1、Standard for Light WaterReactor Coolant PressureBoundary Leak DetectionApproved 30 October 1982ISA67.031982Formerly ISAS67.031982STANDARDISA The Instrumentation,Systems, andAutomation Society TMCopyright GA4 1982 by the Instrument Society of America. All rights reserved. Printed in the UnitedStates
2、of America. No part of this publication may be reproduced, stored in a retrieval system, ortransmitted in any form or by any means (electronic, mechanical, photocopying, recording, orotherwise), without the prior written permission of the publisher.ISA67 Alexander DriveP.O. Box 12277Research Triangl
3、e Park, North Carolina 27709ISA-67.03-1982, Standard for Light Water Reactor Coolant Pressure Boundary Leak DetectionISBN 0-87664-734-4ISA-S67.03-1982 3PrefaceThis preface is included for information purposes and is not part of ISA-67.03-1982.This Standard has been prepared as a part of the service
4、of ISA toward a goal of uniformity in the field of instrumentation. To be of real value, this document should not be static, but should be subject to periodic review. Toward this end, the Society welcomes all comments and criticisms, and asks that they be addressed to the Secretary, Standards and Pr
5、actices Board, ISA, 67 Alexander Drive, P.O. Box 12277, Research Triangle Park, NC 27709, Telephone (919) 549-8411, e-mail: standardsisa.org.The ISA Standards and Practices Department is aware of the growing need for attention to the metric system of units in general, and the International System of
6、 Units (SI) in particular, in the preparation of instrumentation standards. The Department is further aware of the benefits to USA users of ISA standards of incorporating suitable references to the SI (and the metric system) in their business and professional dealings with other countries. Towards t
7、his end this Department will endeavor to introduce SI-acceptable metric units in all new and revised standards to the greatest extent possible. The Metric Practice Guide, which has been published by the American Society for Testing and Materials as ANSI designation Z210.1 (ASTM E380-76, IEEE Std. 26
8、8-1975), and future revisions, will be the reference guide for definitions, symbols, abbreviation, and conversion factors.It is the policy of ISA to encourage and welcome the participation of all concerned individuals and interests in the development of ISA standards. Participation in the ISA standa
9、rds making process by an individual in no way constitutes endorsement by the employer of that individual of ISA or any of the standards which ISA develops.The American National Standards Institute (ANSI) assigned work on this standard to ISA Committee SP-67 “Nuclear Power Plant Standards“ in Decembe
10、r, 1973. The assignments, considered a priority project needing urgent and prompt action, was given to Subcommittee SP-67.03 chaired by M. J. Kimbell during the May 20, 1974 Boston ISA Power Conference. The subcommittee performed a literature search of leak test standards and current nuclear power p
11、lant practice in relation to reactor coolant leak detection for representative pressurized water and boiling water power reactors. This information was utilized during the preparation of this Standard together with comments received from concerned reviewers.The information contained in this preface,
12、 the footnotes and attached Appendices A and B is included for information only and is not a part of the Standard.The following individuals served as members of the ISA Subcommittee SP-67.03 which prepared this standard:NAME COMPANYU. Shah, Chairman Washington Public Power Supply SystemM. J. Kimbell
13、 Bechtel, Inc.B. G. Atraz General Electric Co.J. Dodds Bechtel Power CorporationJ. Hersey Bechtel Power CorporationM. Hildenbrand Nuclear Measurements Corp.4 ISA-S67.03-1982R. Ulman Victoreen Inst. Co.L. S. Loomer Bechtel Power CorporationR. M. Norris Washington Public Power Supply SystemM. F. Reisi
14、nger Combustion Engineering, Inc.B. Segal U.S. Nuclear Regulatory CommissionG. B. Stramback General Electric CompanyI. Sturman Bechtel Power CorporationT. N. Crawford Pacific Gas and Electric Co.J. H. Gebert Iowa Electric Light “Process Instrumentation Terminology.“Boiling Water Reactor (BWR): A nuc
15、lear steam supply system in which process steam is generated in the reactor vessel.Calibration: “The adjustment of device or series of devices, in order to bring the output to a desired value, within a specified tolerance, for a particular value of input.“ Reference: ISA S51.1-1979.Coolant: The flui
16、d contained within the reactor coolant pressure boundary.Leak: An opening, however minute, that allows undesirable passage of a fluid from its containing boundaries.Leakage: The fluid that passes through a leak. The fluid referred to in this Standard is the primary coolant water unless otherwise sta
17、ted.Abnormal leakage: That leakage from the Reactor Coolant Pressure Boundary(RCPB) which is considered to be unusual, unexpected or in excess of technicalspecification allowances.Allowable leakage: That leakage value defined in plant operational technicalspecifications above which plant operation m
