Download or read book Use of Subsize Specimens for Determination of Radiation Embrittlement of Operating Reactor Pressure Vessels written by AD. Amayev and published by . This book was released on 1993 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents groundwork for determining the ductile-to-brittle transition temperature (DBTT) from subsize specimens (5 by 5 by 27.5 and 3 by 4 by 27.0 mm) and describes the correlation between the DBTT obtained from tests of standard Charpy specimens and subsize specimens. A method for taking samples from the inside surface of reactor pressure vessels and fabricating small specimens from them was developed in the USSR. This method is used to assess the effectiveness of pressure vessel recovery by annealing. Some results of the DBTT evaluation for the base and weld metal before and after recovery are given.

Download or read book Application of Subsize Specimens for Irradiation Embrittlement Monitoring of VVER 440 213 RPV Steels written by A. V. Nikolaeva and published by . This book was released on 2008 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of VVER-440/213 reactor pressure vessel (RPV) surveillance specimens studies showed that all surveillance impact bend specimens were irradiation with a lead factor more than 20 compared to irradiation of the pressure vessel inner surface. This is a special problem of radiation embrittlement assessment for VVER-440/213 RPV materials. Prediction of radiation embrittlement of RPV materials using surveillance specimens is efficient on the basis of accelerated irradiation compared to irradiation of the RPV inner surface. However, the lead factor, which is the ratio of neutron flux affecting surveillance specimens to neutron flux affecting the RPV inner surface in the maximum irradiated zone, should be not too high, when acceleration of steel irradiation would not cause qualitative changes in physical processes of irradiation damage. It is generally assumed that irradiation with a lead factor less than 3-6 provides adequate assessment of radiation embrittlement dependence on the damage dose. In the top part of the chains with VVER-440/213 surveillance specimens, fast neutron flux decreases ~20 times and the top capsules are irradiated with a neutron flux range close to the flux maximum on the inner surface of the reactor pressure vessel; i.e., the lead factor there is around 1. This concerns both reactors with full core and with dummies on the periphery of the core. The gradient of the neutron flux in the top and bottom parts of chains is great enough; hence, the volume of homogeneously irradiated metal is low. However, there is an opportunity to use material from the top capsules of irradiation sets for correct evaluation of the transition temperature using subsize specimens. As surveillance specimens in the top capsules are irradiated at the same conditions as the pressure vessel, their study allows precise determination of radiation embrittlement of RPV materials. The results of studies of irradiation embrittlement of VVER-440/213 RPV steels using subsize specimens are discussed.

Download or read book Radiation Embrittlement of Nuclear Reactor Pressure Vessel Steels written by Lendell E. Steele and published by ASTM International. This book was released on 1993 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiation Embrittlement and Surveillance of Nuclear Reactor Pressure Vessels An International Study written by L. E. Steele and published by ASTM International. This book was released on 1983 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiation Embrittlement of Nuclear Reactor Pressure Vessel Steels written by Lendell E. Steele and published by ASTM International. This book was released on 1986 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Guidelines for Prediction of Irradiation Embrittlement of Operating WWER 440 Reactor Pressure Vessels written by International Atomic Energy Agency and published by IAEA. This book was released on 2005 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: The IAEA International Database on RPV Materials (IDRPVM) is used for prediction and analysis of radiation embrittlement of WWER-440 reactor pressure vessel (RPV) materials. These guidelines will be used for assessment of irradiation embrittlement of RPV ferritic materials as a result of degradation during operation.

Download or read book Small Specimen Test Techniques Applied to Nuclear Reactor Vessel Thermal Annealing and Plant Life Extension written by W. R. Corwin and published by ASTM International. This book was released on 1993 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Using Subsize Impact Bend Specimens for Estimation of Irradiation and Re Irradiation Embrittlement of VVER RPV Steels written by A. V. Nikolaeva and published by . This book was released on 2008 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of impact bend tests of subsize Charpy V-notch-type (CVN) specimens are used in Russia for monitoring both re-irradiation embrittlement of the first generation of VVER-440 (including VVER-440/179 and VVER-440/230, i.e., projects B-179 and B-230) reactor pressure vessel (RPV) steels and irradiation embrittlement of VVER-440/213 RPV steels. For the first generation of VVER-440 RPVs, no surveillance program was foreseen and only subsize specimens (5 by 5 by 27.5 mm and 3 by 4 by 27 mm) can be manufactured from samples taken from the inner surface of the RPV for radiation embrittlement monitoring. For VVER-440/213 RPVs, 80 % of the surveillance specimens are irradiated with a lead factor greater than 20. Only four specimens of base metal and four specimen halves of weld seam material are irradiated with a lead factor less than 3. Taking into account that full-size (10 by 10 by 55 mm) CVN specimens were used in surveillance programs, using subsize specimens enables to solve the flux effect problem for VVER-440/213 RPV beltline materials and ensure representativity of surveillance programs. Application of subsize specimens for the estimation of radiation embrittlement requires developing a correlation between transition temperature values evaluated using test results of standard (full-size) and subsize CVN specimens. Such a correlation is discussed.

