Table of Contents ECNDT '98
Session: Nuclear Industry
Advanced NDT of Primary Circuit Components of WWER NPPsP. Trampus* - International Atomic Energy Agency, Austria
D. Corak - INETEC, Croatia
*Corresponding Author Contact:
|TABLE OF CONTENTS|
In the countries of Central and Eastern Europe and of the former Soviet Union there are 45 WWER type (Water Cooled Water Moderated Power Reactor) nuclear power units in operation and, in addition, 11 units of the same type under construction. The total installed gross capacity of the operating units is 31,000 MW(e). Detailed data are summarised in Table1. Reliable generation of electricity from these nuclear power plants (NPPs) is vital to the economies of these countries, particularly during the transition from the centrally planned to the market oriented economy.
Safe and reliable operation of these WWER NPPs requires, among others, the assessment of structural integrity of the main components. One of the most important elements of assessing structural integrity is In-Service Inspection (ISI), the results of which deliver information concerning components' condition. Visual, surface or volumetric examinations are performed during these inspections. Usage of advanced non-destructive testing (NDT) methods and techniques are essential for detecting and sizing flaws as an input for the component integrity assessment.
The main problem of the WWER operators is that the supplier did not provide appropriate methodology, criteria and equipment for planning, organisation and implementation of the ISI activity of these plants. The countries in the region have had to develop their own capabilities. These reflect the existing differences among their economic, financial and social conditions.
According to its mandate, the International Atomic Energy Agency (IAEA) is authorised to make provisions for materials, services, equipment and facilities to meet the needs of research on, and development and practical application of, atomic energy for peaceful purposes, including the production of electric power, with due consideration for the needs of developing areas of the world. The assistance is provided to the developing Member States of the IAEA through the Technical Co-operation (TC) programme, which is composed of national, regional and interregional projects. The elements of TC project activities are expert services (field missions, workshops, seminars, national consultants' visits), provision of essential hardware and software, training (fellowships, scientific visits and group training) and sub-contracts. Projects, which have to meet strict criteria to be accepted by the IAEA, are created on the basis of requests from developing Member States, assisted by IAEA staff to the extent desired by Member States. TC projects are financed entirely from the voluntary contributions of developed and developing Member States.
|Country||Nuclear power unit||Reactor type||Status|
|Armenia||Armenia-2||440 Model 230||In Operation|
|Bulgaria||Kozloduy-1||440 Model 230||In Operation|
|Kozloduy-2||440 Model 230||In Operation|
|Kozloduy-3||440 Model 230||In Operation|
|Kozloduy-4||440 Model 230||In Operation|
|Kozloduy-5||1000 Model 320||In Operation|
|Kozloduy-6||1000 Model 320||In Operation|
|Czech Republic||Dukovany-1||440 Model 213||In Operation|
|Dukovany-2||440 Model 213||In Operation|
|Dukovany-3||440 Model 213||In Operation|
|Dukovany-4||440 Model 213||In Operation|
|Temelin-1||1000 Model 320||Under Construction|
|Temelin-2||1000 Model 320||Under Construction|
|Hungary||Paks-1||440 Model 213||In Operation|
|Paks-2||440 Model 213||In Operation|
|Paks-3||440 Model 213||In Operation|
|Paks-4||440 Model 213||In Operation|
|Russian Federation||Balakovo-1||1000 Model 320||In Operation|
|Balakovo-2||1000 Model 320||In Operation|
|Balakovo-3||1000 Model 320||In Operation|
|Balakovo-4||1000 Model 320||In Operation|
|Kalinin-1||1000 Model 338||In Operation|
|Kalinin-2||1000 Model 338||In Operation|
|Kalinin-3||1000 Model 320||Under Construction|
|Kola-1||440 Model 230||In Operation|
|Kola-2||440 Model 230||In Operation|
|Kola-3||440 Model 213||In Operation|
|Kola-4||440 Model 213||In Operation|
|Novovoronezh-3||440 Model 230||In Operation|
|Novovoronezh-4||440 Model 230||In Operation|
|Novovoronezh-5||1000 Model 187||In Operation|
|Slovak Republic||Bohunice-1||440 Model 230||In Operation|
|Bohunice-2||440 Model 230||In Operation|
|Bohunice-3||440 Model 213||In Operation|
|Bohunice-4||440 Model 213||In Operation|
|Mochovce-1||440 Model 213||Under Construction|
|Mochovce-2||440 Model 213||Under Construction|
|Mochovce-3||440 Model 213||Under Construction|
|Mochovce-4||440 Model 213||Under Construction|
|Ukraine||Khmelnitski-1||1000 Model 320||In Operation|
|Khmelnitski-2||1000 Model 320||Under Construction|
|Khmelnitski-3||1000 Model 320||Under Construction|
|Khmelnitski-4||1000 Model 320||Under Construction|
|Rovno-1||440 Model 213||In Operation|
|Rovno-2||440 Model 213||In Operation|
|Rovno-3||1000 Model 320||In Operation|
|Rovno-4||1000 Model 320||Under Construction|
|South Ukraine-1||1000 Model 302||In Operation|
|South Ukraine-2||1000 Model 338||In Operation|
|South Ukraine-3||1000 Model 320||In Operation|
|Zaporozhe-1||1000 Model 320||In Operation|
|Zaporozhe-2||1000 Model 320||In Operation|
|Zaporozhe-3||1000 Model 320||In Operation|
|Zaporozhe-4||1000 Model 320||In Operation|
|Zaporozhe-5||1000 Model 320||In Operation|
