1、Transducer and TransmitterInstallation for Nuclear SafetyApplicationsReaffirmed 16 September 2002ANSI/ISA67.01.012002Formerly ANSI/ISA67.011994AMERICAN NATIONAL STANDARDISA The Instrumentation,Systems, andAutomation Society TMANSI/ISA-67.01.01-2002Transducer and Transmitter Installation for Nuclear
2、Safety ApplicationsISBN: 1-55617-837-9Copyright 2002 by ISA The Instrumentation, Systems, and Automation Society. All rights reserved.Not for resale. Printed in the United States of America. No part of this publication may be reproduced,stored in a retrieval system, or transmitted in any form or by
3、any means (electronic mechanical,photocopying, recording, or otherwise), without the prior written permission of the Publisher.ISA67 Alexander DriveP.O. Box 12277Research Triangle Park, North Carolina 27709- 3 - ANSI/ISA-67.01.01-2002PrefaceThis preface, as well as all footnotes and annexes, is incl
4、uded for information purposes and is not part ofANSI/ISA-67.01.01-2002.This document has been prepared as part of the service of ISAthe Instrumentation, Systems, andAutomation Societytoward a goal of uniformity in the field of instrumentation. To be of real value, thisdocument should not be static b
5、ut should be subject to periodic review. Toward this end, the Societywelcomes all comments and criticisms and asks that they be addressed to the Secretary, Standards andPractices Board; ISA; 67 Alexander Drive; P. O. Box 12277; Research Triangle Park, NC 27709;Telephone (919) 549-8411; Fax (919) 549
6、-8288; E-mail: standardsisa.org.The ISA Standards and Practices Department is aware of the growing need for attention to the metricsystem of units in general, and the International System of Units (SI) in particular, in the preparation ofinstrumentation standards. The Department is further aware of
7、the benefits to USA users of ISAstandards of incorporating suitable references to the SI (and the metric system) in their business andprofessional dealings with other countries. Toward this end, this Department will endeavor to introduceSI-acceptable metric units in all new and revised standards, re
8、commended practices, and technicalreports to the greatest extent possible. Standard for Use of the International System of Units (SI): TheModern Metric System, published by the American Society for Testing b) containment isolation;c) reactor core cooling;d) containment or reactor heat removal;e) pre
9、vention or mitigation of a significant release of radioactive material to the environment; orf) maintaining safe shutdown conditions;or is otherwise essential to provide reasonable assurance that a nuclear power plant can be operatedwithout undue risk to the health and safety of the public.3.6 off-l
10、ine:transducers that are either connected to the process fluid via sensing lines with one or more isolationvalves or are not exposed to the process fluid.*See references and bibliography.ANSI/ISA-67.01.01-2002 - 12 -3.7 pressure boundary integrity:the capability to retain process fluid.3.8 qualified
11、:demonstrated to be acceptable for the design requirements.3.9 sensing line:piping or tubing connecting a transducer to the process.3.10 allowable stress:the stress values allowed by the applicable piping or structural design standard.4 Safety classification4.1 Code applicabilityThe reason that a tr
12、ansducer is classified as safety-related is important in determining which of the criteriain this document shall be applicable. In general, transducers are classified as safety-related for one ormore of the following reasons:a) Pressure boundary integrityb) MountingThe transducer must be mounted in
13、a manner that prevents it from affecting the performance of othersafety-related equipment, such as following a seismic event.c) Electrical connectionThe transducer must be electrically installed in a manner that prevents it from affecting theperformance of other safety-related equipment.d) FunctionT
14、he transducers signal is to be utilized in the performance of a safety-related function.If the reason that a transducer is classified as safety-related is its function, then all of the criteria of thisdocument should be considered for applicability. However, if a transducer is safety-related due to
15、one ofthe other three reasons, only certain criteria within this document need to be considered for applicability.Consider, for example, a transducer whose only safety-related function is its pressure boundary. Thosecriteria within this document relative to ensuring that the transducer maintains the
16、 pressure boundarywould be applicable to the transducer. Criteria associated with electrical connections, separation,calibration, testing, etc. may not be relevant to such a transducer. Similarly, the user of a transducerwhose only safety-related function is its electrical connection would find the
17、criteria of this standardassociated with maintaining that electrical connection to be applicable. Criteria associated with process-fluid connections, environmental considerations, accessibility, etc. may not be applicable for such atransducer.It is the responsibility of the user to determine the rea
