Letter Sequence Other |
|---|
|
Initiation
- Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request
- Acceptance...
- Supplement, Supplement
Results
Other: 05000206/LER-1981-013, Forwards LER 81-013/99X-0.Detailed Event Analysis Submitted, 05000206/LER-1981-013-99, /99X-0:on 810618,power Operated Relief Valve Controller Opened Twice During Normal Pressure Transient Following Reactor Trip.Caused by Setting Time Constant to Off to Satisfy NUREG-0737,Item II.K.3.9, L-81-029, Forwards Proposed Licensing Exam Schedule for 1981-82 for Reactor & Senior Operator Candidates,Per 810807 Request, L-82-002, Informs That Necessary Procedures Per NUREG-0737,Item I.A.1.3 Re Use of Overtime Required by Generic Ltr 82-12 Will Be Implemented by 821001.Tech Spec Will Not Be Submitted for Review Pending Receipt of Model Tech Specs, ML13308A671, ML13308B064, ML13308B821, ML13308B925, ML13310A775, ML13310A777, ML13310A778, ML13310A826, ML13310A828, ML13310A923, ML13310A926, ML13310B078, ML13310B081, ML13310B120, ML13310B280, ML13310B546, ML13310B619, ML13311B030, ML13316B714, ML13317A133, ML13317A134, ML13317A166, ML13317A190, ML13317A263, ML13317A267, ML13317A289, ML13317A367, ML13317A369, ML13317A377, ML13317A391, ML13317A427, ML13317A450, ML13317A454, ML13317A468, ML13317A478, ML13317A479, ML13317A484, ML13317A488, ML13317A490, ML13317A507, ML13317A512, ML13317A519, ML13317A553, ML13317A567, ML13317A581, ML13317A616... further results
|
MONTHYEARML13333A4221979-10-22022 October 1979
Forwards Responses to NRC post-TMI Requirements Re Design & Analysis,Operations,Rcs High Point Vents,Emergency Preparedness & Instrumentation to Monitor Containment Conditions
Project stage: Other
ML13303A7381979-10-30030 October 1979
Summary of 790927 Meeting W/Utils in San Clemente,Ca Re Emergency Plan Review
Project stage: Request
ML13322A6191979-11-15015 November 1979
Summary of 791108 Telcon W/Util Re Unacceptable Schedule for Implementing Lessons Learned Task Force Items
Project stage: Other
ML13333A4571979-12-14014 December 1979
Forwards Revisions to Util 790913 Commitments Re Compliance w/short-term TMI Lessons Learned Task Force Requirements Per NUREG-0578
Project stage: Other
IR 05000206/19790161980-01-0404 January 1980
IE Insp Rept 50-206/79-16 on 791101-02 & 26.No Noncompliance Noted.Major Areas Inspected:Scope & Methods of Field Insp for IE Bulletin 79-14,repair of Shorted Electrical Buswork & Licensee Design Change Proposal
Project stage: Request
ML13311B0301980-01-21021 January 1980
Discusses Response to NRC 800102 Order to Show Cause Re Implementation of NUREG-0578 Category a Requirements.Will Continue Operation Until 800315.Shutdown on 800131 Would Severely Impact Power Reliability in Pacific Northwest
Project stage: Other
ML13333A4781980-01-23023 January 1980
Advises That Responses to NRC Requesting Info Re Small Break LOCA Guidelines Will Be Submitted by 800228. Bulletin Response Will Be Sent by 800228
Project stage: Other
ML13333A4811980-01-24024 January 1980
Forwards Corrected Page 3 of App 10 to Enclosure a of Re Power Reliability Info.Omitted Info Sent to R Weiner of DOE on 800118
Project stage: Other
ML13333A4831980-01-29029 January 1980
Confirms 800124 & 25 Telcons Re Facility 800126 Shutdown for Implementation of Lessons Learned Task Force Category a short-term Requirements Re Reopening of Containment Isolation Valves
Project stage: Other
ML13308B0641980-01-30030 January 1980
