SKB to weld canisters for world’s first final repository

Swedish Nuclear Fuel and Waste Management Co., SKB, is to weld canisters for the Finnish final repository for spent nuclear fuel. An agreement has been concluded between SKB and its Finnish counterpart, Posiva Oy, under which SKB will weld the bases of the Finnish canisters. Work will start in 2025, and will be performed in SKB’s canister laboratory in Oskarshamn.

Magnus Holmqvist, CEO of SKB International AB

Magnus Holmqvist, CEO of SKB International AB

– We’ve been offering our services to sister organisations all over the world for many years. As Finland is using the final repository method developed by SKB, KBS-3, we’ve been sharing knowledge and experience with each other for a long time. This agreement gives us the opportunity to deliver a finished product. It will give us further experience in exporting the technology, knowledge and experience that SKB has developed over the past 40 years, says Magnus Holmqvist, CEO of SKB International AB.

Posiva recently completed its final repository in Onkalo and is awaiting a licence from its regulatory authority to start operating the facility. The company needs to weld bases for the canisters in which the spent nuclear fuel will be stored, so it turned to its colleagues in Sweden.

– This agreement sees us taking another step towards putting the world’s first final repository for spent nuclear fuel into operation. To be time-efficient, we chose to award the contract to SKB, which has successfully welded many canister bases. This means that we avoid additional costs, and we know that SKB will deliver high-quality work, says Ilkka Poikolainen, CEO of Posiva.

The agreement has been signed for five years, with an option for two more years. The work, which will be performed at the Canister Laboratory in Oskarshamn, is planned to start in 2025. The agreement covers the welding of approximately 160 canisters in total.

More information

Finland’s final repository will be built using the final repository solution for spent nuclear fuel that was developed in full by SKB in Sweden. The method is called KBS-3 and is based on three protective barriers: the copper canister that encloses the spent nuclear fuel, the clay buffer that surrounds the canister and protects against minor movements in the rock, and the Swedish bedrock to provide the outermost barrier. SKB and Posiva have been collaborating since 2001 to develop and test the method of final disposal.

SKB International

SKB International is a wholly-owned subsidiary of SKB, which provides services and expertise in the management and final disposal of nuclear waste and spent nuclear fuel based on the technology, know-how and experience developed in SKB’s programmes over the past 40 years. SKB International operates all around the world, with assignments in countries including Japan, South Korea, Taiwan, Norway and Germany. In total, SKB international has helped around 50 organisations around the world with knowledge and guidance on the management of nuclear waste and on SKB’s work to gain local acceptance.

More about welding technology

The welding method used is called friction welding, or more specifically friction stir welding, which has been specially adapted by SKB to weld copper. It is a mechanical welding technique with a rotating conical tool that is pressed into the joint between the parts to be welded. The material around the tool is heated by the friction and becomes soft. As the tool rotates, the copper material is stirred on both sides of the joint and binds the two metal parts together to form a homogeneous weld joint.

Published: 16 December 2024