|
---|
Category:Letter
MONTHYEARML23180A1512023-06-29029 June 2023 LLC, Request for Exemption to the Reporting Requirements of 10 CFR 50.46(a)(3) ML21102A3072021-04-15015 April 2021 OEDO-21-00155 - Lessons-Learned from the Design Certification Review of the NuScale Power, LLC, Small Modular Reactor ML21050A4312021-02-19019 February 2021 LLC - Lessons-Learned from the Design Certification Review of the NuScale Power, LLC Small Modular Reactor ML20247J5642020-09-11011 September 2020 Standard Design Approval for the NuScale Power Plant Based on the NuScale 600 Standard Plant Design Certification Application ML20231A8042020-08-28028 August 2020 Final Safety Evaluation Report for the NuScale Standard Plant Design ML20224A4602020-08-25025 August 2020 OEDO-20-00292-Response to the Advisory Committee on Reactor Safeguards Letter on NuScale Power, LLC, Report on the Safety Aspects of the NuScale Small Modular Reactor ML20231A5982020-08-25025 August 2020 OEDO-20-00285_NuScale Area of Focus - Boron Redistribution ML20210M8902020-07-29029 July 2020 Area of Focus - Boron Redistribution ML20195A5872020-07-13013 July 2020 LLC - Submittal of Draft Operator Licensing and Examination Standard for NuScale Small Modular Reactors ML20195C7662020-07-13013 July 2020 LLC Request for Standard Design Approval Based on the NuScale Standard Plant Design Certification Application ML20192A3262020-07-10010 July 2020 LLC, Submittal of Environmental Report: Revision Status ML20198M3932020-07-0202 July 2020 LLC Submittal of Revised Packing Slip for Submittal of the NuScale Standard Plant Design Certification Application, Revision 4.1, Dated June 19, 2020 ML20174A3472020-07-0101 July 2020 OEDO-20-00220 - Area of Focus - Probabilistic Risk Assessment and Emergency Core Cooling System Valve Performance ML20184A2872020-07-0101 July 2020 LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topic - Boron Redistribution and General Design Criterion 33, PM-0720-70785, Revision 0 ML20181A4322020-06-22022 June 2020 Final SER for NuScale TR-0516-49416 NON-Loss-of-Coolant Analysis Model, Rev 3 (Letter) ML20181A2702020-06-22022 June 2020 Final SER for NuScale TR-0516-49422 Loss-of-Coolant Analysis Model, Rev 2 (Letter) ML20198M3922020-06-19019 June 2020 LLC - Submittal of the NuScale Standard Plant Design Certification Application, Revision 4.1 ML20171A7312020-06-19019 June 2020 LLC, Submittal of Riser Flow Hole Methodology and Associated Changes to Final Safety Analysis Report Incorporating Its Use ML20157A2232020-06-0303 June 2020 Letter to NuScale Requesting -A for TR-0716-50350 ML20150C5172020-05-29029 May 2020 LLC Submittal of Presentation Materials Entitled NRC Public Meeting Presentation: Boron Redistribution and Associated Design and DCA Changes, PM-0620-70336, Revision 0 ML20150E1772020-05-29029 May 2020 LLC - Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topic - Extended Dhrs Operation and RCS Boron Redistribution (Closed Session), PM-0620-70243, Revision 0 ML20150C8812020-05-29029 May 2020 LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topic - Boron Redistribution and Associated Design and DCA Changes, PM-0620-70244, Revision 0 ML20149M1192020-05-28028 May 2020 LLC Summary of Impacts to Erai 8930 Response and Discussion on the Exemption from General Design Criterion 33 ML20141L8082020-05-20020 May 2020 LLC Submittal of Containment Response Analysis Methodology Technical Report, TR-0516-49084, Revision 3 ML20141N0122020-05-20020 May 2020 LLC Submittal of Changes to Final Safety Analysis Report, Section 6.2, Containment Systems, Section 6.3, Emergency Core Cooling System, and Technical Report TR-0516-49084, Containment Response Analysis Methodology Technical Report ML20141M7642020-05-20020 May 2020 LLC Submittal of Nuclear Steam Supply System Advanced Sensor Technical Report, TR-0316-22048, Revision 3 ML20141L7872020-05-20020 May 2020 LLC, Submittal of Second Updates to Standard Plant Design Certification Application, Revision 4 ML20141L8162020-05-20020 May 2020 LLC, Submittal of Long-Term Cooling Methodology, TR-0916-51299, Revision 3 ML20141M1142020-05-20020 May 2020 LLC Submittal of NuScale Instrument Setpoint Methodology Technical Report, TR-0616-49121, Revision 3 ML20141L8042020-05-20020 May 2020 LLC Submittal of Technical Specifications Regulatory