18、sons that a transducer is classified as safety-relatedand to apply the criteria of this document that will maintain these safety-related functions.4.1.1 In-line transducersInstallations of transducers in Code piping, vessels, or equipment shall comply with the Code.- 13 - ANSI/ISA-67.01.01-2002Trans
19、ducers for nuclear safety-related applications may be installed in or connected to non-Code piping,vessels, or equipment, as necessary to obtain measurements from non-Code systems. The Code shallnot apply to these installations.4.1.2 Off-line transducersThe Code shall not apply to off-line transduce
20、rs. Sensing lines for off-line transducers shall be installed inaccordance with ANSI/ISA-67.02.01-1999.*4.1.3 Mounting structuresMounting structures that support Code equipment shall comply with the Code (subsection NF).5 Equipment mounting5.1 Mounting of in-line transducers5.1.1 Flow-through device
21、sTo facilitate replacement and periodic inspections, flow-through transducers, such as differential pressuremeters (orifice plates, flow nozzles, venturi tubes, etc.), electromagnetic flowmeters, mass flowmeters,vortex flowmeters, positive displacement flowmeters, turbine flowmeters, ultrasonic flow
22、meters, variablearea flowmeters, and certain radiation monitors should be flange-mounted to the piping, except in ASMECode Class 1 installations.The piping shall not impose unacceptable loads on the instrument. Auxiliary supports shall be provided torestrain the instrument where the mass of the inst
23、rument puts unacceptable stress on the piping.5.1.2 Flow-past devicesFlow-past devices (such as protective wells, differential pressure meters pitot tubes, insertion-typeelectromagnetic vortex, target, and turbine flowmeters) designed to be inserted into the flow path throughthe wall of the pipe or
24、vessel, shall be installed and mounted through a piping penetration specificallydesigned to accommodate the transducer.Where removal is required for service, one of the following alternatives to permanent welding of thetransducer shall be used:a) A qualified flange connectionb) For insertion shank d
25、iameters of 25 mm OD (1 in.) or less, mounting with a flareless fitting (see 8.2.3)Mating fittings shall be welded into the pipe boss or fitting. The mating bodies, nuts, and ferrules shallbe obtained from the same manufacturer or shall otherwise be qualified to perform their intendedfunction.c) Des
26、igns permitting removal of transducers from pressurized systemsThey shall provide positive nonfriction restraint in both the inserted and the withdrawn position.d) Straight threads with resilient seals, and conical or spherical seat unionsANSI/ISA-67.01.01-2002 - 14 -5.2 Mounting of off-line transdu
27、cers5.2.1 Mounting structure designThe mounting structure shall not induce stresses greater than the allowable stresses on the transducer oron the sensing lines, signal lines, and electrical cables serving the transducer.The structure shall be designed to support the transducer in the physical orien
28、tation(s) for which it isqualified. Only qualified mounting hardware shall be used. Preference should be given to use of hardwarefurnished and qualified as part of the transducer.Mounting structures and their attachments shall have a load capacity not less than that required by any ofthe supported t
29、ransducers or auxiliary equipment.5.2.2 FastenersBolts, screws, or other fasteners used for mounting shall be chemically and metallurgically compatiblewith the equipment, the structure, and the environment. Fasteners shall be qualified to withstand all loadsincluding normal loads, structural vibrati
30、ons, and seismic stresses.5.2.3 MaterialsThe materials selected for the mounting structures shall be resistant to or protected against the designenvironment; for example, aluminum may be prohibited in caustic spray environments.Protective coatings shall be resistant to both normal and (where applica
31、ble) accident environments, andthe coatings shall be chemically and metallurgically compatible with the materials to be protected. Paintsor paint-type coatings used on mounting structures shall be fire-retardant.5.2.4 Mounting structure configurationsOne of the following configurations shall be used
32、 for mounting:a) Wall bracketb) Open rack (partial combination with cabinet-type structure)The addition of flat plate side panels or cross-bracing is permitted to obtain satisfactory stiffness.Bracing to the wall or other structures is permitted.c) Cabinet (totally enclosed construction)Unless cabin
33、ets are designed specifically to control the transducer environment, they shall bedesigned to allow natural air circulation. Where a controlled environment is essential to the accuracyor continued function of the enclosed equipment, the auxiliary equipment for controlling theenvironment shall be des