18、ust be altered or interrupted as nec-essary to perform corrective actions to reduce the leakage to allowable values.Identified Leakage: See Section 5.1.1.Leakage Rate: Leakage expressed in volumetric units per unit of time at 20C andone atmosphere pressure.Unidentified Leakage: See Section 5.1.1 and
19、 5.1.2.Monitoring instrument system: A system that provides information about RCPB leakage conditions so that the operator can take action.Nuclear Safety Related (NSR): Instrumentation “which is essential to: 1) Emergency Reactor Shutdown; 2) Containment Isolation; 3) Reactor Core Cooling; 4) Contai
20、nment or Reactor Heat Removal; 5) prevention or mitigation of a significant release of radioactive material to the environment or, is otherwise essential to provide reasonable assurance that a nuclear power plant can be operated without undue risk to the health and safety of the public.“ Reference:
21、ISA S67.01-1979.Non-Nuclear Safety (NNS): Instrumentation not included in NSR.Operating Basis Earthquake (OBE): That earthquake which “. . . could reasonably be expected to affect the plant site during the operating life of the plant; it is that earthquake which produces the vibratory ground motion
22、for which those features of the nuclear power plant necessary for continued operation without undue risk to the health and safety of the public are designed to remain functional.“ Reference 10CFR100, Appendix A, III(d).ISA-S67.03-1982 11Pressurized Water Reactor (PWR): A nuclear steam supply system
23、in which the pressurized primary coolant fluid is heated by the reactor core, and the process steam is generated in a steam generator by heat transfer from the primary coolant.Primary containment: The structure that encloses the reactor coolant pressure boundary.Reactor Coolant Pressure Boundary (RC
24、PB): “all those pressure-containing components of boiling and pressurized water-cooled nuclear power reactors, such as pressure vessels, piping, pumps, and valves, which are:1) Part of the reactor coolant system, or2) Connected to the reactor coolant system, up to and including any and all of the fo
25、llowing:i) The outermost containment isolation valve in system piping which penetrates primary reactor containment.ii) The second of two valves normally closed during normal reactor operation in system piping which does not penetrate primary reactor containment.iii) The reactor coolant system safety
26、 and relief valves.For nuclear power reactors of the direct cycle boiling water type, the reactor coolant system extends to and includes the outermost containment isolation valve in the main steam and feedwater piping.“ Reference: 10CFR50, Section 50.2(v).Sensitivity: “. . . ratio of the change in o
27、utput magnitude to the change of the input which causes it after the steady-state has been reached.“ Reference: ISA S51.1-1979.Time constant: “The time required for the output of a first-order system forced by a step change to complete 63.2 percent of the total rise or decay.“ Reference: ISA S51.1-1
28、979.Time response of instrumentation: “. . . an output expressed as a function of time, resulting from the application of a specified input under specified operating conditions.“ Reference: ISA S51.1-1979.5 Leakage classifications and sourcesThe significance of leakage from the RCPB will depend upon
29、 the leak location, the leakage rate, duration, and the nature of the flow path permitting the leakage. Through-wall cracks or flaws are the most difficult to detect and monitor because they can occur at any RCPB location. This type of leak is also of most concern because the leak may develop from s
30、ome unpredicted combination of internal defects and external stresses in a nonisolatable portion of the RCPB.5.1 Leakage classificationsA principal concern in leakage monitoring is the capability to discriminate between unidentified leakage from the RCPB and leakage from identifiable sources into th
31、e containment. Being able to discriminate allows more rapid and reliable assessment of plant operating conditions. The following leakage classifications, as used in this standard, facilitate identification of leakage sources and interpretation of leakage data:12 ISA-S67.03-19825.1.1 Identified leaka
32、gea) Leakage into collection systems, e.g., pump seal or valve packing leakage that is collected and measured, orb) Leakage into the containment which meets all of the following conditions:1) The leaks have been specifically located and the rate quantified.2) The leaks are not cracks or flaws in the
33、 RCPB.An example of b) above is a quantified leakage of component cooling water into thecontainment.5.1.2 Unidentified leakageLeakage into the containment which is not classified as identified leakage.5.1.3 Intersystem leakageCoolant leakage across RCPB passive barriers such as heat exchanger tubes