Conformance and Development, TR-1116-52011, Revision 4 ML20128J3162020-05-18018 May 2020 OEDO-20-00167 - Response to the ACRS Letter on Combustible Gas Monitoring ML20133K0882020-05-12012 May 2020 LLC, Submittal of Presentation Materials Entitled Public Meeting Presentation: Topic - Emergency Core Cooling System (ECCS) Boron Distribution (Closed Session), PM-0420-69512, Revision 0 ML20133J9142020-05-11011 May 2020 LLC Submittal of Presentation Materials Entitled Public Meeting Presentation: Topic - Emergency Core Cooling System (ECCS) Boron Distribution, PM-0420-69511, Revision 0 ML20112F4552020-05-0101 May 2020 LLC, Design Certification Application Phases 5 and 6 Review Status ML20107F8492020-05-0101 May 2020 OEDO-2000140 - NuScale Area of Focus - Helical Tube Steam Generator Design ML20104A0792020-04-27027 April 2020 OEDO-20-00115 - Safety Evaluation Report for Topical Report TR-0516-49416, Revision 2, Non-Loss-of-Coolant Accident Analysis Methodology ML20099H0802020-04-0808 April 2020 LLC - Submittal of Presentation Materials Entitled NRC Public Meeting: Revisions to Nuscale'S EPZ Sizing Methodology Topical Report, PM-0420-69598, Revision 0 ML20098G2372020-04-0707 April 2020 Nuscale Power, LLC Submittal of Remaining Closure Items for the Emergency Core Cooling System Valve Failure Mode Effects Analysis Audit Items ML20097F1922020-04-0606 April 2020 Nuscale Power, LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: Nuscale Topic - Hydrogen/Oxygen Monitoring, PM-0420-69518, Revision 0 ML20094H6742020-04-0303 April 2020 LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation NuScale Topic-Probabilistic Risk Assessment with a Focus on Emergency Core Cooling System Analysis PM-0420-69559, Revision 0 ML20092L8992020-04-0101 April 2020 LLC - Submittal of Updates to Standard Plant Design Certification Application, Revision 4 ML20072M6682020-03-30030 March 2020 Response to NuScale Letter Dated February 24, 2020, on Planned SDA Application Content ML20072H3332020-03-0909 March 2020 LLC - Submittal of Presentation Materials Entitled Public Meeting Presentation: Topic - Emergency Core Cooling System (ECCS) Boron Distribution, PM-0320-69218, Revision 0 ML20057D9002020-03-0606 March 2020 Submittal of Errata to Final SE for NuScale Power, LLC TR-1010-859-NP-A, Quality Assurance Program Description for the NuScale Power Plant ML20062F7262020-03-0505 March 2020 Request for Withholding Information from Public Disclosure for Nuscale Power, LLC Letter Public ML20069A1572020-03-0404 March 2020 LLC - Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topical Report-Rod Ejection Accident Methodology, PM-0320-69146, Revision 0 ML20069A1772020-03-0404 March 2020 LLC - Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topical Report-Non-Loss-of-Coolant Accident, PM-0320-69141, Revision 0 ML20069A9632020-03-0404 March 2020 LLC Submittal of Presentation Materials Entitled ACRS Full Committee Presentation: NuScale Topical Report, Loss-of-Coolant Accident Evaluation Model, PM-0320-69138, Revision 0 ML20066G2802020-03-0303 March 2020 LLC, Submittal of Presentation Materials Entitled ACRS Subcommittee Presentation: NuScale Topic - Hydrogen Monitoring, PM-0220-69071, Revision 0 ML20066G2882020-02-28028 February 2020 LLC Submittal of Presentation Materials Titled ACRS Full Committee Presentation: NuScale - Steam Generator Design (Closed Session), PM-0220-69053, Revision 0 2023-06-29
[Table view] Category:Response to Request for Additional Information (RAI)
MONTHYEARRAIO-0420-69855, LLC, Submittal of Corrected Response to NRC Request for Additional Information No. 284 (Erai No. 9225) on the NuScale Design Certification2020-04-30030 April 2020 LLC, Submittal of Corrected Response to NRC Request for Additional Information No. 284 (Erai No. 9225) on the NuScale Design Certification ML19332A1202019-11-27027 November 2019 LLC Supplemental Response to NRC Request for Additional Information No. 484 (Erai No. 8930) on the NuScale Design Certification Application ML19304B4712019-10-31031 October 2019 LLC Supplemental Response to NRC Request for Additional Information No. 466 (Erai No. 9482) on the NuScale Design Certification Application ML19296D8052019-10-23023 October 2019 LLC Response to NRC Request for Additional Information No. 526 (Erai No. 9719) on the