Concludes That Inadequate Justification Exists to Extend Util 800131 Deadline to 800315 for Response to 800102 Order to Show Cause Why All Category a Lessons Learned Requirements Should Not Be Implemented
Project stage: Other
ML19290E8091980-02-0101 February 1980
Denies Request for Shutdown Extension Until 800315 to Complete Category a Requirements W/Available Equipment. Reopening of Containment Isolation Valves Until Further Mods Completed Acceptable
Project stage: Other
ML13333A4981980-02-0808 February 1980
Submits Addl Info Re Commitment Schedule for short-term Lessons Learned Task Force Requirements.Circuitry to Close Auxiliary Feedwater Motor Operated Discharge Valve Will Be Installed During Apr 1980 Refueling Outage
Project stage: Other
ML13333A5031980-02-13013 February 1980
Forwards Justification for RCS Subcooling Setpoint,In Response to NRC 791227 Request.Addl Info Will Be Forwarded in Response to IE Bulletin 79-27 by 800228
Project stage: Other
ML13316B7141980-03-0707 March 1980
Advises NRC of Delay in Responding to Item 4 of as Part of Response to IE Bulletin 79-27.Submittal Rescheduled from 800228 to 800701
Project stage: Other
ML13330A0251980-03-25025 March 1980
Forwards Addl Info for Implementation of TMI short-term Lessons Learned Task Force Requirements.Describes Mods to Backup Nitrogen Pneumatic Supply & Valve Position Indication.Drawing Available in Central Files Only
Project stage: Other
ML13330A0271980-03-28028 March 1980
Responds to NRC 800117 Request for Review of Draft Evaluation of SEP Topic XV-20, Radiological Consequences of Fuel Damaging Accidents,(Inside & Outside Containment). Review Confirms Facts as Correct
Project stage: Request
ML13330A0321980-04-11011 April 1980
Confirms 800410 Telcons W/Regulatory Personnel Re Implementation of Several Category a TMI Lessons Learned Task Force Requirements Described in
Project stage: Other
IR 05000206/19800041980-04-11011 April 1980
IE Insp Rept 50-206/80-04 on 800128-0229.Noncompliance Noted:Failure to Rept Reactor Protection Sys Setpoints Less Conservative than Those Established by Tech Specs & Use of Nonstandard Fitting
Project stage: Request
ML13331B3711980-05-0707 May 1980
Ro:On 800506,during Refueling Operations,After Lowering of Reactor Internal Instrumentation Package,Incore Instrumentation Package for Thimble Location D-7 Found Bent Outward.Caused by No Provision for Thimble Passage to Core
Project stage: Request
ML13330A0521980-05-22022 May 1980
Discusses Open Items Re Implementation of Category a Lessons Learned Task Force Requirements Per NRC 800502 Request.Open Items Involve Instrumentation for Inadequate Core Cooling, post-accident Sampling & Reactor Cooling Sys Venting
Project stage: Other
ML13330A0621980-06-13013 June 1980
Discusses Completed Review of NRC Forwarding Five Addl Items Resulting from post-TMI Reviews.Forwards Commitments to Meet Implementation Requirements for Items 1-5
Project stage: Other
ML13319A2131980-07-0909 July 1980
Forwards Post-Accident Sampling Sys,Capabilities & Description, & Drawings,In Response to Open Item Identified in NRC Re Implementation of TMI Lessons Learned Requirements.Drawings Available in Central Files Only
Project stage: Other
IR 05000206/19800201980-07-0909 July 1980
IE Insp Rept 50-206/80-20 on 800616-19.No Noncompliance Noted.Major Areas Inspected:Major Maint,Major Surveillance, IE Bulletin & Circular Followup & Independent Insp Effort
Project stage: Request
