1、Designation:C99206 Designation: C992 11Standard Specification forBoron-Based Neutron Absorbing Material Systems for Usein Nuclear Spent Fuel Storage Racks1This standard is issued under the fixed designation C992; the number immediately following the designation indicates the year oforiginal adoption
2、 or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification defines criteria for boron-based neutron absorbing materi
3、al systems used in racks in a pool environmentfor storage of nuclear light water reactor (LWR) spent-fuel assemblies or disassembled components to maintain sub-criticality inthe storage rack system.1.2 Boron-based neutron absorbing material systems normally consist of metallic boron or a chemical co
4、mpound containingboron (for example, boron carbide, B4C) supported by a matrix of aluminum, steel, or other materials.1.3 In a boron-based absorber, neutron absorption occurs primarily by the boron-10 isotope that is present in natural boron tothe extent of 18.3 6 0.2 % by weight (depending upon the
5、 geological origin of the boron). Boron, enriched in boron-10 could alsobe used.1.4 The materials systems described herein shall be functional that is always be capable to maintain a B10 areal density suchthat subcriticality Keff 0.95 or Keff 0.98 or Keff 1.0 depending on the design specification fo
6、r the service life (approximately40 years) in the operating environment of a nuclear spent fuel pool.1.5 A number of acceptable boron-based absorbing materials combinations are currently available while others are beingdeveloped for use in the future. This specification defines criteria essential an
7、d applicable to all materials combinations andidentifies parameters a buyer should specify to satisfy a unique or particular requirement.1.6 The scope of this specification does not comprehensively cover all provisions for preventing criticality accidents orrequirements for health and safety. Observ
8、ance of this specification does not relieve the user of the obligation to conform to allapplicable international, national, and local regulations.2. Referenced Documents2.1 ASTM Standards:2A240/A240M Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure
9、Vesselsand for General ApplicationsB209 Specification for Aluminum and Aluminum-Alloy Sheet and PlateC750 Specification for Nuclear-Grade Boron Carbide PowderC859 Terminology Relating to Nuclear MaterialsC1187 Guide for Establishing Surveillance Test Program for Boron-Based Neutron Absorbing Materia
10、l Systems for Use inNuclear Spent Fuel Storage RacksE105 Practice for Probability Sampling of MaterialsASTM Dictionary of Engineering Science and Technology2.2 ANSI Standards:3ANSI 45.2.2 Packaging, Shipping, Receiving, Storage and Handling of Items for Nuclear Power PlantsANSI-ASME NQA-1 Quality As
11、surance Requirements for Nuclear Facility Application2.3 U. S. Government Documents:4Title 10,10CFR50 Title 10, CFR, Energy Part 50 (10CFR50) Licensing of Production and Utilization FacilitiesTitle 10,10CFR72 Title 10, CFR, Energy Part 72 (10CFR72) Licensing Requirements for the Storage of Spent Fue
12、l in anIndependent Spent Fuel Storage Installation (ISFSI)1This specification is under the jurisdiction ofASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.03 on NeutronAbsorberMaterials Specifications.Current edition approved Feb. 15, 2006.1, 2011. Publis
13、hed March 2006.February 2011. Originally approved in 1983. Last previous edition approved in 19972006 asC99289(1997).C992 06. DOI: 10.1520/C0992-06.10.1520/C0992-11.2For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book
14、 of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3Available from the American National Standards Institute, 11 W. 42nd St., 13th Floor, New York, NY 10036.4Available from Superintendent of Documents, U. S. Government Printing Office, Washington,
15、DC 20402.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult
16、 prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3. Terminology3.1 Definitions of Terms
17、 Specific to This Standard:3.1.1 Terms shall be defined in accordance with Terminology C859 or the ASTM Dictionary of Engineering Science andTechnology, except as defined as follows:3.1.2 accelerated testinga procedure for investigating the potential for long-term changes in physical properties or c
18、hemicalcomposition of a material important to safety, caused by a system operating parameter such as temperature, chemical environmentor radiation.3.1.2.1 DiscussionThe procedure uses a value of the identified parameter that is outside the normal bound of the operatingparameter being investigated, i