NuScale Design Certification Application ML19283E5302019-10-10010 October 2019 LLC Supplemental Response to NRC Request for Additional Information No. 522 (Erai No. 9681) on the NuScale Design Certification Application ML19260G7352019-10-0707 October 2019 Summary of Public Meeting with NuScale to Discuss Response to RAI 9681 ML19266A5872019-09-23023 September 2019 LLC Supplemental Response to NRC Request for Additional Information No. 518 (Erai No. 9659) on the NuScale Design Certification Application ML19262G9742019-09-19019 September 2019 LLC - Submittal of Changes to Final Safety Analysis Report, Tier 1, Section 3.11, Reactor Building and Section 3.13, Control Building, and Tier 2, Section 3.8.4, Design of Category I Structure and Section 14.3, Certified ... ML19262G5762019-09-19019 September 2019 LLC - Submittal of Changes to Final Safety Analysis Report, Section 14.2, Initial Plant Test Program, Table 14.2-2, Pool Cleanup Systems Test #2, and Table 14.2-50, Module Assembly Equipment Test #50 ML19259B8102019-09-16016 September 2019 LLC Supplemental Response to NRC Request for Additional Information No. 205 (Erai No. 9044) on the NuScale Design Certification Application ML19259A0922019-09-16016 September 2019 LLC Response to NRC Request for Additional Information No. 525 (Erai No. 9705) on the NuScale Design Certification Application ML19238A3722019-08-26026 August 2019 LLC Supplemental Response to NRC Request for Additional Information No. 197 (Erai No. 9051) on the NuScale Design Certification Application ML19238A3662019-08-23023 August 2019 LLC - Response to NRC Request for Additional Information No. 523 (Erai No. 9682) on the NuScale Design Certification Application ML19215A0032019-08-0202 August 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 202 (Erai No. 8911) on the NuScale Design Certification Application ML19215A0062019-08-0202 August 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 441 (Erai No. 9485) on the NuScale Design Certification Application ML19212A7622019-07-31031 July 2019 LLC Response to NRC Request for Additional Information No. 523 (Erai No. 9682) on the NuScale Design Certification Application ML19212A3752019-07-31031 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 483 (Erai No. 9516) on the NuScale Design Certification Application ML19212A7992019-07-31031 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 427 (Erai No. 9408) on the NuScale Design Certification Application ML19212A6892019-07-31031 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 205 (Erai No. 9044) on the NuScale Design Certification Application ML19210D1592019-07-29029 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 401 (Erai No. 9447) on the NuScale Design Certification Application ML19210D7342019-07-29029 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 520 (Erai No. 9642) on the NuScale Design Certification Application ML19210E1462019-07-29029 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 197 (Erai No. 9051) on the NuScale Design Certification Application ML19207B3812019-07-26026 July 2019 LLC - Response to NRC Request for Additional Information No. 427 (Erai No. 9408) on the NuScale Design Certification Application ML19207A5342019-07-26026 July 2019 LLC - Response to NRC Request for Additional Information No. 523 (Erai No. 9682) on the NuScale Design Certification Application ML19207B8522019-07-25025 July 2019 LLC Response to NRC Request for Additional Information No. 194 (Erai No. 8884) on the NuScale Design Certification Application ML19203A3152019-07-22022 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 325 (Erai No. 9268) on the NuScale Design Certification Application ML19203A3212019-07-22022 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 333 (Erai No. 9282) on the NuScale Design Certification Application ML19203A3092019-07-22022 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 54 (Erai No. 8837) on the NuScale Design Certification Application ML19203A3422019-07-22022 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 154 (Erai No. 8938) on the NuScale Design Certification Application ML19200A2482019-07-19019 July 2019 LLC Response to NRC Request for Additional Information No. 522 (Erai No. 9681) on the NuScale Design Certification Application ML19200A2082019-07-19019 