ML13322A7711980-07-0909 July 1980
Post-Accident Sampling Sys,Capabilities & Description
Project stage: Other
ML13302A4691980-09-12012 September 1980
Forwards Amend 20 to Fsar.Amend Contains Responses to NUREG- 0660 & NUREG-0694, TMI-Related Requirements for New Ols
Project stage: Request
ML13322A9461980-09-12012 September 1980
Notifies That Actions Required in NRC Re License Amend Application Concerning Implementation of TMI Lessons Learned Requirements Cannot Be Accomplished by 800912. License Amend Application Will Be Submitted by 810116
Project stage: Other
ML13330A1321980-10-0909 October 1980
Notifies That Date for Submittal of Info Re Design Details for Reactor Coolant Vents & Addl Info for Main Steam Line Piping Integrity Evaluation Will Be Submitted 801101 & 1201,respectively
Project stage: Other
ML13330A1351980-10-15015 October 1980
Provides Plans,Schedules & Commitments to Meet Interim Criteria for Shift Staffing & Administrative Controls,In Response to NRC 800731 Request.Full Compliance W/Criteria Will Be Achieved No Later than 820701
Project stage: Other
ML13316A5161980-10-31031 October 1980
Environ Qualification of Electrical Equipment
Project stage: Request
ML13330A1581980-12-23023 December 1980
Advises That Response to NRC Requesting Confirmation for Implementation Dates of TMI-related Items Will Be Submitted by 810105
Project stage: Other
ML13308B8211980-12-30030 December 1980
Submits Addl Info Re Description of Shift Technical Advisor Training Program & Plans for Requalification Training Per 791031 Request
Project stage: Other
ML13330A1661981-01-0707 January 1981
Notifies That License Amend Application to Incorporate Applicable Tech Specs for Implementing TMI-2 Lessons Learned Category a Items Will Be Submitted by 810401
Project stage: Request
ML13308A6711981-01-13013 January 1981
Advises That Licensee Inadvertently Omitted Info from Re Plans for Implementation of Action Item II.K.3.25 in NUREG-0737 Re Effect of Loss of Ac Power on Pump Seals. Evaluation Will Be Submitted by 820101
Project stage: Other
ML13330A1911981-01-14014 January 1981
Informs That Radiochemical & Chemical Analysis Mods Promised in Util No Longer Necessary.Due to Other TMI Recommendations,Samples Can Be Analyzed Outside Lab.Cart Mounted Iodine Sampler W/Single Channel Analyzer to Be Used
Project stage: Other
ML14135A0051981-01-23023 January 1981
High Radiation Sampling Station General Piping Arrangement Plan
Project stage: Other
ML13330A1931981-02-0202 February 1981
Forwards Application for Amend 96 of License DPR-13
Project stage: Request
IR 05000206/19810041981-02-25025 February 1981
IE Insp Rept 50-206/81-04 on 801229-810130.No Noncompliance Noted.Major Areas Inspected:Followup on Systematic Appraisal of Licensee Performance & Allegation by Contractor Employee
Project stage: Request
ML13330A2411981-03-0606 March 1981
Responds to IE Bulletin 80-04, Analysis of PWR Main Steam Line Break W/Continued Feedwater Addition. Auxiliary Feedwater Sys Automatic Initiation Will Occur on Low Steam Generator Level W/Setpoint at 5% of Narrow Range Instrument
Project stage: Other
ML13330A2661981-03-17017 March 1981
Forwards Listing Containing Brief Description of Design Changes Completed During 1980 Per 10CFR50.59b & Rept on Challenges to Relief & Safety Valves Per NUREG-0578
Project stage: Other
ML13330A2671981-03-18018 March 1981