19、n order to (1) increase the rate of degradation, if any, (2) identify the operating limit for acceptablelimit of the parameter, and (3) to provide information that might assist in interpreting the degradation mechanism(s) involved. Inthis manner, the long-term behavior of a material may be simulated
20、 in an appreciably shorter period of time.3.1.3 areal densitythe boron-10 per unit area of a sheet, which is equivalent to the mass per unit volume of boron-10 in thematerial multiplied by the thickness of the material in which that isotope is contained.3.1.4 buyerthe organization issuing the purcha
21、se order.3.1.5 individual piecea discrete section of neutron absorber material whose individual dimensions conform to those in thepurchase specification.3.1.6 irradiationthe incidence of neutron, gamma, and beta radiation from spent fuel assemblies on materials in a water-filledspent fuel pool.3.1.7
22、 production batcha group of neutron-absorbing material pieces produced in a continuous production period, all of whichcan be shown to have the same chemical composition, physical, and nuclear properties within specification limits.3.1.8 sellerthe neutron absorbing system manufacturer.3.1.9 service l
23、ifethe period of time for which properties of the neutron-absorbing material system are expected to remain incompliance with the contract requirements which relate to chemical and physical integrity.3.1.10 supplierany outside source of raw materials and services used by the seller.4. Ordering Inform
24、ation4.1 The buyer should specify a material for which there is documented evidence that the neutron absorbing material system iscapable of acceptable performance in the following environmental conditions to which the material is expected to be exposed:4.1.1Total service life of the neutron absorbin
25、g material system (considered forty years unless otherwise specified),4.1.1 Total service life of the neutron absorbing material system,4.1.2 Maximum integrated irradiation over the total service life of the neutron absorbing material system, and4.1.3 Chemical and thermal environment of the water in
26、 the spent fuel pool in which the neutron absorbing material system willbe located.4.2 The buyer shall specify the following physical and chemical properties of the neutron absorbing material system; this mayinclude archive or in-service surveillance coupons:4.2.1 Total quantity of individual pieces
27、 required,4.2.2 Physical dimensions of each individual piece required, and may also include physical form limitations including flatness,camber, bow, etc.,4.2.3 Boron-10 isotopic content of the neutron absorbing material system expressed in terms of grams of isotopic B-10 per cm2of surface area. Alt
28、ernatively, the boron-10 content may be specified by material density, the weight percent boron, minimumthickness, and the minimum acceptable weight fraction of boron-10 in the boron.4.2.4 Applicable tolerances for each dimension or property, including minimum boron-10 areal density.4.2.5 Material s
29、pecifications for the components of the neutron absorbing material system shall be in accordance withSpecifications A240/A240M, B209, and C750, if applicable.4.3 In addition to the properties of 4.2, the buyer shall specify the following system properties as required by the specific spentfuel storag
30、e rack design:4.3.1 Structural properties for the neutron absorbing material system, if required, and4.3.2 Limitations on gas evolution, product cleanliness, or other physical characteristics, if applicable.5. Material System Properties5.1 The boron-10 shall be uniformly distributed throughout the n
31、eutron absorbing material system as defined in 7.3 and 8.1.4.5.2 The neutron absorbing material system may contain, in addition to the boron or boron compound, any matrix materialsnecessary to maintain that boron in the state of specified uniformity and areal density throughout the stipulated servic
32、e life of thespent fuel storage system.5.2.1 The seller shall provide to the buyer a chemical analysis of the neutron absorbing material system, so that the buyer maydetermine the compatibility of the neutron absorbing material with the spent fuel storage rack and the pool environment.5.3 The seller
33、 shall provide the buyer with the elemental and boron isotopic composition of the neutron absorbing materialsystem and the particle size distribution when necessary of the boron compound so that the buyer may determine the neutronattenuating and absorbing properties of the material and its suitabili
34、ty for the buyers application.C992 1125.4 The loss of boron through any degradation mechanisms shall not lower the areal density below the allowable limits withinthe stated service life (see Section 6.1.1).5.5 It is recommended that in-service surveillance tests be performed to monitor the areal den