July 2019 LLC - Response to NRC Request for Additional Information No. 524 (Erai No. 9691) on the NuScale Design Certification Application ML19199A1172019-07-18018 July 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 484 (Erai No. 8930) on the NuScale Design Certification Application ML19198A3252019-07-17017 July 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 249 (Erai No. 9135) on the NuScale Design Certification Application ML19196A3682019-07-15015 July 2019 LLC Response to NRC Request for Additional Information No. 516 (Erai No. 9647) on the NuScale Design Certification Application ML19191A2202019-07-10010 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 197 (Erai No. 9051) on the NuScale Design Certification Application ML19184A6152019-07-0303 July 2019 LLC Supplemental Response to NRC Request for Additional Information No. 386 (Erai No. 9316) on the NuScale Design Certification Application ML19176A5802019-06-25025 June 2019 LLC Supplemental Response to NRC Request for Additional Information No. 232 (Erai No. 9113) on the NuScale Design Certification Application ML19170A3702019-06-19019 June 2019 LLC Supplemental Response to NRC Request for Additional Information No. 232 (Erai No. 9113) on the NuScale Design Certification Application ML19168A2442019-06-17017 June 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 325 (Erai No. 9268) on the NuScale Design Certification Application ML19164A1452019-06-13013 June 2019 LLC - Submittal of Containment Response Analysis Methodology Technical Report, TR-0516 -49 08 4, Revision 1 ML19157A3262019-06-0606 June 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 232 (Erai No. 9113) on the NuScale Design Certification Application ML19154A6222019-06-0303 June 2019 LLC Supplemental Response to NRC Request for Additional Information No. 202 (Erai No. 8911) on the NuScale Design Certification Application ML19154A6052019-06-0303 June 2019 LLC Response to NRC Request for Additional Information No. 514 (Erai No. 9645) on the NuScale Design Certification Application ML19151A8372019-05-31031 May 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 377 (Erai No. 9380) on the NuScale Design Certification Application ML19140A4592019-05-20020 May 2019 LLC Supplemental Response to NRC Request for Additional Information No. 401 (Erai No. 9447) on the NuScale Design Certification Application ML19137A2902019-05-17017 May 2019 LLC Supplemental Response to NRC Request for Additional Information No. 156 (Erai No. 9031) on the NuScale Design Certification Application ML19137A2872019-05-15015 May 2019 LLC Response to NRC Request for Additional Information No. 519 (Erai No. 9656) on the NuScale Design Certification Application ML19126A2942019-05-0606 May 2019 LLC Supplemental Response to NRC Request for Additional Information No. 26 (Erai No. 8840) on the NuScale Design Certification Application ML19122A5092019-05-0202 May 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 494 (Erai No. 9548)on the Design Certification Application ML19121A6002019-05-0101 May 2019 LLC - Supplemental Response to NRC Request for Additional Information No. 202 (Erai No. 8911) on Design Certification Application 2020-04-30
[Table view] |
Text
RAIO-1217-57850 December 21, 2017 Docket No.52-048 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738
SUBJECT:
NuScale Power, LLC Supplemental Response to NRC Request for Additional Information No. 154 (eRAI No. 8938) on the NuScale Design Certification Application
REFERENCES:
- 1. U.S. Nuclear Regulatory Commission, "Request for Additional Information No. 154 (eRAI No. 8938)," dated August 07, 2017
- 2. NuScale Power, LLC Response to NRC "Request for Additional Information No. 154 (eRAI No.8938)," dated October 05, 2017 The purpose of this letter is to provide the NuScale Power, LLC (NuScale) supplemental response to the referenced NRC Request for Additional Information (RAI).
The Enclosure to this letter contains NuScale's supplemental response to the following RAI Questions from NRC eRAI No. 8938:
03.12-2 03.12-3 This letter and the enclosed response make no new regulatory commitments and no revisions to
any existing regulatory commitments.
If you have any questions on this response, please contact Marty Bryan at 541-452-7172 or at
mbryan@nuscalepower.com.