Download or read book Small Specimen Test Techniques written by W. R. Corwin and published by ASTM International. This book was released on 1998 with total page 630 pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of an increasing interest in radiation embrittlement for aging nuclear reactors, scientists gathered in New Orleans in January 1997 to consider the interests and capabilities of the scientific-testing community and of the commercial light-water-cooled power-reactor industry in terms of improving methods to characterize component integrity. The resulting 37 papers concentrate on the use of unique small and miniature specimens; nondestructive, nonintrusive, and in- situ test techniques for measuring mechanical and fracture properties; the application of tests to irradiation-induced embrittlement; and actual examples of tests to determine material integrity and to evaluate potential component life extension. They consider experimental, analytical, and computational aspects. Annotation copyrighted by Book News, Inc., Portland, OR

Download or read book Radiation Embrittlement of Nuclear Reactor Pressure Vessel Steels written by Lendell E. Steele and published by ASTM International. This book was released on 1986 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Application of the Reconstituted Subsize Specimens for Assessment of Irradiation Embrittlement of RPV Steels written by YI. Shtrombakh and published by . This book was released on 2002 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The actual values of the weld metal characteristics required for determination of the RPV lifetime, that is the ductile-to-brittle transition temperature (DBTT) in the unirradiated condition (Tk0), the phosphorus and copper contents (that are known to affect the radiation stability of steel), were not measured during manufacturing of old VVER-440 reactors. The small samples (templets) were cut out of the inside surface of the old Russian VVER-440 reactor pressure vessels (RPV) to assess the actual condition of the RPV material before and after post-irradiation annealing and after re-irradiation. Calculations have shown that it is not admissible to cut out samples of the size appropriate for machining of fullsize Charpy specimens necessary to comply with Russian Guide for determination of RPV steel DBTT. An application of subsize specimens for estimation of irradiation embrittlement of RPV steel was substantiated. In order to substantiate application of reconstituted subsize specimens made from broken subsize specimens for assessment of irradiation embrittlement of RPV materials, the correlation dependencies between the DBTT values of reconstituted and standard subsize specimens were developed. With this aim reconstitution of broken 5x5x27.5 mm specimens was performed by the stud-welding method. Both unirradiated and irradiated to high fluence steels were used in this program. The influence of reconstitution on the correlation dependence of DBTT for standard fullsize and subsize impact specimens was studied. Irradiation and re-irradiation kinetics of RPV steels were studied using subsize specimens machined from templets of operating units.

Download or read book The Actual Properties of WWER 440 Reactor Pressure Vessel Materials Obtained by Impact Tests of Subsize Specimens Fabricated Out of Samples Taken from the RPV written by YN. Korolev and published by . This book was released on 1998 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents the results of a study on degradation due to irradiation occurring in WWER-440 reactor pressure vessel (RPV) steel, using subsize Charpy specimens (5x5x27.5 mm3). An application of subsize specimens for estimation of irradiation embrittlement of RPV steel has been substantiated. Comparison between ductile-to-brittle transition temperatures (DBTT) for full-size and subsize Charpy specimens has been carried out. The relation between these two values has been clarified. The results of testing trepans and templates cut out from WWER-440 reactor pressure vessels are considered. The main results of the program TACIS-91/1.1. are discussed.