35、sity (see Guide C1187). It isfurther recommended that these tests determine both physical and performance characteristics. The physical tests should determineat least the size, weight, density, and surface appearances, including any surface blistering, delamination, or pitting. Theperformance tests
36、should determine at least the neutron attenuation capabilities and mechanical strength, if applicable. The testsamples should be positioned to maximize the irradiation doses the samples will receive during each exposure period. The beforeand after exposure test results should be compared to determin
37、e any unfavorable changes in the physical or performancecharacteristics.6. Test Documentation6.1 The seller shall provide to the buyer documentation of tests performed to characterize the neutron absorbing material systemperformance and mechanical properties.6.1.1 When appropriate, accelerated test
38、may be performed to demonstrate compliance to 5.4. The test reports shall include botha description of procedures and a review of results.6.2 The buyer shall determine the suitability of the neutron absorbing material system for the buyers application on the basisof accelerated test documentation an
39、d other evidence offered by the seller and by additional testing and evaluation performed bythe buyer.7. Sampling7.1 Sampling plans to meet acceptance criteria and inspection and measurement procedures that describe the method ofcompliance with this specification shall be established by the seller a
40、nd submitted to the buyer for approval prior to manufactureof the required product. The degree of sampling shall be specified by the purchase order. Practice E105 is referenced as a guide.7.2 Each sample taken shall be sufficient for quality control tests, acceptance tests, referee tests, and archiv
41、e samples asnecessary or desired by the buyer.7.3 To show uniformity of the boron-10, the seller shall demonstrate that the sampling for areal density is adequate forestablishing that the minimum boron-10 areal density is achieved throughout the product with a probability and confidenceapproved by t
42、he buyer.7.4 Archive samples shall be retained by the seller for a period of time specified by the buyer and delivered to the buyer uponrequest.8. Inspection8.1 Inspection of the neutron absorbing material shall be by production batch and by individual piece.8.1.1 Evaluation of chemical composition,
43、 density, areal density, and uniformity may be made on a production batch basis.8.1.2 Inspection of dimensions and physical form shall be made by individual piece.8.1.3 Inspection of the neutron absorbing material for defects and cleanliness (for example, any oils or foreign materials) shallbe perfo
44、rmed by individual piece.8.1.4 The boron-10 quantity and uniformity shall be determined. Determination may be determinedperformed by a neutronattenuation measurement or by a combination of isotopic analysis, chemical analysis, and physical measurements. The validity ofother techniques must be demons
45、trated.9. Rejection9.1 Items that fail to conform to the requirements of the specification may be rejected by the buyer. The seller may petition tothe buyer to waive the specifications for specific out-of-specification items. Decision to grant such waiver belongs to the buyer.The seller may also eff
46、ect any remedy to bring rejected items into specification providing he can demonstrate to the buyer that suchremedy does not impair the function or preclude the certification of the neutron absorbing material system.10. Certification10.1 When specified in the purchase order or contract, the seller s
47、hall prepare a certification that the neutron absorbing materialsystem was manufactured, sampled, tested, and inspected in accordance with the specifications and has been found to meet therequirements. When specifically required, testing results of the material shall accompany the certification. Eac
48、h certificationfurnished shall be signed by an authorized agent of the seller.11. Marking, Packaging, and Shipping11.1 For marking, packaging, and shipping, ANSI N45.2.2 is referenced as a guide. Each individual piece of neutron absorbingmaterial system shall be marked on one face in a location agre
49、ed upon by the buyer and seller with a serial identification traceableto the test analysis, production batch, and certification. The characters of the markings shall be of such size as to be clearly legible.The markings shall be sufficiently durable to withstand normal handling. The buyer shall approve the method of marking.11.2 The neutron-absorbing material shall be packaged for shipment in a suitable manner to assure that the material willnormally arrive in an undamaged conditionC992 11311.2.1 The buyer shall indicate to the seller unusual conditions of handli