Sincerely, Zackary W. Rad Director, Regulatory Affairs NuScale Power, LLC Distribution: Gregory Cranston, NRC, OWFN-8G9A Samuel Lee, NRC, OWFN-8G9A Marieliz Vera, NRC, OWFN-8G9A : NuScale Supplemental Response to NRC Request for Additional Information eRAI No. 8938 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvalis, Oregon 97330, Office: 541.360.0500, Fax: 541.207.3928 www.nuscalepower.com
RAIO-1217-57850 :
NuScale Supplemental Response to NRC Request for Additional Information eRAI No. 8938 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvalis, Oregon 97330, Office: 541.360.0500, Fax: 541.207.3928 www.nuscalepower.com
Response to Request for Additional Information Docket No.52-048 eRAI No.: 8938 Date of RAI Issue: 08/07/2017 NRC Question No.: 03.12-2 According to SRP Section 3.12, Subsection II.D.x, the design of sliding type supports, such as
guides or box supports, should include evaluation of the friction loads induced by the pipe on
the support.
FSAR Tier 2, Section 3.12.6.9, Consideration of Friction Forces states that friction forces on
supports are considered only due to deadweight and thermal loads and no other loads are
considered to produce friction.
Friction force is developed and determined by the applied pipe force normal to the support
member surface multiplied by the appropriate coefficient of friction. Friction forces to be
considered are those that are produced by resulting piping signed loads. Signed loads are those
which act in one direction. These are considered for producing significant friction loads and
should be accounted for in the pipe support design. Cyclic loads, such as those from
earthquake or other reversing dynamic loads are not considered to produce significant friction
forces and friction forces from these loads can be ignored. For examples of reversing and
nonreversing dynamic loads see ASME Sect. III, Fig. NB-3213-1 and Fig. NC-3622-1.
Example of loads to be considered for producing frictional loads are those from deadweight,
thermal expansion loads, pipe anchor or support movement (due to temperature or pressure)
loads and from any nonreversing dynamic loads such as those from relief/safety valve open end
discharge loads.
- 1) Revise the FSAR to describe how the frictional forces on supports are determined from the above described loads, or provide a technical justification for omitting any of these loads/forces.
- 2) Document in the FSAR that friction loads from deadweight and thermal expansion loads are to be considered for all loading conditions or provide a technical justification for not including these friction forces from any loading condition.
NuScale Nonproprietary
NuScale Response:
Initial response to this RAI 8938 Question 03.12-2 Request 1 and 2 was provided by RAIO-1017-56422, dated October 5, 2017.
In a followup public telecon with NRC on November 28, 2017, it was requested that further clarification be provided in FSAR Tier 2, Section 3.12.6.10, relative to the types of loads that are considered to produce friction forces on supports, to better address RAI 8938 Question 03.12-2 Request #1.
This supplement 3.12-2S1 provides that clarification and revision to FSAR Tier 2, Section 3.12.6.10 and replaces the initial response to Request #1 in its entirety.
Request #1 Revise the FSAR to describe how the frictional forces on supports are determined from the above described loads, or provide a technical justification for omitting any of these loads/forces.
NuScale Response Consideration of frictional forces for the design of pipe supports is limited to loading from deadweight/buoyancy loads, thermal expansion loads, anchor or support movement (due to temperature or pressure), and other applicable signed loads, such as those from relief/safety valve discharge to an open system. Frictional forces are not considered for dynamic cyclic loads, such as those from an earthquake or reflected waves due to flow transients.
Clarification on how friction forces are determined has been added to FSAR Section 3.12.6.10, including the method of determining the direction of the frictional force and information on coefficients of friction other than for steel to steel. FSAR Tier 2, Section 3.12.6.10 has also been revised to clarify that, in addition to the loads listed therein, consideration of frictional forces for the design of pipe supports includes loading from applicable signed loads, including those from relief/safety valve discharge to an open system.
Impact on DCA:
FSAR Tier 2 Section 3.12.6.10 has been revised as described in the response above and as shown in the markup provided in this response.
NuScale Nonproprietary
ASME Code Class 1, 2, and 3 Piping Systems, Piping Components and NuScale Final Safety Analysis Report Associated Supports 3.12.6.10 Consideration of Friction Forces RAI 03.12-2 Frictional forces on pipe supports due to thermal expansion in the unrestrained direction(s) are determined using deadweight and thermal loads normal to the applicable support member. Friction forces due to other loads are not considered.
RAI 03.12-2S1 Friction load is determined using an appropriate coefficient of friction. A minimum coefficient of friction value of 0.30 is used for steel to steel (Reference 3.12-4).Frictional forces are considered for the design of pipe supports for applicable loading conditions.