34、igned and installed to the same requirements as the enclosed equipment.Monitoring of the controlled environment parameters shall be provided.d) Panels (flat plates attached to open racks, wall brackets, or cabinets, as defined in 5.2.4.(c)e) Pipe stands or stanchions (a single length or assembly of
35、pipe or structural shapes that is mounted tothe floor, wall, or structural steel)Friction mounting of the bracket (such as that provided by U-bolt clamps around a pipe) may be usedwhen qualified.- 15 - ANSI/ISA-67.01.01-20025.2.5 Construction and assembly methodsBolting methods shall meet the requir
36、ements of 5.2.2.Attachments to Code components shall conform to the requirements of the Code.If welding is specified for non-Code attachment or assembly, the weld shall be shown to have a stressedcross section sufficient to support the maximum design loads. Tack welding shall not be used as astructu
37、ral weld.All welds shall be made in accordance with qualified procedures.Other assembly methods (such as bonding or adhesives) shall be qualified for all structural,environmental, and design-life conditions.5.2.6 Mounting structure attachmentThe mounting structure shall be attached to its supporting
38、 structure by bolting or welding in place.Plates connected to embedded anchors, expansion bolts, cement, or other means of attachment inconcrete are acceptable.5.2.7 Inspection requirements for mountingsInspection of the final assembly shall be performed and documented to verify thata) fasteners use
39、d are the size, type, and material specified and have been properly tightened;b) welding is as specified;c) paint and other protective coatings have been applied as specified to corrodible;d) materials, and that the coating remains intact or has been repaired;e) transducers and auxiliary equipment i
40、tems are installed in the orientation appropriate for seismicqualification, and the designated mounting brackets or supports shown on the approved designdrawings have been properly installed;f) piping, tubing, fittings, valves, and electrical connections have been installed and tested inaccordance w
41、ith the drawings or specifications; andg) nondestructive examination, if specified on the drawings or other documents, has been completed.5.3 Mechanical protectionImpingement barriers shall be used where required to protect against damage from postulated missiles,fluid jets, and other identified mov
42、ing objects. The barriers may also serve to separate redundanttransducers and auxiliary equipment. The barriers shall be designed consistent with the seismicqualification requirements for the protected devices.5.4 Auxiliary equipmentUnless otherwise justified, the requirements of 5.2 and 5.3 shall a
43、pply to auxiliary equipment.ANSI/ISA-67.01.01-2002 - 16 -6 Location of equipment6.1 Selecting a location6.1.1 Transducers shall not be installed in locations with environments that may exceed the qualifiedcapabilities of the transducer, except when it can be shown that a potentially adverse environm
44、ent willexist only after the transducers function is no longer required. For instance, transducers with no post-accident requirements may be located in the reactor containment without being qualified for post-accidentenvironments, so long as their failure will not degrade the availability of other e
45、quipment that is requiredto be operable. Selection of locations for transducers should consider the availability of transducersqualified to operate in the various design environments.6.1.2 Transducers shall be located or enclosed as necessary to protect them against physical damage,radiation, freezi
46、ng, and changes or rates-of-change in ambient conditions in excess of that for which theyhave been qualified.6.2 Separation of redundant transducers6.2.1 Transducers shall be located so that no credible single event can prevent the required nuclearsafety-related functions. Piping, tubing, and wiring
47、 associated with the transducers shall be placed withsimilar attention to separation of locations. A minimum of 450 mm (18 in.) separation shall be providedbetween surfaces of redundant transducers. Where analysis shows that specific postulated events,including but not limited to fires, missiles, an
48、d fluid jets, could circumvent the protection afforded by thisseparation, additional spacing or protective barriers shall be provided. Protective barriers may also beused in lieu of separation where it is impractical to maintain the required spacing. If barriers are used, aminimum of 25 mm (1 in.) o
49、f free space shall be provided on each side between transducers and thebarrier.6.2.2 Where redundant transducers must be included on the same structure, service access to thetransducers, or to the subassemblies of one transducer, shall be separated from access to componentsor subassemblies of their redundant counterpart(s). (For instance, with cabinet construction, separateaccess doors should be provided.)6.3 Accessibility for periodic test and service6.3.1 The transducers should be located in an accessible place for ease of periodic testing, servicing,removal, and replacement.
