ML13330B477

Forwards Clarifications to Util 870709 Comments on Preliminary SER on Operability of Unit Standby Diesel Generators,Per 890117 Meeting.Recommendations in Table a Will Continue to Be Implemented

ML13330B477
Person / Time
Site:	San Onofre
Issue date:	02/14/1989
From:	Nandy F SOUTHERN CALIFORNIA EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 8902170257
Download: ML13330B477 (28)

Text

Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD, CALIFORNIA 91770 F

R. NANDY TELEPHONE MANAGER OF NUCLEAR LICENSING (818) 302-1896 February 14, 1989 U. S. Nuclear Regulatory Commission Attention:

Document Control Desk Washington, D.C.

20555 Gentlemen:

Subject:

Docket No. 50-206 Standby Diesel Generators San Onofre Nuclear Generating Station Unit 1

References:

A. Letter dated January 28, 1987, from G. E. Lear (NRC) to K. P. Baskin (SCE), Safety Evaluation Report on the Operability/Reliability of Emergency Diesel Generators Manufactured by Transamerica Delaval, Inc. (TDI)

B. Letter dated July 9, 1987, from M. 0. Medford (SCE) to the NRC, Standby Diesel Generators Reference A transmitted a preliminary safety evaluation report (SER) on the operability/reliability of the San Onofre Unit 1 standby diesel generators.

Reference B provided Southern California Edison's (SCE's) comments and clarifications on this preliminary SER and also stated SCE's intent to implement the actions described in the SER, subject to the comments and clarifications of Reference B.

At an SCE-NRC meeting on January 17, 1989, the nature and purpose of SCE's comments were discussed.

During these discussions, it became apparent that some of the points made by SCE in Reference B needed additional clarification or justification, while certain other positions were no longer applicable due to recent changes in engine load restrictions, engine hardware modifications and successful results of component inspections. It was, therefore, decided in the meeting that SCE would submit an update of its positions and commitments with respect to the SER.

The enclosed Table A contains a comprehensive listing of all PNL recommendations as endorsed by the SER for implementation at San Onofre Unit 1. SCE is implementing, and will continue to implement, all of the recommendations listed in Table A, subject to the comments and clarifications provided in Table A and in the SER.

8902170257 890214 DIR ADCOCK 05 002 06

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-2 Table B provides SCE's comments on the "sample license conditions," which were included as Appendix A and Enclosure 2 to the SER. A modified version of some

'of these sample license conditions will be submitted by SCE by February 17, 1989, for NRC approval and incorporation into the San Onofre Unit 1 license.

With respect to the remaining individual sample license conditions, it is SCE's position that they should not be made license conditions, but should rather be part of the overall diesel maintenance and surveillance (M/S) program, which will be proposed as one of the license conditions in the forthcoming submittal.

If there are any questions, please call me.

Very truly yours, Enclosures cc: C. M. Trammell, NRR Project Manager, San Onofre Unit 1 J. B. Martin, Regional Administrator, NRC Region V F. R. Huey, NRC Senior Resident Inspector, San Onofre Units 1, 2 and 3

(Revised)"

TABLE A COMMENTS ON SAFETY EVALUATION REPORT SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS 2

Evaluation Subject to a few clarifications as identified in this SER SCE is implementing the conclusions NRC staff concurs with the conclusions and recommendations and recommendations of the four PNL of PNL-5600, PNL-5336, PNL-5444 and PNL-5718, which are reports as applicable to San Onofre incorporated into this SER by reference.

Unit 1, subject to the clarifications identified in the SER and in this transmittal and also subject to specific.agreements with the NRC (e.g., engine load restrictions).

2.1 Technical Resolution of Phase I, 2.1.1 In addition to OG findings and recommendations, implement the findings and recommendations in the following sections of PNL-5600 subject to SER Section 2.1.3 clarifications,and exceptions.

Section Component 4.1.4.2 Air start valve capscrews 4.2.4.3 Auxiliary module wiring and terminations 4.4.4.4 DSRV-4 connecting rods 4.5.4.2 Connecting rod bearing shells 4.8.5.6 DSRV-20-4 cylinder crankshafts 4.9.5.2 Cylinder block 4.10.4.3 Cylinder heads 4.11.4.3 Cylinder head studs 4.13.4.2 DSRV engine base and bearing caps 4.14.4.2 Fuel oil injection tubing 4.15.4.3 Jacket water pump 4.16.3.3 Piston skirts (type AE 4.16.4.3 Piston skirts (modified type AF) 4.17.4.3 Push rods 4.18.4.3 Rocker arm capscrews 4.19.4.3 Turbochargers

(Revi sed)

-2 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS 2.1.2 This section is explanatory (no specific recommendations).

2.1.3 This section is explanatory (no specific recommendations).

2.1.3.1 Engine Overhaul Frequency Perform major engine overhauls at 10 year intervals per current OG recommendation instead of 5 year intervals, which was originally proposed by OG and endorsed by PNL.

Perform sample inspection of major engine components on a one time basis following 5 years of service.

2.1.3.2 Air Start Capscrews Verify on sampling basis, air start capscrews on each engine are of length 2 3/4 inches.

Following initial installation of capscrews with torque of 150 ft lb, retorque capscrews every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> until no further change in torque is noted.

