Regulatory Guide 1.51
| ML13350A361 | |
| Person / Time | |
|---|---|
| Issue date: | 05/31/1973 |
| From: | US Atomic Energy Commission (AEC) |
| To: | |
| References | |
| RG-1.051 | |
| Download: ML13350A361 (2) | |
4"'*1*.(L.4`U.S. ATOMIC ENERGY COMMISSION
R GULATORY DIRECTORATE
OF REGULATORY
STANDARDS May 1973 GUIDE INSEF REGULATORY
GUIDE 1.51 IVICE INSPECTION
OF ASME CODE CLASS 2 AND 3 NUCLEAR POW
A. INTRODUCTION
General Design Criteria 36. "Inspection of Emergency Core Cooling System." 39. "Inspection of Containment Heat Removal System." 42, "Inspection of Containment Atmosphere Cleanup Systems," and 45."Inspection of Cooling Water System," of Appendix A to 10 CFR Part 50. "Generzl Desian Criteria for Nuclear Power Plants," require that the subject systems be designed to permit appropriate periodic inspection of important component parts of the systems to assure system integrity and capability.
Regulatory Guide 1.26 (Safety Giuide 26). "Quality Group Classification and Standards," in conjunction with § 50.55a of 10 CFR Part 50 describes a quality classification system related to specified industry codes that may be used to determine quality standards for water- and steam-containing components important to the safety of water-cooled nuclear power plants. This guide describes acceptable methods of implementing the periodic inservice inspection requirements for American Society of Mechanical Engineers (ASME) Code Class 2 and 3 components.
This guide applies to light-water-cooled reactors.
The Advisory Committee on Reactor Safeguards has been consulted concerning this guide and has concurred in the regulatory position.
B. DISCUSSION
The ASME Boiler and Pressure Vessel Code (ASME B&PV Code),Section XI, "Rules for Inservice Inspection of Nuclear Reactor Systems."'
specifies requirements for ilservice inspection of Code Class 12'Copies may he obtained from American Society of Mechanical Enqincers.
United Engineering Center, 345 Ea'st 47th Street, New York, N.Y. 100 17.IC6mponents classified as AEC Quality Group A. B, and C should conform to the requirements of the ASSlI' Boiler and Pressure Vessel Code for Class I. 2. and 3 components, resp ctivel
y. TER PLANT COMPONENTS
componen ts. In the Winter 1972 Addenda to Section XI, 3 acceptable inservice inspection requirements are specified for Code Class 22 components.
Code Class 32 components are not presently included in Section X1 requirements, but they should also be part of the scheduled inservice inspection program. The inspection requirements need not be as extensive as those required for Code Class 2 components but should, as a minimum.include visual inspection of Code Class 3 componentb and their supports.
For such inspections to be effective.
they should be performed at periods when the components are under pressure of sutficienti nagnitude to properly represent the intended service condition.
This may require that the inspections of Code Class 'components be scheduled to coincide with system performance tests, component functional tests, and system pressure tests in order to benefit from the pressure levels established for these tests.Section XI defines an inspection interval for Code Class I and 2 components as 10 years, and the inservice inspection program for Code Class 3 components should be based on the same time interval.Code Class 3 components required to function during normal reactor operation would generally he accessible during reactor downtime, and they should be inspected at least once toward the end ot each inspection interval.
Components in systems or portiovri of systems which are not required to futiction during reactor operation can be inspected independently of reactor downtime.The visual inspection of Code Class 3 components should be conducted for signs or evidence of leak.:'c caused by structural distress or corrosion effects on the, components.
In addition, supports and hangers lilt piping and Code Class 3 componenls over 4 inches ill dianicter should be inspected for evidence of inadcqmtm support, unintended restrmint.
or structur:al distress."ASME B&PV Code, Sectiotni Xl. Wintter 1972 Addtend
a. USAEC REGULATORY
GUIDES Copies of publiihed guide% may be obtained by es.luftl indicating the div~iun;desired to the US. Atomic Energy Cumr,$,s.on.
Washtrinton.
DZ.. 2CS4t.Regulatory Guides are issued /o describe and ,'r1te available lt. the public Attention:
Director of negulatnry Stsnd3ordi.
Coermtnts , I-itethods acceptbhle to the AEC Rl'gulatory stifl of imnplemrnting specific pants of imirovemlrts in htfe gklir Mi enc)ur'ed and should be %tnt to ite SetjPri the Comminsion's tegulisions, to dielinete uStit by 9.- staff in of the U.S. Alomic Enetriv Cunmmostun.
Vlh.hirigit..
D.C. 20U-45.e'llualtng specific problems or pOstulated at to provide gait'enco in Attention:
Chief. Pubic Proceedings Sliit.applicants.
Regulatory Guides ere not substitutes for 'eguitiuni And compliance with them it not requirad.
Methodt and differont frmt ihoos %st out in The guides are issued in the follosring ton brail drisic.ni:
the guides wvill be acceputable if they provide a batis far tim finrdmtlt reQuitl-l to the i muan tce ot continuance of a it of Icente by the Com m ,ssion. 2. R eIe ref end T itw* Re tcto t 7. T srini rtniin 3. Fuels anor M4teiitis FaitIlt," .
Heaslth Publihhed guiders will be revised periodicull,.
at apOraOrtipr., to accomnodate
4. Environtat.rll am Sam)t', 9. Antitrust Review eproetients and to reflect new infoorntatOn of experience.
S. Materitls
&nd Plant Protection
1
0. General
'I, The pressure developed in components during a system performance lest, a component performance test, or a system pressure test should be representative of conditions under which the systems should be leaktight during operation.
The lest pressure should be at least 110 percent of the system design pressure.
However. the pressure developed during the conduct of a periodic system performance test would be acceptable during inspections conducted in periods between the pressure tests. Certain components.
such as open storage tanks including piping to the first shutoff valve, cannot readily be pressure tested. The hydrostatic pressure developed with tanks filled to their design capacity would be an acceptable test pressure for such tanks and connected piping.C. REGULATORY
POSITION I. Inservice inspection requirements for ASME Code Class 22 components should comply with the ASME B&PV Code. Section X1 and the Winter 1972 Addenda'for Class 2 components except that subparagraph ISC-261(a)
should be changed to read as follows: "Components in systems or portions of systems which recirculate reactor coolant during normal reactor operation, and are designed for pressure and tempcrature in excess of either 275 psig or 200°F shall be examined in accordance with the requirements specified in Table ISC-261 ." 2. Inspection programs for ASME Code Class 32 components should be performed according to the following schedules:
a. All of the components should be pressure It tested and inspected at least once during each 10-year inspection interval.b. In addition, all components should be inspected during periods of normal reactor operation or during system performance testing at least once during every one-third of each inspection interval.3. Inspection requirements for ASME Code Class 3 components should include the following:
a. System pressure tests should be performed to the extent necessary to perform the component examination.
Test pressure should be at least: (1) For closed systems, 110 percent of the design pressure.(2) For open storage tanks, the nominal hydrostatic pressure developed with the tanks filled to design capacity.(3) Open-ended portions of systems may be exempted from pressure testing.b. Visual inspections for evidence of unanticipated component leakage, structural distress.
or corrosion.
c. Inspection of supports and hangers for piping and components over 4 inches in diameter for evidence of inadequate support, unintended restraint, or strurtural distress.4. Records of the inserice inspection should be established and maintained for the life of the plant and should include: a. Identification of systems components inspected;
b. Date of inspection;
c. Repair or replacement;
and d. Signature of employee certifying dte inspection was made.1.5 1-2