Advises That post-accident Sampling Sys,Described in Licensee ,Will Not Include Capability to Perform Chloride Analysis,Per NUREG-0737 & NUREG-0578.Chloride Analyses Using Dilute Samples Are Inaccurate
Project stage: Other
ML13330A2911981-04-13013 April 1981
Responds to NRC 801031 Request for Clarification of NUREG-0737 Requirements & Confirmation of Implementation Date.Rept by NUS Corp, Control Room Habitability Evaluation San Onofre Generating Station,Unit 1 Encl
Project stage: Request
ML13302B0341981-04-13013 April 1981
Summary of 810310 Meeting W/Utils in Bethesda,Md Re Explosion Hazards.Attendance List & Applicant Handouts Encl
Project stage: Request
ML13331A0741981-04-17017 April 1981
Requests That NRC Finish Review of Util Compliance W/Ie Bulletin 79-06C, Nuclear Incident at TMI - Suppl. Review Completion Needed for Util to Complete Design Change to Assure Automatic Tripping of Reactor Coolant Pumps
Project stage: Other
ML13330A2991981-04-20020 April 1981
Forwards Response to NUREG-0737,Item II.K.3.17 Re ECCS Equipment Outages.Also Forwards Analysis of Probability of Toxic Gas Hazard for San Onofre Nuclear Generating Station as Result of Truck Accidents Near Plant
Project stage: Other
ML13317A6101981-05-0707 May 1981
Forwards Addl Info Re SEP Topic XV-16, Radiological Consequences of Failure of Small Lines Carrying Primary Coolant Outside Containment, Per 801215 & 810319 Requests
Project stage: Request
ML13317A6161981-05-12012 May 1981
Advises That TMI Action Plan Item II.K.3.9 Was Not Completed by 810101.Facility Has Been Shut Down Since Apr 1980.Item Will Be Completed Prior to Restart.Also Lists Completion Schedules for Items II.D.3,II.E.4.2.,II.G.1 & III.D.3.3
Project stage: Other
ML13317A6271981-06-0808 June 1981
Submits Results of Evaluation of Containment post-accident Pressure Reanalysis on Operational Limits,In Response to TMI Action Plan Item II.E.4.2(5).Peak post-accident Pressure & Temp in 770119 Analysis Is Still Applicable
Project stage: Other
ML20196A6141981-06-15015 June 1981
IE Review & Evaluation of Licensee Implementation of TMI Action Plan Requirement 1.C.5, `Procedures for Feedback of Operating Experience to Plant Staff
Project stage: Other
ML20196A6061981-06-15015 June 1981
IE Review & Evaluation of Licensee Conformance W/Tmi Action Plan Requirements 1.A.1.3, `Shift Manning Part 1,Limit Overtime
Project stage: Other
ML13317A6371981-06-17017 June 1981
Advises That Effluent Monitoring Sys,Per NUREG-0737,Item II.F.1 Will Not Be Completed Prior to Startup,As Remote Readout Gm Detector Has Been Removed.Interim Requirements of NUREG-0578 Will Be Met Per
Project stage: Other
1980-04-11
[Table View] |
Text
PWR SAFETY AND RELIEF VALVE TEST PROGRAM, PORV BLOCK VALVE ADEQUACY REPORT FOR SOUTHERN CALIFORNIA EDISON SAN ONOFRE UNIT 1 Revison 2 SEPTEMBER, 1983 Prepared by:
R. M Grayso Verified. by:
Approved by:
H. Sepp, M er Pump and Valve Engineering 8311280372 831117 PDR ADOCK 05000206 P
PDR Westinghouse Electric Corporation Nuclear Energy Systems P.O. Box 355 Pittsburgh, PA 15230 0901E:1
1.0 INTRODUCTIO-N NUREG-0737, Item II.D.l.B requires PWR utilities to demonstrate that their block valves function properly over expected operating and accident conditions. This-demonstration is to be supported by test data.
During a meeting between the NRC st-aff and utility representatives on July 17, 1981, agreement was reached regarding resolution of the above.requirement.
Details of the uti'lity position on block valve testing is contained in reference 1.