Section 4.1.4.2 of PNL-5600 recommends that periodic checks include retorquing following first period of engine operation after replacement of copper gasket that seals air start valve housing in cylinder head. This is to ensure that no additional gasket creep occurs as a result of the additional thermal and mechanical stresses.

2.1.3.3 Auxiliary Module Wiring and Terminations PNL recommendations are same as OG recommendations.

2.1.3.4 Connecting Rod Bearing Shells DR/QR Appendix II matrix does not satisfactorily address need for Oil contamination analyses periodic oil contamination analyses. NRC will require that this are performed monthly, in matter be addressed satisfactorily in plant specific M/S programs.

accordance with Owners Group

(Revi sed)

-3 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS (Section 4.5.4.2 of PNL-5600 recommends oil contamination analysis MIS recommendations be performed on a regularly scheduled basis as recommended by the oil supplier to provide early warning of deterioration of bearing shells or warn of other developing engine or lubrication problems.)

2.1.3.5 No such subsection In SER.

2.1.3.6 DSR-48 Connecting Rods Not applicable 2.1.3.7 DSRV Connecting Rods Preservice Inspections The pre-service inspections for connecting rods recommended in PNL's pre-service recommendations Section 4.4.4.4.1 of PNL-5600 should be fully implemented as apply to new connecting rods. At follows:

the time of SER issuance (1/28/87),

the connecting rods of both diesel Rod eyes and rod-eye bushings should be subject to the same generators at San Onofre Unit 1 had inspections recommended for the in-line connecting rods in completed hundreds of hours of Section 4.3 of PNL-5600, which are:

service.

Therefore, no "pre-service" inspections were performed.

o During any disassembly that exposes the inside diameter of a rod-eye bushing, the surface of the bushing should be examined with liquid penetrant to verify the continued absence of linear indications in the heavily-loaded zone within

+15 degrees of the bottom dead center position.

o Any rod eye not previously examined in accordance with the acceptance criteria recommended by FaAA should be examined using an appropriate nondestructive technique at the first major (5-year) engine disassembly. No indications deeper than 0.04 inch should be allowed.

Rod bow should be within FaAA recommended limits.

Inspections of lower connecting rod assemblies of all rods should include:

(Revi sed)

-4 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS o

Bolt holes in link rod box All threaded holes for connecting rod bolts should be inspected using appropriate non-destructive technique to verify the absence of pre-existing flaws. PNL infers from FaAA-84-3-14 that any indication over 1/8 inch in depth in the pair of bolt holes immediately above the crankpin is rejectable. All indications should be recorded for engineering evaluation.

o Connecting rod bolts All connecting rod bolts should be examined. The DR/QR reports call for a magnetic particle test (MT), but do not specify the technique. In future examinations, PNL recommends that these bolts be examined using the wet fluorescent MT technique (in conjunction with a yoke) rather than the dry particle technique (and direct-current prods).

The wet fluorescent technique would provide the enhanced sensitivity normally specified for bolt examinations.

The washers used with the bolts should be examined visually for signs of galling, as specified in the Comanche Peak and Grand Gulf DR/QR reports.

o Connecting rod bolt torque All connecting rod bolts should be lubricated in accordance with the engine manufacturer's instructions and torqued to the specifications of the manufacturer. As discussed in FaAA-84-3-14, the current torque specifications for the 1-1/2-inch bolts and the 1-7/8-inch bolts are, respectively, 1700 ft-lb and 2600 ft-lb.

PNL suggests that the lengths of the two pairs of connecting rod bolts above the crankpin be measured ultrasonically pre and post-tensioning. These measurements would provide an accurate check on whether or not the desired bolt stretch has been achieved through application of the specified torque.

(Revised)

-5 SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS In addition, these measurements would provide a useful reference for later ultrasonic checks of bolt preload.

FaAA-84-3-14 and the DR/QR report for Grand Gulf recommend that breakaway torque be measured at any time the link rod box is disassembled, and that the bolts, bolt holes, and contact surface areas be carefully examined if the breakaway torque is less than 1600 ft-lb for 1-1/2-inch bolts or less than 2400 ft-lb for 1-7/8-inch bolts. PNL notes that breakaway torque may not be an accurate measure of bolt preload, particularly after a connecting rod has been in service. Inaccuracies may be introduced by such factors as thread galling. Ultrasonic measurements of bolt length would provide a more reliable check because they would not be affected by the condition of the threads.

o Contact at serrated joint The contact between mating surfaces of the link rod box should be no less than the minimum specified by the engine manufacturer. The percentage of contact should be verified for each joint using an appropriate method (e.g., "blueing").

o Link rod clearance Clearance between the link pin and the link rod should be examined. PNL concurs with FaAA's recommendation that this dimension must be zero when the link rod bolts are torqued to 1050 ft-lb as specified by the manufacturer.

Periodic Inspections NRC staff finds PNL recommended periodic inspections have generally been incorporated in Revision 2 of M/S program. NRC has the following comments.

Perform baseline ultrasonic elongation measurements on all connecting rods at first availability, i.e., on 25% of the connecting rods at the next 25% sample inspection and on 100% of the connecting rods at the next 10 year overhaul inspection.