Download or read book Small Specimen Test Techniques written by ASTM International Committee E10 on Nuclear Technology and Applications and published by ASTM International. This book was released on 2002 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiation Embrittlement of Nuclear Reactor Pressure Vessel Steels written by Lendell E. Steele and published by ASTM International. This book was released on 1989 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Subsize Specimen Testing of a Nuclear Reactor Pressure Vessel Material written by NS. Cannon and published by . This book was released on 1994 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new methodology is proposed to correlate the upper shelf energy (USE) of full size and subsize Charpy specimens of a nuclear reactor pressure vessel plate material, A533B. The methodology appears to be more satisfactory than the methodologies proposed earlier. USE of a notched-only specimen is partitioned into macro-crack initiation and crack propagation energies. USE of a precracked specimen provides the crack propagation energy. AUSE, the difference between the USE of notched-only and precracked specimens, is an estimate of the crack initiation energy. AUSE was normalized by a factor involving the dimensions of the Charpy specimen and the plastic stress concentration factor at the notch root. The normalized values of AUSE were found to be invariant with specimen size.

Download or read book A Wide Range Embrittlement Trend Curve for Western Reactor Pressure Vessel Steels written by Mark Kirk and published by . This book was released on 2013 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Embrittlement trend curves (ETCs) are used to estimate the magnitude of neutron irradiation embrittlement as a function of both exposure (fluence, flux, temperature, ...) and composition (copper, nickel, manganese, phosphorus, silicon, ...) variables. ETCs provide information needed to assess the structural integrity of operating nuclear reactors, and to determine their suitability for continued safe operation. ETCs may use any of a number of different metrics (e.g., ?T41J, ?YS, ?To) to quantify the magnitude of embrittlement, and may use data from a number of different sources (e.g., commercial power reactors, material test reactors). Past efforts on ETC development in the United States have used data drawn from domestic licensees. For example, the ETCs in Regulatory Guide 1.99 Revision 2 and 10 CFR 50.61a were based on ?T41J data from Charpy specimens tested as part of licensee surveillance programs [RG199R2 Regulatory Guide 1.99, "Radiation Embrittlement of Reactor Vessel Materials," Rev. 2, U.S. Nuclear Regulatory Commission, Washington, DC, May 1988 and 10CFR5061a Title 10, Section 50.61a, of the Code of Federal Regulations, "Alternative Fracture Toughness Requirements for Protection against Pressurized Thermal Shock Events," promulgated Jan 4, 2010.]. While this approach has addressed past needs well, future needs such as power uprates, license extensions to 60 years and beyond, and the use of low copper materials in new reactors produce future operating conditions for the U.S. reactor fleet that may differ from past experience, suggesting that data from sources other than licensee surveillance programs may be needed. While data for these conditions is currently available, it is mostly quantified using embrittlement metrics other than ?T41J, and it arises mostly from sources other than the U.S. surveillance program. This paper draws together embrittlement data expressed in terms of ?T41J and ?YS from a wide variety of data sources as a first step in examining future embrittlement trends. This evidence supports development of a "wide range" ETC based on a collection of over 2500 data. The paper includes an assessment of how well this ETC models the whole database, as well as significant data subsets. Comparisons presented herein indicate that a single algebraic model, denoted WR-C(5), represents reasonably well both the trends evident in the data overall as well as trends exhibited by the following four data subsets: ?T30 data from the U.S. surveillance program, ?T30 data from non-U.S. surveillance programs, ?T30 data from test reactor irradiations, and ?YS data from test reactor irradiations. Of particular importance, the WR-C(5) model indicates the existence of trends in high fluence data (? > 2-3 x 1019 n/cm2, E > 1 MeV) that are not as apparent in the U.S. surveillance data due to the limited quantity of ?T30 data measured at high fluence in that dataset. Additionally, WR-C(5) models well the trends in both test and power reactor data despite the fact it has not term to account for flux. While the appropriateness of using data from such a variety of sources to inform a trend curve is debated by the technical community, it is suggested that one appropriate use of the WR-C(5) trend curve may include the design irradiation studies to validate or refute the findings presented herein. Additionally, WR-C(5) could be used, along with other information (e.g., other trend curves, theoretical expectations, plant-specific data, etc.), as one tool to predict irradiation trends pending the availability of confirmatory data in the high fluence régime.

Download or read book Status of USA Nuclear Reactor Pressure Vessel Surveillance for Radiation Effects written by Lendell E. Steele and published by ASTM International. This book was released on 1983 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: