integral part of the lube oil preheating system which is in use while the diesel engine is in the standby mode. In this case an additional prelube oil pump may not be needed.
Indicate whether your design includes an electric prelube oil pump. If your design does not include this pump, provide justification why it is not necessary.
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RESPONSE
North Anna Unit #2 Emergency Diesel Generators do not employ a D.C.
powered L.O. pump. However, a L.O. circulating pump is provided as an integral part of the lube oil preheating system. Additionally, manually started A.C. powered prelube pumps are provided for use during non-emergency starts. Fairbanks Morse recognizes that dry starts will be required in emergency conditions. Our operating procedures require the operation of the prelube pump prior to starting the engine in non-emergency starts.
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N1F S8.25-1
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COMMENT 8.25 Periodic testing and test loading of an emergency diesel generator in a nuclear power plant is a necessary function to demonstrate the operability, capability and availability of the unit on demand. Periodic testing coupled with good preventive maintenance practices will assure optimum equip-ment readiness and availability on demand. This is the desired goal.
To achieve this optimum equipmant readiness status, NUREG 0660 recommends the following:
- 1. The equipment should be tested with a minimum loading of 25 percent of rated load. No load or light load operation will cause incomplete combustion of fuel resulting in the
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formation of gum and varnish deposits on the-cylinder walls, ->
intake and exhaust valves, pistons and piston rings, etc.,
and accumulation of unburned fuel in the turbocharger and exhaust system. The consequences of no load or light load operation are potential equipment failure due to the gum and varnish deposits and fire in the engine exhaust system.
- 2. Periodic surveillance testing should be performed in accordance with the applicable NRC guidelines (R. G. 1.108),
and with the recommendations of the engine manufacturer.
Conflicts between any such recommendations and the NRC guidelines, particularly with respect to test frequency, loading and duration, should be identified and justified.
- 3. Preventive maintenance should go beyond the normal routine adj us tments , servicing and repair of components when a malfunction occurs. Preventive maintenance should encompass investigative testing of components which have a history of repeated malfunctioning and require constant attention and repair. In such cases, consideration shculd be given to replacement of those components with other products which nave a record of demonstrated reliability, rather than repetitive repair and maintenance of the existing components. Testing of the unit af ter adjustments or repairs have been made only confirms that the equipment is operable and does not necessarily mean that the root cause of the problem has been eliminated or alleviated.
- 4. Upon completion of repairs or maintenance and prior to an actual start, run and load test, a final equipment check should be made to assure that all electrical circuits are functional, i.e., fuses are in place, switches and circuit breakers are in their proper position, no loose wires, all test leads have been removed, and all valves are in the proper position to permit a manual start of the equipment. After the unit has been satisfactorily started and load tested, return the unit to ready auto-matic standby service and under the control of the con-trol room operator.
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N1F S8.25-2 Provide a dicussion of whether the recommendations of NUREG-0660 have been implemented in the emergency diesel generator system design and how they will be considered when the plant is in commercial operation, i.e., by what means will the above requirements be enforced.
RESPONSE
- 1. The diesel generators are load tested at 2.5-2.75 MW. This is equivalent to approximately 90 to 100% of rated load.
- 2. The Unit 2 diesel surveillance requirements for demonstrating the oper-ability of the diesel generators are in accordance with the recommendations of Regulatory Guide 1.108 " Periodic Testing of Diesel Generator Units Used as Onsite Electric Power System at Nuclear Power Plants", Revision 1, August 1977. This is described in the Bases section of the Proof and Review copy of the Unit 2 Technical Specification.
Surveillance testing of the diesel generators does not conflict with the recommendations of the engine manufacturer.
- 3. The preventive maintenance program includes normal routine adjustments and servicing of components. When any part on the diesel needs to be repaired or replaced, a maintenance report (MR) is initiated. After the repair has been finished, the completed maintenance report is logged onto a computer. Therefore if any item is suspected of having a history of repeated malfunctions, it can be " called up" and all MR's will be listed which have been performed with respect to that item.
- 4. When repairs or maintenance is to be performed on the diesel, operations will release the diesel to the maintenance department af ter completing the first part of the Maintenance Operating Procedure (MOP). Maintenance personnel will perform all diesel maintenance in accordance with an approved procedure as required by the Nuclear Power Station Quality Assurance Manual (NPSQAM). The approved maintenance procedures require the replacement of equipment removed for repair. Following the repair of the 1876 140,
N1F S8.25-3 diesel caintenance personnel would return control of the dieset to operations. The diesel would then be returned to operable status and a functional check conpleted as required by the second part of the MOP. During the f unction check mair. enance personnel would inspect their work, if required.
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CO>tMENT 8. 26 The availability on demand of an emergency diesel generator is dependent upon, among other things, the proper functioning of its controis and monitorir.g instrumentation. This equip-ment is generally panel mounted and in some instances the panels are mounted directly on the diesel generator skid.
Major diesel engine damage has occurred at some operating plants from vibration induced wear on skid mounted control and monitoring instrumentation. This sensitive instrumentation is not made to withstand and f unction accurately for prolonged periods under continuous vibrational stresses normally en-countered with internal coubustion engines. Operation of sensitive instrumentation under this environment rapidly deteriorates calibration, accuracy and control signal output.
Tnerefore, except for sensors and other equipment that must
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be directly counted on the engine or associated piping, NUREG-0660 recommends that the controls and monitoring instrumentation be installed on a free standing floor mounted panel separate from the engine skids, and located on a vibration free floor area or equipped with vibration mounts.
Provide a description of how the controls and monitoring systens are installed and indicate how your design addresses the recommendations of NUREG-0660.
RESPONSE
There are three control cubicles in the diesel generator room. One of these cubicles, which consists of three panels, is floor mounted separate from the engine skid. Two control cubicles are skid mounted. All of the devices in the skid mounted control cubicles, as well as those in the floor mounted cubicle, have been seismically qualified by a combination of static analysis and testing. Since the diesel generator units have been operated over a period in excess of three years without vibration induced failures in the control equipment, it is felt that this equipment is satisfactory.
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a- . -I COMMENT 8.27 Experience at operating plants hau shown that a diesel engine that is provided with an engine cooling water temperature control system employing a 3-way bypass-type thermostatically controlled valve have demonstrated consistent trouble free operation over engines provided with other methods of temperature control such as shutter controls radiators. Does your system employ a water thermostat of the 3-way or bypcss-cype which splits the water flow no only as much water passes through the cooler or radiator as needed to maintain the proper outlet temperature? If your engine cooling water system does not use a 3-way valve, describe your installed system and justif y its design as opposed to a design empicying a 3-way valve.
RESPONSE
horth Anna Unit #2 Emergency L;esel Generator engine cooling system em-ploys a AMOT 3-way bypass-type thermostatically controlled valve on all Emergency Diesel Generators, thereby, complying with NUREC/CR-0660.
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