R(Revised)

-6 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS Revision 2 of M/S program recommends ultrasonic measurement of connecting rod bolt stretch prior to each bolt disassembly.

However, as part of the plant specific program, baseline ultrasonic measurements should also be required following each bolt assembly.

NRC staff concurs with PNL's recommendation that if connecting rod bolt tension is found to be reduced to less than 93% of its initial value as measured during installation. then the cause should be determined. appropriate corrective action should be taken and the interval between checks of bolt tension should be reevaluated. (Note: NRC staff considers only ultrasonic measurements and not torque measurements to be sufficiently reliable to compare with the 93% criterion.)

M/S matrix calls for a one time check rather than the periodic checks recommended by PNL regarding degree of surface contact at the serrated joint (of the connecting rod assembly) and the zero clearance condition between the link pin and link rod. Licensees should consider future checks of surface contact in the event that periodic inspections should reveal excessive detensioning of the connecting rod bolts, fretting of the serrated surfaces or other evidence of connecting rod distress.

PNL recommends that an "appropriate-nondestructive method" be employed for preservice and periodic inservice inspection of bolt holes in link rod bore. NRC staff concludes this inspection method shall include either (1) the eddy current inspection.

method developed by FaAA for threaded carbon steel bolt holes (i.e., FaAA procedure NDE 11.9, Revision 1 or (2) an alternative method shown to be equivalent to FaAA eddy current procedure for purposes of discriminating small cracks in the threads.

NRC staff will incorporate key M/S actions as license conditions for TDI facilities with DSRV connecting rods (see Appendix A of SER for sample license conditions).

(Revi sed)

-7 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS 2.1.3.8 Crankshafts (All TDI Models)

Appropriate precautions should be taken for all engine models to Plant procedures have been prevent sustained engine operation in an unbalanced condition.

changed to incorporate these Plant procedures should clarify that the hourly cylinder exhaust recommendations.

temperatures that are taken per Table 1 of the M/S matrix should also be monitored for engine imbalance.

2.1.3.9 through 2.1.3.11 Not applicable to San Onofre Unit 1.

2.1.3.12 Crankshafts (DSRV-20)

Pending completion of efforts related to alleviation of transient During the 1988-1989 refueling outage, torsional stresses, San Onofre Unit I crankshafts should be main journals No. 8 through 12 on the inspected at each refueling per Revision 2 of M/S program. Key crankshafts of both diesel engines periodic inspection items will be incorporated as license were inspected with liquid penetrant.

conditions (see Appendix A of SER).

Per Section 4.8.5.6.2 of No cracks were found. If during PNL-5600, "If cracks reinitiate in the oil holes where they were future crankshaft inspections new previously discovered and removed, or if cracks initiate in other cracks are found, SCE's contingency crankshaft surfaces, they should be removed and the adequacy of plan to fix these cracks and the the repaired crankshaft(s) should be reanalyzed as a prerequisite reporting requirements of the license to additional service. This analysis should address whether or conditions will be implemented.

(The not the new cracks and the operating history under which they proposed contingency plan and the developed are consistent with the predictions of the analysis proposed reporting requirements will documented in FaAA-84-12-14 (April 1985).

The analysis and the be submitted to the NRC under conclusions drawn from it should be subject to NRC review."

separate cover by February 17, 1989.

Depending on the outcome of this evaluation, NRC staff may require that cracking problem be corrected prior to plant restart.

San Onofre Unit 1 Technical Specifications (TS's) should be revised The 4500 kW + 5% load limit is no to limit surveillance test load to 4500 kW + 5%. Engine operating longer applicable.

Engine operating procedures and training should be revised as necessary to guide procedures and initial operator and instruct operators against overloading beyond 4500 kP + 5%.

training will be revised as necessary to guide and instruct operators against overloading beyond TS

(Revi sed)

SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS load limit. Additional steps will be taken to ensure that each individual operator has knowledge of this limit.

If crankshaft is loaded beyond 4500 kW + 5% for some unspecified The 4500 kW + 5% load limit is no reason, contingency inspection will be required as a license longer applicable. For additional condition. (See Appendix A of SER) comments, see Table B.

SCE should submit clarification to the NRC that the monthly slow These actions have been completed.

starts will be at least 24 seconds in duration. Plant TSs should (See NRC Amendment No. 104, dated be revised accordingly as soon as practicable.

7/22/88 to the San Onofre Unit 1 POL.)

Per Section 4.8.5.6.3 of PNL-5600:

A. To avoid cylinder imbalance, (1) cylinder exhaust gas temperatures should be monitored during engine operation to verify that differences between individual cylinder temperatures and the average temperature for all cylinders remain within the range recommended by TDI; (2) cylinder firing pressures should be measured no less frequently than the interval recommended by TDI; and (3) SCE should analyze the trends of cylinder pressure and temperature measurements to detect changes that might indicate a need for maintenance of fuel injection equipment. Any abnormalities should be corrected expeditiously.

B. Continuous engine operation at speeds more than a few rpm Plant procedures have been above 450 rpm should be avoided, particularly during engine changed to caution operators startup (imbalance in cylinder firing more likely).

Operators against continuous engine should be made aware of this situation.

operation at speeds more than a few rpm above 450 rpm. However, during engine startup, speed transients are unavoi dab le.

