Session: OAC-04-01 Storage and Transportation of Radioactive Materials-1

Paper Number: 122598

122598 - Transport of Large Nuclear Power Plant Components – New Sco-Iii Regulations and Mechanical Design Assessment 

The decommissioning or refurbishment of nuclear facilities necessitates either the storage or disposal of large radioactive components such as steam generators, pressurizers, reactor pressure vessels and heads, and coolant pumps, to list the major contributors. These components or objects are large in size and mass, measuring up to approximately 6 meters in diameter, up to 20 meters in length, and weighing over 400 000 kg. In many situations, the components are transported off-site to a storage, disposal or recycling/treatment facility. Previously, many large objects had to be transported under special arrangement.

The latest 2018 edition of the International Atomic Energy Agency (IAEA) Regulations for the Safe Transport of Radioactive Material, No. SSR-6, incorporates regulations for the shipment of contaminated, but not activated large objects as a new category of surface contaminated object, SCO-III, based on the IAEA “performance package” concept.

This paper provides background and practical guidance on these regulations. Additionally, first experiences with SCO-III in the approval process are presented. 

 

For SCO-III components a mechanical assessment regarding the tests specified in the transport regulations SSR-6 for demonstrating ability to withstand normal conditions of transport is required - a free drop of the package onto an unyielding target and a penetration test have to be investigated. Large components are unique objects; therefore, it is not possible to choose experimental testing as assessment method. The application of a complex numerical analysis for mechanical proof is necessary.

The assessment of the loads takes place based on local stress distributions.

The large nuclear components have typically been transported in an unpackaged manner, so that the external shell of the component provides the containment wall.

The paper will represent the methods, which are used for the evaluation of the mechanical integrity of the object for transport approval.

Presenting Author: Steffen Komann BAM

Presenting Author Biography: Studies in civil Engineering with specialisation in engineering mechanics and PhD in the field of stability of light weight steel constructions including material investigations and numerical analyses.

Several years experience in design assessment of transport casks for radioactive materials and licensing of large nuclear power plant component transports, steering for drop tests and numerical analysis at the Federal Institute for Materials Research and Testing in Berlin, Germany.

Now responsible for the section “Safety assessment of transport casks for radioactive material”.

Authors:

Steffen Komann BAM
Frank Wille BAM
Konrad Linnemann BAM
Jeff Ramsay CNSC
Ingo Reiche BASE