In response to NUREG-0737, Item II.D.i.B, Reference 2 transmitted to the NRC, "EPRI PWR7Safety and Relief Valve Test Program, PWR Safety and Relief Valve Test Program, PORV Block Valve Information Package",,May 1982 (Reference 3).
Included in thi.s submittal was:
0 A description of block valves. used in or planned-for use in PWR plants.
An EPRL report entitled "EPRI/Marshall Electrfc Motor Operated Valve (Block Valve) Interim Test Data Report, May 31, 1982.
o A Westinghouse report entitled-EPRI Summary Report; Westinghouse:Gate Valve Closure Test.ingProgram, March 31, 1982.
Reference 2 also states that.. PWR utilities believe sufficient evidence (supported by test data) is available-to demonstrate block valve "operability". Response to the NUREG requirement was to be fulfilled.by submittal of the-above mentioned document package and a.
separate plant-specific evaluation of block valve operability.
This document provides the plant-specific response and evaluation of the Block Valve Test program for Southern California Edison San Onofre Unit 1.
090TE:1 2
2.0 BLOCK VALVE DESIGN INFORMATION The block valves installed at San Onofre Unit 1 are 2-Inch, 1500 lb., Fail Open Darling Double Disc Gate valves which utilize a BS&B Air Diaphragm Operator.
During the EPRI testing at Marshall Steam-Station Test Facility, a 3-inch 1540 lb.. Anchor-Darling Motor Operated Double Disc Gate valve was tested.
Results of these-tests were used as a bassis in determining-the adequacy of the SCE Block. Valves.
For-comparison, a descriptionr of the Anchor-Darling-test valve and the SCE Block Valve is provided-- in Table 2-1.
Table 2-2 provides the' SCE Block Valve Operator Information.
3.0
SUMMARY
OF BLOCK-VALVE TEST RESULTS Results of the Anchor-Darling block valve tests conducted at Marshall Test Facility are contained in Section 3-. of' Referencei-(3)
Theva-lves,, although different ins avre similar operating, and design conditions and employ similar body, seat surface and packing materials.
The smaller SCE. BTock Valve requires. Tess operating force as can be seen by the load comparison in Table:2-l.
Both valves are of the-parallel disc design and have the same internal contour and sealing.mechanism. It is this similarity which permits extrapolation of the EPRI test results to the SCE Valve.
Evaluation testing-of the Anchor/Darling test va]lvewas performed on September 25-, 1980, with the Fisher PORVmounted downstream of the test.valve.
The valve was cycled 21 times and the results of these tests are summarized in Table 3.4-3 of Reference (3)-, Evaluation Test Data.
Prior to these evaluation tests, pretest calibration and checkout activities were conducted. At this time operating torque requirements were evaluated and different-valve operators were used as part of the checkout evaluation.
0901E:1 3
TABLE 2-1 Comparison of EPRI Test Valve and SCE Block Valve EPRI SCE BLOCK PARAMETER TEST VALVE VALVE Valve Description 3"-1540# Gate 2"1500# Gate Drawing No..
93-15268 10529 Operating/Design Conditions Pressure (psig).
2405 2485 Temperature. (oF) 650 680 Differential Press.. (psi) 2405 2485 Flow Rate (lbs/hr) 176,000 Material Body SA35T1-CF8M A35T-CF8M Seat. Surface teite No. 66
- Packing, 187' Crane 187 Valve Design, Mean Seat Dia/Area (in/n 2 7/ 6.49 1-7/8/2.76 Steam Dia/Area (in/in )
1-1/4/1.23 3/4 /.442 Stroke (in) 3-1/2 2-1/2 Packing Rings 4 Rings-Double 12 Rings Required Open force (lb)
Seat Load:
6458 2838 Stem UnbaTance (2958')
(1098)
Packing Drag 3000 1800 Total Open Force (lb.)
6500 3540 Required Close Force S(1b.)
Seat Load 8442 3714 Stem Unbalance 2958 1098 Packing Drag 3000 1800 Total Close Force (lb.)
14400 6612
TABLE 2-2 SCE BLOCK VALVE OPERATOR INFORMATION Actuator Manf.
BS& B Type 70-13-1-0 Style Pneumatic Diaphram Operator Diaphram Size, 140. sq.- in..
Air Supply, 80 psig. (Nom.)
0901E: 1 5
The valve was tested with several modified and new operators as detailed in reference (3).
With the modified Rotork 16-NA1 operator and the 30-NAl operator, the valve closed completely against full flow.
3.1 Results. of the Evaluation Tests The Anchor/Darling Block Valve was cycled a total of 21 times during the evaluation test program with a-torque setting of 4.5.
Results of the evaluation tests-: are summarized in Table 3.4-3, Evaluation Test Data of reference (3).
Summarizing, the-valve fully opened and closed for each of the 21 evaluation test cycles.
Initial; upstream pressure, ranged from 2215 psig to 2260 psig,. valve stroke times ranged-from 5.9-to 6.6-seconds,, and, seat leakage ranged from 0.0 to 0.066 gpm after the evaluation tests.. The operating conditions approximately simulated those of the SCE Block Valve and the post test seat leakage is sma1 enough to consider the-valve to have performed it's blockingifunction satisfactorily.
4.0
SUMMARY
OFANCHOR/DARLING BLOCK A VALVE DESIGN ADEQUACY REPORT Since the Anchor/Darling Block valve-tested by EPRL has some design differences, compared to. the. SCE Block: Valve and the EPRLvalve was tested with:
an electric motor operator while theSCE valve employs an air operator, Anchor/Darling was requested to prepare an evaluation of the two valves. This evaluation was.to compare-the designs, review the EPRI test data and recommend any necessary modifications for-the SCE Block Valve in order to meet the specification requirements.- Details of the-study appear-in Anchor/Darling Report"No. E3050-00Treference (4). Findings of the study will be summarized herein.
0901E:l 6
The EPRI Block Valve testing was used as a basis in determining the adequacy of the SCE Block Valve. The SCE Valve design was examined for the following characteristics:
- 1. Design comparison with the EPRI Test Valve
- 2. Opening and-closing resistance forces
- 3. Available actuator thrusts
- 4. Structural adequacy
- 5. Isolation characteristics 4.1 Design Comparison The SCE Block Valve is a 2-inch 1500 lb. doublel disc gate valve using a BS&B fail open, direct,. type 70-13-1-D pneumatic diaphragm operator. The design of the 3-inch 1540 lb. double disc motor operated:EPRI Test Valve is similar to the SCE. Valve having, the same internal contour and sealing mechanism. This similarity allows extrapolation of the-EPRI test results to the SCE Valve.
Differences, in seat diameter, stem size and design pressures were taken into account when determining valve resistance-forces for the SCE valve..
4.2 Valve:Resistance Forces.:.,
Forces resisting valve opening.and closing may be attributed to seat load, pressure unbalance on the valve stem and stem packing drag. Seat. and packing drag are frictional forces resisting motion, while stem unbalance assists valve opening.
These resistance forces were. calculated. for. the SCE valve using the EPRI test.
results, and adjusting values-to account fbr the design differences between the EPRI and SCE valves. A summary of the resulting forces is presented in Table 2-1.
0901E:1 7
4.3 Actuator Output Force The actuator used to operate the SCE Block valve is a pneumatic diaphragm actuator using an internal coil spring to provide opening force and air pressure to provide the.:closing forces.
Assuming the spring rate is 1020 lbs.
per inch, and: the spring is-initiallycompressed two (2) inches, the actuator can provide the following output forces:
Valve Full' Open: - Spring Rate x Compression U020' lbinch x 2 inch =- 2040 lbs...