A and B above should be incorporated into plant operating and surveillance testing procedures.

(Revi sed)

-9 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS PNL-5600 also recommends:

"All accessible gears in the gear train should be inspected at the next refueling outage to verify their continued satisfactory condition.

The remaining gears should be inspected during the next major engine disassembly, unless an earlier inspection is indicated by the condition of the gears inspected during the next refueling outage."

2.1.3.13 Engine Block See Appendix A of SER for license conditions.

Stud-to-Stud Cracks (The blocks of engines that have been operated without block top inspection or that have been operated for a time in excess of the allowable fatigue damage index described in the FaAA report should conservatively be assumed to have ligament cracks (see p. 4.142 of PNL-5600))

FaAA recommends that blocks with known or assumed ligament cracks All four block top halves were should be inspected following each operation in excess of 50% of inspected with NDE during 1985-86 nameplate load to verify the continued absence of stud-to-stud and after each engine had provided stud-to-end cracks. PHL recommends that eddy-current testing or a hundreds of hours of service.

similarly sensitive nondestructive testing technique should be used No cracks were found.

Based on to perform these inspections. SER concurs with Owners Group this favorable finding and FaAA's clarification that these inspections may be performed using a analytical prediction that cracks boroscope with heads in place and should be performed within if they occur, initiate at the block 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after engine shutdown.

top surface where the stresses are the highest, visual block surface inspections provide adequate assurance of continued absence of cracks. Whenever the engine is operated in excess of 50% of nameplate load for one hour or more,

(Revised)'

-10 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS a visual inspection of the block having cidmanstaetten graphite is, and will continue to be, performed under intense light within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> of engine shutdown.

The visual inspection may be performed directly or with boroscope.

FaAA recommends that, if a stud-to-stud crack or stud-to-end crack See Table B is discovered, a detailed inspection be performed to ensure that the crack extends no more than 1.5 inches in depth from the block top.

PNL recommends further that the engine not be returned to nuclear service pending further analysis of the crack and its implications for engine reliability. The analysis and the conclusions drawn from it should be subject to NRC review before the engine is returned to service.

(SER has incorporated these inspections as sample license conditions.)

Circumferential Cracks in Liner Bore PNL concurs with FaAA that circumferential cracks do not represent a hazard to engine reliability. However, PNL recommends that any time a cylinder liner is removed, the liner landing should be inspected for circumferential cracks. If a crack is found, its length and depth should be characterized through appropriate nondestructive tests.

The characteristics of the crack should be evaluated relative to FaAA's predictions for circumferential crack behavior.

PNL does not recommend removal of cylinder liners for the sole purpose of this Inspection.

Camshaft Gallery Cracks (These inspections are for inline engines only and are not applicable to San Onofre Unit 1.)

(Revised)

-11 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS Inspections of Cylinder Liners Per PNL Section 4.9.5.2, referring to PNL Section 4.9.3.1.2, Accessible areas of-the cylinder visual inspection of cylinder liners is recommended at each liners are, and will continue to refueling to monitor wear. Boroscopic inspection is acceptable be, visually inspected at each if the cylinder heads are not to be removed. Per PNL Section refueling to monitor wear.

4.9.5.2, if cumulative results of these inspections over several power plant fuel cycles show that one or more of the inspections reveal nothing of significance, the scope and/or frequency of the inspections could be reconsidered. PNL recommends that any changes be subject to NRC review before they are implemented.

Liquid Penetrant Inspections of Block Top P.4.148 of PNL-5600 states, "Blocks with known or assumed ligament This item has been completed cracks should be inspected at each refueling outage, to determine in accordance with the whether or not cracks have initiated on the top surface exposed by Owners Group H/S program.

the removal of two or more cylinder heads. This process should be repeated over several refueling outages until the entire block top has been inspected. Liquid-penetrant testing or a similarly sensitive nondestructive testing technique should be used to detect cracking, and eddy current should be used as appropriate to determine the depth of any cracks discovered."

For liquid penetrant inspections of engine block top at future refueling outages, Section 4.9.5.2 of PNL-5600 recommends the inspection procedures found in Section V of the ASME Code and the acceptance criteria found in ASME SA-613, Sections 19 and 20, in lieu of ASTM E125 which is the standard referenced in the DR/QR reports. Even though NRC staff has not evaluated the merits of this recommendation, licensees should consider including this recommendation in their M/S program.

(Optional) If a "stud to-stud" or "stud-to-end" crack is discovered, see license condition in Appendix A of SER.

(Revi sed)

-12 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS 2.1.3.14 Cylinder Heads For Group III heads, NRC staff finds 25% sample inspection to During 1987, installation of be acceptable, as expressed in plant-specific DR/QR reports.

Group III cylinder heads on both PNL Section 4.10.4.3 suggests engine owner may choose to bar-over engines was completed. These the engine before it is air-rolled, to reduce the possibility of heads were purchased from Imo engine damage in the event water is present in the cylinder.

Delaval to the Owners Group (See license condition regarding air roll in Appendix A of SER.)

specified criteria. The heads will be re-inspected on a sampling basis at the next 5 year interval, per Owners Group M/S program.

