ASTM C753-16a(R2021) pdf free download

ASTM C753-16a(R2021) pdf free download.Standard Specification for Nuclear-Grade, Sinterable Uranium Dioxide Powder
1. Scope
1.1 This specification covers nuclear-grade, sinterable UO 2 powder. It applies to UO 2 powder containing uranium (U) of any 235 U concentration in the production ofnuclear fuel pellets for use in nuclear reactors. 1.2 This specification recognizes the presence of repro- cessed U in the fuel cycle and consequently defines isotopic limits for commercial grade UO 2 . Such commercial grade UO 2 is defined so that, regarding fuel design and manufacture, the product is essentially equivalent to that made from unrepro- cessed U. UO 2 falling outside these limits cannot necessarily be regarded as equivalent and may thus need special provisions at the fuel fabrication plant or in the fuel design. 1.3 This specification does not include provisions for pre- venting criticality accidents or requirements for health and safety. Observance of this specification does not relieve the user of the obligation to be aware of and conform to all international, national, or federal, state, and local regulations pertaining to possessing, shipping, processing, or using source or special nuclear material. 1.4 This specification refers expressly to UO 2 powder be- fore the addition of any die lubricant, binder, or pore former. If powder is sold with such additions or prepared as press feed, sampling procedures, allowable impurity contents, or powder physical requirements may need to be modified by agreement between the buyer and the seller.1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.7 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
4. Chemical Composition
4.1 Uranium Content—The U content shall be determined on a basis to be agreed upon between the buyer and seller. 4.2 Oxygen-to-Uranium Ratio (O/U)—The O/U ratio may be specified as agreed upon between the buyer and seller. The determination of the O/U ratio shall be in accordance with Test Methods C696 or a demonstrated equivalent. 4.3 Impurity Content—The impurity content shall not ex- ceed the individual element limit specified in Table 1 on a U basis. Total non-volatile oxide impurity content (see Table 1 and other impurity elements not having associated limits in Table 2) shall not exceed 1500 µg/gU. Some other elements such as those listed in Table 2 may also be of concern for the buyer and should be measured and reported if requested. If an element analysis is reported as “less than” a given concentration, this “less than” value shall be used in the determination of total impurities. Impurity elements measured and their associated limits may differ from what is listed in this specification agreed upon between the buyer and seller. 4.4 Moisture Content—The moisture content shall not ex- ceed 0.50 weight percent of the powder. 4.5 Isotopic Content: 4.5.1 For UO 2 powder with an isotopic content of 235 U below 5 %, the isotopic limits of Specification C996 shall apply, unless otherwise agreed upon between the buyer and the seller. If the 236 U content is greater than Enriched Commercial Grade UF 6 requirements, the isotopic analysis requirements of Specification C996 shall apply. The specific isotopic measure- ments required by Specification C996 may be waived, pro- vided that the seller can demonstrate compliance with Speci- fication C996, for instance, through the seller’s quality assurance records. 4.5.2 For UO 2 powder that does not have an assay in the range set forth in 4.5.1, the isotopic requirements shall be as agreed upon between the buyer and the seller. 4.6 Equivalent Boron Content—For thermal reactor use, the total equivalent boron content (EBC) shall not exceed 4.0 µg/g on a U basis. For purpose of EBC calculation B, Gd, Eu, Dy, Sm, and Cd shall be included in addition to elements listed in Table 1. The method of performing the calculation shall be as indicated in Practice C1233. For fast reactor use, the above limitation on EBC does not apply.