Vave-FuTT Close: - Spring Rate x' (Compression. + Stroke) 1020 lb/inch x (2 inch + 2.5 inch) =-4590 lbs.
Available actuator forces to close, the valve is a function of the input air pressure and internal spring forces. Using 85 psig air supply, the actuator can provide the following output forces:
Valve Full. Open:,-
Air-Pressure x7Diaphragm Area. - Spring Load 85 psig x 140 in
- 2040 lb 9860 lbs..
Valve Full Closed: --Same as Full Open 85' psig x 140 in2 - 4590 lbs =710 lbs.
This data is plotted along with the valve resistance forces as a function of stem position-and is presented as figure 4-1.
As can be seen the SCE air operator can provide the required thrust to open and close the SCE Block Valve assuming 85 psig air avaflability and a 1020 lbs. per inch spring..
4.4 Valve Structural Analysis A structural analysis was-provided by-Anchor/Darling to. review stresses at.
critical sections of the valve.
0901E:1 8
The analysis verifies that operating loads will not structurally damage the valve with regard to operability or pressure integrity. The actuator is designed to withstand its maximum rated thrust of 14000 pounds which is 190%
of that required to close the SCE Block Valve.
4.5 Isolation Characteristics The sellite seating surfaces of the EPRI test valve were galled after cycle testing at the Marshal l Steam Station. It-is expected that the SCE Block valve would exhibit. the same: wear when-exposed to: similar conditions.
A solution to this. problem has not yet been'determined. Anchor/Darling is expected to conduct additional tests to define the ciuse of the problem and propose a resolution. The wear observed will result in seat leakage as noted during the EPRI tests, but should not effect valve operation as noted by the 21 successful evaluation, test cycles.
5.0
SUMMARY
AND CONCLUSIONS, The design of: the SCE Block Valve is simlTar to the,esign of the EPRI' test valve and the-results of the EPRI' te st can be used as a basis for evalution of e.The fi open. d.iaphragm actuator of the-SCE BLock Valve is capable of opening and closing the valve against resistance forces determined using the EPRI test results.
0901E:l 9
versus /avi Dai os~tc c
0t zc
~ie 12.01 (1,00 ps i,-
A~r Cio. Cyc' A Ac.
a o Cuzzu-t I Ai c
- a. c 6.i I
<~ <
2_
T s s a c
-- C a 3r 0~~en Cyc e
p ; g ~
1.0 1.0 VALVE STM~s::~,~0E'N
-*a or in e d cr Anch~or,Dariina Reoort,_Refe'rence(4
Investigations made by SCE in response to the Anchor/Darling study revealed the actuators installed at SCE incorporated a nested spring arrangement with a spring rate of approximately 1850 lb/in. Since an actuator with a 1020 lb/in.
spring can provide adequate operating characteristics with 85 psig air supply according to the valve manufacturers. SCE is considering replacing the nested.
spring arrangement with a 1020 lb/in. spring per the Anchor/Darling study.
Anchor/Darling" is still reviewingsthe-galling problems noted in the EPRI Test.. SCE must, monitor the A/D investigations. and. give consideration to incorporating any Anchor/Darling.recommendations when they become available.
In conclusion the, SCE Block Valve is-capable of completing its intended function to open and close against the system flow conditions as tested by EPRI during the Marshall Tests.
0901E:
5.0 REFERENCES
- 1.
Letter from R. C. Youngdahl, Consumers Power, to H. Denton, NRC, dated July 1, 1981.
- 2.
Letter from R. C. Youngdahl,, Consumers: Power, to H. Denton, NRD, dated June 1, 1982.
"EPRI PWR Safety and Relief Valver Test. Program PORV Block Valve Information Package", dated May,. 1982.
- 4.
Anchor/Darling. Report "Design Adequacy Report of South California Edison Company Block Valve 2" - S350-WDD Series 1500 Stainless Steel Double Disc Gate Valve", dated 5-6-83.
0901E: 1 12'