Per Section 4.10.4.3 of PNL-5600, cylinder heads with any through-wall weld repair of fire deck should not be placed in nuclear standby service if repair was performed from one side only

("plug weld"). Since coolant side of fire deck is not readily accessible for welding, a repair from the combustion side might leave defects on the coolant side that would compromise the head integrity.

NRC staff recommends that the following PNL-5600 recommendations regarding future cylinder head inspections should be considered for inclusion in M/S program:

"Currently, ASTM E125 is referenced as the standard for determining whether or not linear indications, shrinkage, inclusions, or porosity are reportable. PNL notes that this standard applies only to magnetic particle (MT) inspections.

Further, PNL notes that ASTM E125 uses references photographs that were assembled by, and for, the foundry industry, and specifies acceptance standards by defect type rather than by the measured dimensions of MT indications.

Thus, field inspection personnel must identify the type of defect represented by the indication to determine whether or not the defect is reportable.

In PNL's opinion, it is preferable for field-usable criteria to

(Revi sed)-.

-13 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS be based on measured dimensions specified in acceptance standards that are readily available at nuclear power plant sites.

(Optional)

PNL recommends that alternative procedures and acceptance criteria be used in future cylinder head inspections. A well-established methodology for MT examinations may be found in Section V, Article 7 of the ASME Code (1983), and acceptance criteria for MT examinations may be found in ASME SA-613, Section 19. Methodology for liquid penetrant examinations may be found in ASME Section V, Article 6, and acceptance criteria in ASME SA-613, Section 20. The ASME standards just referenced are widely used throughout the nuclear industry." (Optional) 2.1.3.15 Cylinder Head Studs M/S program should incorporate procedures for installing cylinder The installation procedure head studs, as identified in Owners Group letter to utilities dated highlighted in the referenced September 24, 1984.

Owners Group letter for straight shank studs is being implemented. In addition, the Owners Group letter refers to a future TDI Service Information Memo (SIM) which TDI (Imo Del'aval) no longer plans to issue.

2.1.3.16 Engine Base-All Models For engine bases which have been shown to be crack free, base inspection intervals should be consistent with OG recommendations.

For bases in which cracks were found to exist, per Section 4.17.4.2 of PNL-5600, monitor for crack growth by magnetic particle or liquid penetrant inspection at alternate refueling outages.

(Revi sed)

-14 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS Note:

PNL concurs that it is not necessary to remove the coating to perform the visual inspection.

Check each engine base for degenerate Widmanstaetten graphite and During Cycle X refueling, report to NRC if found, with detailed assessment as to adequacy of both engine bases are being engine base.

checked for Widmanstaetten graphite.

Samples were taken and sent to Failure Analysis Associates (FaAA) for analysis.

Preliminary results received from FaAA (via telecon) indicate that Sindmanstaetten graphite is present in the DG#l engine base but not in the DG#2 engine base. A detailed report as to adequacy of the engine base will be submitted to the NRC after the assessment is completed.

2.1.3.17 Fuel Oil Injection Tubing Per Section 4.14.4.2 of PNL-5600, (1) Replacement fuel oil injection tubing should be SAE-uo rather than SAE-1008 steel.

(2) Fuel lines should be shrouded (if not shrouded, should be shrouded at the first refueling outage).

(3) Newly installed tubing and fittings should be inspected for wetness or other signs of leakage during engine shutdown after operation.

(4) Plant M/S program should include manufacturer's instructions concerning installation and inspection of fuel line fittings.

(Revi sed)

-15 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS (5) Replacement tubing should be examined over its full length prior to bending and any tubing with flaws deeper than 0.003 inch should be rejected. This full length inspection is recommended because of intermittent indications having been found in injection tubing already examined. PNL suggests an eddy-current probe capable of traversing the entire tube bore be used for this examination (i.e., examination would be from inside the tube rather than outside).

NRC considers items (1), (2) and (3) to be optional.

2.1.3.18 Jacket Water Pump Per Section 4.15.3.3.3 of PNL-5600, confirm that the following These actions were completed during SWEC recommendations regarding the DSRV-20 engine jacket water Cycle X refueling for both diesels.

pump assembly have been fully implemented or incorporated into plant M/S program:

o The impeller end of one shaft should be inspected for overtorquing damage at the first available maintenance outage, and the nut should be torqued to 150 ft-lb. The second pump should be similarly inspected at the next refueling outage.

o The gear end of the shafts should also be inspected at the next refueling outage, and the gear nut should be torqued to a value not to exceed 290 ft-lb.

o The SWEC recommended torque limits (between 100 and 150 ft-lb for impeller nut and between 200 and 290 ft-lb for gear nut) should be added to the assembly procedure for the pumps.

.o Keys should be properly fitted in both ends of the pump shaft.

o A second hole should be added in the gear end of the pump shaft to facilitate adequate insertion of the locking cotter pin.

(Revi sed)

-16 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS 2.1.3.19 Piston Skirts (Type AE)

Require AE piston skirts to be inspected at first 10 year overhaul.

NDE methods other than liquid Per PNL-5600, the inspections should be with liquid penetrant and, penetrant and eddy current should as appropriate, with eddy current. Inspected areas should include also be permitted for the piston stud boss area, rib area near wrist pin boss and intersection of skirt inspection. It is requested rib with wrist pin boss. The acceptance criteria used for these that the safety evaluation report inspections are summarized in PNL-5600, Section 4.16.3.3.

incorporate this provision.