34、or tube sheets into other closed systems. Such leakage is not normally released to the containment atmosphere and is a separate classification.5.1.4 Other leakageAny leakage not from the RCPB and outside of the reactor containment structure, if not covered by the above classifications. An example of
35、 such leakage could be leakage from steam or feedwater lines outside the containment structure of a BWR plant. A summary of such leakage sources and typical detection methods frequently used is given in Appendix A of this standard.5.2 Potential identified leakage sourcesVariations in plant designs d
36、o not allow a single definitive check list of all potential leakage sources. However, probable leakage sources can be identified during plant design and appropriate leakage detection, measurement and collection (leakoff) systems provided. Collection and isolation, to the extent practical, of leakage
37、 from identified sources enhance the monitoring capability for unidentified leakage. The following are some of the more common types of leakage sources that can be easily identified:a) Dynamic seals such as valve stem packing, pump drive shaft seals and control rod drive gland seals.b) Static seals
38、such as the reactor head pressure seals, equipment gaskets and valve seat seals in lines connected to the RCPB.c) Pressure relief systems such as pressure relief valves, rupture disks and safety relief valves.d) Passive interface boundaries with the RCPB such as instrument bellows, diaphragms and Bo
39、urdon tubes, thermometer wells and heat exchanger tubes.ISA-S67.03-1982 136 General design requirementsThis standard is not intended to replace applicable handbooks and texts, such as References (11) and (12), which provide detailed design and analytical techniques. Suggested methods and procedures
40、for developing required design information are given in the references and appendices to this standard.6.1 Principal monitoring systems for unidentified leakageAt least three dissimilar, diverse, and independent principal methods of monitoring coolant leakage from the RCPB to the containment shall b
41、e provided. One of these methods shall be sump level and/or sump flow monitoring. Other acceptable methods are identified in Section 7 and Ta ble 1.6.2 Coolant leakage detection system performanceThe sensitivity and response characteristics for each of three principal leak detection monitoring syste
42、ms shall be shown by design calculations or performance tests to be capable of indicating and alarming a 1 gpm (3.8 liters/min) leakage increase within one hour. It is recognized that some systems other than sump monitoring may not be capable of meeting this requirement during certain normal plant o
43、perating conditions. In these cases, these systems shall be designed for leakage sensitivity that is as high as reasonably achievable. When identified leakages are superimposed on unidentified leakages the above sensitivity requirements shall apply also.6.3 Safety classificationThe RCPB leak detecti
44、on systems covered in this standard are non-nuclear safety systems or monitoring instrument systems.6.4 Collecting and measuring identified leakagesSeals, relief systems, and other probable sources of leakage shall be identified. Leakage collection and measurement systems shall be provided for suffi
45、cient identified sources to limit the expected leakage to the containment atmosphere to the extent practical. The residual uncollected liquid leakage shall not prevent unidentified liquid leakage monitoring systems from meeting Section 6.2 requirements.Leakage to the primary reactor containment from
46、 identified sources shall be collected or otherwise isolated so that:a) The flow rates from identified leaks are monitored separately from unidentified leaks.b) The total flow rate from identified leaks can be established and monitored with a sensitivity capable of detecting a 1 gpm (3.8 liters/min)
47、 leakage increase within 1 hr for PWR plants and 2 gpm (7.6 liters/min) leakage increase within 1 hr for BWR plants.6.5 Monitoring intersystem leakageProvisions shall be made to monitor systems connected to the RCPB through passive barriers for indications of intersystem leakage. Acceptable methods
48、include radioactivity monitoring and water inventory monitoring. See Appendix A for additional information.14 ISA-S67.03-19826.6 System availabilityThe RCPB leakage detection systems shall be designed to operate whenever the plant is not in cold shutdown condition.6.6.1 Ambient conditionsMonitoring
49、system shall be designed to maintain specified accuracy and performance features for the range of ambient temperature, humidity, and radiation levels that are expected at the component locations during normal plant operations.6.6.2 Seismic eventsThe sump monitoring system and at least one of the other diverse monitoring channels provided shall be demonstrated to be acceptable for the design requirements after any seismic event for which plant shutdown is not required, i.e., less than an operating basis earthquake. The guidelines of IEEE Standard 344, Reference (6), may be used for seis