|Zaporozhe-6||1000 Model 320||In Operation|
Recognising the high priority of the ISI and NDT related issues, various national and regional TC projects have been being implemented during the last decade. The necessity to improve the overall level of ISI and to use advanced NDT methods have been emphasised repeatedly by the representatives of Member States in the Europe region. In addition, the Government of Croatia has offered the country's capability (equipment of its facilities and experience on WWER-440/1000 ISI activities) to support the Europe regional activity. After detailed discussions with the representatives of the Member States in question, the IAEA has approved the TC regional project for Europe on 'Advanced NDT of Primary Circuit Components of WWER NPPs' for the years 1997 to 1999. An amount of around US$ 300,000 has been foreseen as project core budget. Countries participating in the project activity are Armenia, Bulgaria, Croatia, Czech Republic, Hungary, Russian Federation, Slovak Republic and Ukraine.
The overall goal of the regional project on 'Advanced NDT of Primary Circuit Components of WWER NPPs' is to improve the safety, reliability and availability of WWERs through ISI using advanced NDT. The main objectives of the project have been defined as follows:
The main inputs and resources to the project are
The expected outputs of the project are
In the year 1997, according to the project work plan, two one-week regional workshops were held. Both were hosted by the company INETEC, Zagreb, Croatia. The topics of these workshops were:
The participants of these workshops have been representatives of utilities/NPPs, ISI vendors and regulatory authorities from the countries of the Europe region. The workshops have been structured to experts' presentations, national reports provided by the participants, round table discussions and demonstration of NDT techniques. Experts were selected from Germany, who represented the European Union (EU) as well, Russian Federation (only for the first workshop), the United States and from the host country. The national reports reflected the status and pointed out strengths and weaknesses (problematic areas) of the subject area in the participating countries.
The main topics of the workshop on Basic Elements of ISI Programme Planning and Implementation were as follows:
On the basis of the national reports and taking into account the Russian Federation experts' presentations, it could be stated that the technical level of ISI on the primary circuit components has developed in some of the countries in the region. Also some countries started to prepare and issue the rules for ISI planning and implementation. The level, completion and force of these national documents are, however, different. The aspect common within them is the elements of the original Russian documents (PK 1514-72 or PNAE G-7-008-89) and that of the ASME Code Section XI have been merged.
The main topics of the workshop on Performance Demonstration of UT and ET Systems covered the following:
Although the title of the workshop was Performance Demonstration, its scope covered each major component of the inspection qualification process of ISI systems. Special interest has been shown by the representatives of the region's countries with regard to the criteria to establish a national Qualification Body, and the possibility of the establishment of joint Qualification Body was also considered. The role and importance of technical justification have been discussed thoroughly. In this regard, the results of which areas of technical justification experience from the EU can be used without additional efforts, need further adaptation activity, and cannot be used by the WWER NPPs, were also investigated.
In most of the countries of the Europe region, new atomic laws are in force. As a consequence of this, renewing the legal systems is in progress that means new ordinances, nuclear codes, non-mandatory guides etc. In the second and third level of the countries' legal systems there seems to be divergence which does not make any joint activity on inspection qualification easy. However, sharing resources is considered desirable for the efficient usage of regional resources.
A brief survey of the current status of ISI practices in the Europe region shows that while there are variations in the progress of establishment national qualification infrastructures, there are generally encouraging signs. A common basis is emerging in some countries in the use of the 'Methodology for Qualification of In-Service Inspection Systems for WWER Nuclear Power Plants' recently issued by the IAEA. However, much more still needs to be done and assistance in the transfer of the technologies and know-how remains of a high safety priority.
Based on discussions with experts and representatives of the participating Member States during the project implementation, the following topical issues were identified for further consideration:
Certain Member States of the IAEA (France, Spain, USA) have expressed their interest in and willingness to support the project activity and the project could be upgraded by any of them. If this would be situation, the experience of these countries, for example, on preparation of administrative procedures, know-how of development of technical basis for various activities, database of trials, etc. could more easily be transferred to the region.