2.1.3.20 Piston Skirts (Modified Type AD)

Load limitations will remain in place for Type AF piston skirts Since all piston skirts even after crankshafts have been modified. See Appendix A of SER are now type AE, this for license conditions. Acceptance criteria for the inspections recommendation is no required by the license conditions are stated in PNL-5600, longer applicable.

Section 4.16.3.3.

2.1.3.21 Piston Skirts (Type AH and AN)

(Not applicable to San Onofre Unit 1.)

2.1..22Push Rods L

Friction-welded design push rods should be liquid penetrant inspected before service.

Subsequent radiograph inspection and destructive examination recommended by PNL-5600 are optional to utility.

PNL also suggests that new friction welded push rods may be examined simultaneously and inexpensively by radiography, to ensure the presence of "lips" inside the tube, as evidence of a sound friction weld. (Optional)

Ball-end design for push rods is not acceptable.

Rocker Arm Capscrews 2.1.3.23 -

Revision 2 of OG M/S program is satisfactory.

(Revi sed)

-17 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS 2.1.3.24 Turbochargers:

Limit the maximum cylinder exhaust temperature to 1050*F to ensure turbine inlet temperature does not exceed manufacturer's recommendations.

Implement full flow lubrication during engine coast down (optional).

Incorporate in M/S program quarterly spectrochemical and ferrographic oil analyses recommended by FaAA to provide early evidence of bearing degradation.

Plant M/S program shall specify that any turbocharger in which nozzle ring anomalies are found as the result of OG recommended inspections be reinspected at the next refueling outage.

Plant M/S program should clarify that the provision to Since no Elliot redesign for discontinue nozzle ring inspections after nozzle rings of nozzle rings is available, SCE an appropriate redesign have been installed does not apply plans to continue the nozzle to the turbocharger inspections which are performed at ring inspections.

5 year intervals (but applies to inspection of one turbocharger per refueling outage).

See Appendix A of SER for license conditions.

2.2 Technical Resolution of Phase II Nuclear Unit 1 DR/QR program for Phase II should be fully implemented for the Nuclear Unit 2 engines.

Per Section 4.0 of PNL-5336 and PNL-5444, incorporate into plant M/S program the additional PNL recommendations relating to improvements for seven components.

(Revi sed)

-18 SER SECTION RECOMMENDATION/LICENSE CONDITION COMMENTS Each individual owner should implement all Owners Group recommendations stemming from plant specific Phase II evaluations.

2.3 MIS Program Prior to issuing final plant specific SER, NRC will require SCE's commitment to an acceptable M/S program that incorporates the following elements.

(1) The recommendations concerning operation, testing, inspection, The current M/S program for maintenance, adjustment, overhaul and repair of the engine as San Onofre Unit I is based on the incorporated in the TDI Instruction Manual, Service Information three elements identified in the Memos (SIMS), and TDI correspondence on specific M/S issues.

SER, as modified by comments provided in SCE-NRC letters (2) The M/S recommendations developed by the Owners Group in dated 6/20/86 and 12/10/87.

SCE's Appendix II, Revision 2, of the DR/QR reports.

commitment to this program is considered to supercede SCE's (3) Additional Phase I items required per Section 2.1.3 of SER.

previous interim commitment to PNL-5304, which was made in SCE-NRC letter dated March 3, 1985.

Revisions to M/S program subsequent to issuance of final plant specific SER should be subject to 10 CFR 50.59 review. Changes to license conditions will be subject to NRC approval.

3.

Conclusions As stated in SER.

As stated above.

NOTES:

DR/QR = Design Review and Quality Revalidation M/S = Maintenance and Surveillance SER = Safety Evaluation Report IAA:9923F

(Revised)

TABLE B COMMENTS ON APPENDIX A AND ENCLOSURE 2 OF SAFETY EVALUATION REPORT (SER)

The following paragraphs provide SCE's comments on the sample license conditions, as stated in Appendix A and Enclosure 2 of the SER.

General Comment With the exception of the items numbered 1, 3, 6, 7 and 9 below, the individual items of Appendix A and Enclosure 2 should not be made license conditions. In the case of items numbered 1, 3, 6, 7 and 9, SCE will be submitting a formal amendment application to the San Onofre Unit 1 license to incorporate these items, as shown revised below, as license conditions. Items numbered 5, 8, 10, 11 and 13 should be deleted, for the reasons provided below. The remaining items should be revised as shown below and incorporated into the NRC approved diesel engine M/S program.

Specific Comments

1. First paragraph of Item No. 1 (General)

Present Wording "Changes to the maintenance and surveillance program for the TDI diesel engines, as identified in [

]*, shall be subject to the provisions of 10 CFR 50.59."

Requested Wording "A diesel engine maintenance and surveillance program as described in the Safety Evaluation Report on the Operability/Reliability of Emergency Diesel Generators Manufactured by Delaval, Inc. (TDI),

dated _

, is to be implemented. Changes to this program will be subject to the provisions of 10 CFR 50.59."

Basis for Change The requested wording covers both the NRC approved initial M/S program and subsequent changes to this program.

2. Fourth Condition of Item No. 2 (Connecting Rods)

Present Wording "All connecting-rod bolts should be visually inspected for thread damage (e.g., galling), and the two pairs of connecting rod bolts above the crankpin should be inspected by magnetic particle testing (MT) to verify the continued absence of cracking. All washers used with the bolts should be examined visually for signs of galling or cracking, and replaced if damaged."

(Revised)

-2 Requested Wording "All connecting-rod bolts will be visually inspected for thread damage (e.g., galling), and the two pairs of connecting rod bolts above the crankpin will be inspected by an appropriate NDE to verify the continued absence of cracking. All washers used with the bolts will be examined visually for signs of galling or cracking, and replaced if damaged."

Basis for Change This allows for alternative NDE methods.

3. First Condition of Item No. 4 (Crankshafts)

Present Wording "Oil hole locations in the five most heavily loaded main journals (i.e., journals 8 through 12) for each crankshaft shall be inspected at each refueling outage with liquid penetrant. Indications found shall be evaluated with eddy current testing as appropriate."

Requested Wording "Crankshaft journal Nos. 9 and 10 on both diesel generator units are to be inspected at each refueling outage until the issue of crankshaft cracking has been resolved."

Basis for Change Inspection experience and FaAA analyses show that cracks will first initiate and propagate most rapidly in the #9 journal oil hole followed by the #10 oil hole. Inspection of the #9 and #10 oil holes will reveal if cracking has reinitiated. Comprehensive crankshaft inspections during major engine overhauls are adequate to cover the less critical areas. Alternative NDE methods should be permitted.

4. Second Condition of Item No. 4 (Crankshafts)

Present Wording "During each major engine overhaul, the fillets of the most highly loaded main journals (Nos. 4 through 12) should be inspected together with the oil holes, using liquid penetrant. Indications found shall be evaluated with eddy current testing as appropriate. In addition, these inspections should be performed for the oil holes and fillets in at least three of the crankpin journals at each major engine overhaul."

(Revised)

-3 Requested Wording "During each major engine overhaul, the fillets of the most highly loaded main journals (nos. 4 through 12) together with the corresponding oil and dowel pin holes will be inspected with an appropriate NDE. Any indications found will be recorded for engineering evaluation and appropriate corrective action(s). In addition, these inspections will be performed for the oil holes and fillets in at least three of the crankpin journals at each major engine overhaul."

Basis for Change This clarifies that dowel pin holes will also be inspected and allows for alternative NDE methods and reliance on engineering evaluation to determine appropriate corrective action(s).

5. Third Condition of Item No. 4 (Crankshafts)

Present Wording "The following actions shall be performed if the engines are operated in excess of 4500 kW (+5%):

(NOTE: Specific actions applicable to San Onofre Unit 1 have not yet been developed. These actions should be specified in a manner similar to what was done for River Bend)."

Requested Wording None. Delete this condition.

Basis for Change The 4500 kW load restriction is no longer applicable to San Onofre Unit 1. For additional comments on load restrictions, see last page of this Table B.

6. Fourth Condition of Item No. 4 (Crankshafts)

Present Wording "If cracks are found during inspections of crankshafts, this condition shall be reported promptly to the NRC staff and the affected engine shall be considered inoperable. The engine shall not be restored to "operable status" until the proposed disposition and/or corrective actions have been approved by the NRC staff."

(Revised)

-4 Requested Wording "If during these inspections cracks are found in the oil holes or in other crankshaft surfaces, these findings are to be reported to the NRC within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The affected engine is to be considered inoperable and is not to be restored to operable status until the proposed disposition and/or corrective actions have been approved by the NRC staff."

Basis for Change "Promptly" is defined as "within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />" to make the reporting requirement better understood and implemented.

7. First Condition of Item No. 5 (Cylinder Blocks)

Present Wording "Cylinder blocks shall be inspected for "ligament" cracks, "stud-to-stud" cracks and "stud-to-end" cracks as defined in a report by Failure Analysis Associates, Inc. (FaAA) entitled, "Design Review of TDI R-4 and RV-4 Series Emergency Diesel Generator Cylinder Blocks" (FaAA report no. FaAA-84-9-11.1) and dated December 1984.

(Note that the FaAA report specifies additional inspections to be performed for blocks with "known" or "assumed" ligament cracks).

The inspection intervals (i.e., frequency) shall not exceed the intervals calculated using the cumulative damage index model in the subject FaAA report. In addition, inspection method shall be consistent with or equivalent to those identified in the subject FaAA report."

Requested Wording "Whenever diesel generator No. 1 is operated in excess of 4,375 kW for one hour or more, a visual inspection of the right bank cylinder block is to be performed under intense light within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after engine shutdown to verify the absence of stud-to-stud and stud-to-end cracks."

Basis for Change During 1985-1986, NDE was performed on the entire right block top of DG No. I with some cylinder liners removed and on the areas between adjacent stud holes and the stud to liner areas on the left block top of DG No. 1 and both block tops of DG No. 2. No indications were found. At the time of its inspection, the right block top of DG No. 1, which alone has the degraded Widmanstaetten graphite microstructure, had accumulated approximately 900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br /> of operation at loads up to 6600 kW. Regularly scheduled visual inspections after each significant load run will provide continued assurance of absence of cracks.

4375 kW represents one half of the engine load capacity.

(Revi sed)

-5

8. Second Condition of Item No. 5 (Cylinder Blocks)

Present Wording "In addition to inspections specified in the aforementioned FaAA report, blocks with "known" or "assumed ligament cracks" (as defined in the FaAA report) should be inspected at each refueling outage to determine whether or not cracks have initiated on the top surface exposed by the removal of two or more cylinder heads. This process should be repeated over several refueling outages until the entire block top has been inspected.

Liquid-penetrant testing or a similarly sensitive nondestructive testing technique should be used to detect cracking, and eddy current should be used as appropriate to determine the depth of any cracks discovered.

Requested Wording None. Delete this condition.

Basis for Change The entire block tops have been inspected and no cracks found.

This condition is no longer applicable to San Onofre Unit 1.

9. Third Condition of Item No. 5 (Cylinder Blocks)

Present Wording "If inspection reveals cracks in the cylinder blocks between stud holes of adjacent cylinders ("stud-to-stud" cracks) or "stud-to-end" cracks, this condition shall be reported promptly to the NRC staff and the affected engine shall be considered inoperable. The engine shall not be restored to "operable" status until the proposed disposition and/or corrective actions have been approved by the NRC staff."

Requested Wording "If stud-to-stud cracks or stud-to-end cracks are found, these findings are to be reported to the NRC within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The affected engine is to be considered inoperable and is not to be restored to operable status until the proposed disposition and/or corrective actions have been approved by the NRC staff."

Basis for Change "Promptly" is defined as "within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />" to make the reporting requirement better understood and implemented.

(Revi sed)

-6

10.

Item No. 6 (Cylinder Heads)

Present Wording "The following air roll test shall be performed as specified below, except when the plant is already in an Action Statement of Technical Specification 3/4.8.1. "Electrical Power Systems, A.C. Sources":

"The engines shall be rolled over with the airstart system and with the cylinder stopcocks open prior to each planned start, unless that start occurs within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of a shutdown. The engines shall also be rolled over with the airstart system and with the cylinder stopcocks open after 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, but no more than 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after engine shutdown and then rolled over once again approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after each shutdown. (In the event an engine is removed from service for any reason other than the rolling over procedure prior to expiration of the 8-hour or 24-hour periods noted above, that engine need not be rolled over while it is out of service. The licensee shall air roll the engine over with the stopcocks open at the time it is returned to service.)

The origin of any water detected in the cylinder must be determined and any cylinder head which leaks due to a crack shall be replaced. The above air roll test may be discontinued following the first refueling outage subject to the following conditions:

All cylinder heads are Group III heads (i.e., cast after September 1980).

Quality revalidation inspections, as identified in the Design Review/

Quality Revalidation report, have been completed for all cylinder heads.

Group III heads continue to demonstrate leak free performance. This should be confirmed with TDI prior to deleting air roll tests."

Requested Wording None. Delete this condition.

Basis for Change During 1987, all cylinder heads were changed to Group III heads, which have continued to demonstrate leak free performance during the diesel air roll.

Even though SCE will continue these air rolls in the manner recommended by Imo Delaval, air rolls are not a SER requirement with the new Group III heads.

11.

Item No. 7 (Modified Type AF Piston Skirts)

Present Wording "The stud boss attachments of the modified type AF piston skirts shall be inspected with liquid penetrant at each major engine overhaul.

Indications found should also be inspected with eddy

(Revi sed)

-7 current as appropriate. (This license condition may be deleted for individual piston skirts after they have completed 750 hours0.00868 days <br />0.208 hours <br />0.00124 weeks <br />2.85375e-4 months <br /> service at engine loads equaling 4500 kW (+/-5%)).

The following actions shall be performed if the engines are operated in excess of 4500 kW (+5%):

(Specific actions have not yet been developed.)"

Requested Wording None. Delete this condition.

Basis for Change All piston skirts have been changed to Type AE piston skirts, for which no load restrictions are recommended by PNL.

12.

Last Condition of Item No. 8 (Elliot Model 65G and 90G Turbochargers)

Present Wording "The nozzle ring components and inlet guide vanes should be visually inspected at each refueling outage for missing parts or parts showing distress. If such are noted, the entire ring assembry should be replaced."

Requested Wording "The nozzle ring components and inlet guide vanes will be visually inspected on a one turbocharger per refueling outage basis for missing parts or parts showing distress. If such are noted, the entire ring assembly will be replaced."

Basis for Change These changes are consistent with the clarification in Section 2.1.3.24 of the SER that the nozzle ring components of only one turbocharger per refueling be visually inspected, with all the turbochargers being inspected at the major engine overhaul.

13. of SER (San Onofre 1 Proposed Plant-Srecific License Conditions)

Present Wording Refer to SER

(Revi sed)

-8 Requested Wording None. Delete entirely.

Basis for Change Load restrictions and associated contingency inspection requirements stated in Enclosure 2 are no longer applicable because of the recent changeout to type AE piston skirts, proposed requalification of crankshafts to full engine nameplate rating, existing instructions to operators not to exceed allowable load and crankshaft inspections at each refueling as mandated by the Technical Specifications. Any accidental overloading of the diesels is expected to be minimal and subject to immediate corrective action.

IAA:0678n