Consideration of frictional forces is limited to loading from deadweight/buoyancy loads, thermal expansion loads, anchor or support movement (due to temperature or pressure), and other applicable signed loads, such as those from relief/safety valve discharge to an open system. Frictional forces are not considered for dynamic cyclic loads, such as those from an earthquake or reflected waves due to flow transients.
RAI 03.12-2, RAI 03.12-2S1 Frictional forces are not calculated in the piping analysis; rather they are manually determined when performing stress analysis of the pipe supports. The magnitude of the frictional force is the applied pipe force normal to the support surface multiplied by the appropriate coefficient of friction. Frictional forces act in the direction of pipe movement (i.e., the unrestrained direction). If pipe movement due to operating and service conditions reverse, the frictional force is considered in both the positive and negative directions.
RAI 03.12-2 A coefficient of friction value of 0.30 is used for steel to steel interfaces. A lower coefficient of friction may be justified if low friction slide/bearing plates are used, with the minimum value being 0.10.
3.12.6.11 Pipe Support Gaps and Clearances RAI 03.12-3, RAI 03.12-3S1 A nominal cold condition gap of one-sixteenth1/16th inch is included radially for allrigid guide pipe supports, except for deadweight supports. Deadweight supports are specified to be in contact with the piping in the direction of gravity, with a gap of one-eighth inch above the pipe when providing vertical restraint. These gaps allow unrestrained radial thermal expansion of piping and unrestrained rotation. A support gap of 1/16th inch around piping provides a total maximum unrestrained span of 1/8th inch in a given direction (in the plane of restraint). Pipe support gaps in the unrestrained direction(s) are specified large enough to accommodate the maximum deflection of the piping systems at the support.
RAI 03.12-3 Tier 2 3.12-30 Draft Revision 1
ASME Code Class 1, 2, and 3 Piping Systems, Piping Components and NuScale Final Safety Analysis Report Associated Supports are used, the working range given in manufacturer catalog load tables is used to determine travel range limits Where rods or strut supports are used in the design, a tolerance of 1 degree is applied to the manufacturer given swing angle limit. Correspondingly, the installation tolerances of these types of supports is 1 degree. Maximum displacements and rotations at flexible piping joints in ASME B31.1 piping are verified to be within the manufacturer's recommended limits.
The NuScale Power Plant does not use any specialized stiff pipe clamps that would induce high local stresses on the pipe, as discussed in NRC Information Notice 83-80.
3.12.7 References 3.12-1 American Society of Mechanical Engineers Boiler and Pressure Vessel Code, 2013 edition,Section III, Division 1, "Rules for Construction of Nuclear Facility Components," no addenda, New York, NY.
3.12-2 "Report of the U.S. Nuclear Regulatory Commission Piping Review Committee, Evaluation of Other Loads and Load Combinations," NUREG 1061 Volume 4, December 1984.
3.12-3 American Society of Mechanical Engineers, Power Piping - ASME Code for Pressure Piping B31, ASME B31.1, New York, NY.
RAI 03.12-2S1 3.12-4 Welding Research Council, Inc. "Position Paper on Nuclear Plant Pipe Supports,"
WRC Bulletin 353, May 1990, Shaker Heights, OH.Not used.
3.12-5 Institute of Electrical and Electronics Engineers, "Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations," IEEE Standard 344-1987, Piscataway, NJ.
3.12-6 Electric Power Research Institute, "Materials Reliability Program: Management of Thermal Fatigue in Normally Stagnant Non-Isolable Reactor Coolant System Branch Lines (MRP-146, Revision 1)," EPRI TR-1011955, June 22, 2011, Palo Alto, CA.Not used.
3.12-7 Electric Power Research Institute, "Thermal Stratification, Cycling, and Striping (TASCS)," EPRI TR-103581, July 7, 1999, Palo Alto, CA.
3.12-8 American National Standards Institute/American Institute of Steel Construction, "Specification for Safety-Related Steel Structures for Nuclear Facilities," ANSI/AISC N690-12, January 31, 2012, Chicago, IL.
3.12-9 American Institute of Steel Construction, "Steel Construction Manual," 14th ed.
Chicago, IL.
Tier 2 3.12-32 Draft Revision 1
Response to Request for Additional Information Docket No.52-048 eRAI No.: 8938 Date of RAI Issue: 08/07/2017 NRC Question No.: 03.12-3 According to SRP Section 3.12, Subsection II.D.xi, pipe support gaps should account for the
diametrical expansion of the pipe due to pressure and temperature.
FSAR Tier 2, Section 3.12.6.10, Pipe Support Gaps and Clearances states that a nominal cold
condition gap of 1/16 inch is included radially for all pipe supports. This gaps allow for
unrestraint radial thermal expansion of the pipe as well as unrestrained pipe rotation.
- 1. Discuss in the FSAR how the specified pipe support gap will be checked against the maximum combined radial growth of the pipe due to temperature and pressure to assure that adequate clearance exists to avoid binding, particularly for the 12 NPS main steam line.
- 2. The statement in the FSAR that a nominal cold condition radial gap of 1/16 inch is included in all pipe supports does not accommodate pipe supports that are designed to support deadweight. Modify the pipe support gap statement in the FSAR for deadweight supports.
NuScale Response:
Response to this RAI 8938 Question 03.12-3 Parts 1 and 2 was originally provided by RAIO-1017-56422, dated October 5, 2017.
In a followup public telecon with NRC on November 28, 2017, it was requested that further clarification be provided in FSAR Tier 2, Section 3.12.6.11, relative to the nominal cold condition radial support gaps for deadweight supports, to better address the RAI 8938 Question 03.12-3 Part 2.
NuScale agreed to supplement its original response to this RAI Question 03.12-3 Part 2 with the following clarification and revision to FSAR Tier 2, Section 3.12.6.11 for deadweight supports.
FSAR Tier 2, Section 3.12.6.11 has been revised to clarify that deadweight supports are specified to be in contact with the piping in the direction of gravity when the piping is in the cold condition.
NuScale Nonproprietary
Impact on DCA:
FSAR Tier 2 Section 3.12.6.11 has been revised as described in the response above and as shown in the markup provided in this response.
NuScale Nonproprietary
ASME Code Class 1, 2, and 3 Piping Systems, Piping Components and NuScale Final Safety Analysis Report Associated Supports 3.12.6.10 Consideration of Friction Forces RAI 03.12-2 Frictional forces on pipe supports due to thermal expansion in the unrestrained direction(s) are determined using deadweight and thermal loads normal to the applicable support member. Friction forces due to other loads are not considered.
RAI 03.12-2S1 Friction load is determined using an appropriate coefficient of friction. A minimum coefficient of friction value of 0.30 is used for steel to steel (Reference 3.12-4).Frictional forces are considered for the design of pipe supports for applicable loading conditions.
Consideration of frictional forces is limited to loading from deadweight/buoyancy loads, thermal expansion loads, anchor or support movement (due to temperature or pressure), and other applicable signed loads, such as those from relief/safety valve discharge to an open system. Frictional forces are not considered for dynamic cyclic loads, such as those from an earthquake or reflected waves due to flow transients.
RAI 03.12-2, RAI 03.12-2S1 Frictional forces are not calculated in the piping analysis; rather they are manually determined when performing stress analysis of the pipe supports. The magnitude of the frictional force is the applied pipe force normal to the support surface multiplied by the appropriate coefficient of friction. Frictional forces act in the direction of pipe movement (i.e., the unrestrained direction). If pipe movement due to operating and service conditions reverse, the frictional force is considered in both the positive and negative directions.
RAI 03.12-2 A coefficient of friction value of 0.30 is used for steel to steel interfaces. A lower coefficient of friction may be justified if low friction slide/bearing plates are used, with the minimum value being 0.10.
3.12.6.11 Pipe Support Gaps and Clearances RAI 03.12-3, RAI 03.12-3S1 A nominal cold condition gap of one-sixteenth1/16th inch is included radially for allrigid guide pipe supports, except for deadweight supports. Deadweight supports are specified to be in contact with the piping in the direction of gravity, with a gap of one-eighth inch above the pipe when providing vertical restraint. These gaps allow unrestrained radial thermal expansion of piping and unrestrained rotation. A support gap of 1/16th inch around piping provides a total maximum unrestrained span of 1/8th inch in a given direction (in the plane of restraint). Pipe support gaps in the unrestrained direction(s) are specified large enough to accommodate the maximum deflection of the piping systems at the support.
RAI 03.12-3 Tier 2 3.12-30 Draft Revision 1