Underwater Leak Mitigation of Spent Fuel Pool Liners and Undrainable TanksAREVA’s Adhesive Technology

Proven adhesive bondings qualifi ed to provide

solutions for underwater repairs

Leakages of stainless steel pool liners like spent fuel pools (SFP) or any other permanent with water fi lled tanks can be caused by several reasons: mechanical impact, mechanical or heat stress, weld failure and corrosion. Long-time experience proves that corrosion is the main reason for leakages, especially stress corrosion cracking (SCC). Usually, SCC occurs near the welding line in the heat aff ected zone.

To seal such leakages, or as a preventive measure, AREVA has developed the AREVA EP UW process. It was specially designed to meet the requirements for undrainable stainless steel pools and tanks in the nuclear industry.

The main advantages of the AREVA process are:

• Application with diver or remote-controlled manipulator is possible• The process can be applied in narrow gaps, e.g. between the fuel racks and the spent fuel pool walls• The deployed manipulator can be easily adjusted to the application area• No new heat aff ected zones arise (compared to welding repair).

Underwater manipulators corner type

AREVA EP UW process: two-component epoxy adhesive

Main characteristics:• Temperature resistant up to 60°C (permanent) or 80°C (1 week)• Radiation resistant up to 20 MGy• Chemically inert to demineralized water, river water, sea water, borated water (3,000 ppm)• No leeching of detrimental elements to surrounding media• Good decontaminability• Very high adhesion force

Regardless of the origin of the leak, the so-called “sandwich technology” is used to seal leakages with the epoxy adhesive. This highly durable bonding system fulfi lls two purposes:• Sealing the leak area with the adhesive material• Install a protective stainless steel cover plate.

The cover plate prevents the liner and the bonding material from mechanical damage.

Installed rail system in a SFP corner

Underwater Leak Mitigation of Spent Fuel Pool Liners and Undrainable Tanks

AREVA’s Adhesive Technology: a proven solu-tion to close existing leaks or prevent future leaks in stainless steel pools

If applicable, a leak detection can be performed to identify the leaks beforehand and repair only af-fected locations. Nevertheless, all susceptible areas can be treated without leak detection.

The material used has been approved by European and Japanese authorities.

For more than 25 years of global fi eld application no leakage of a repaired area has been reported

SFP corner after installation of repair plates

Your benefi ts at a glance • Cost- and time-eff ective repair method, compared to welding repair

• Sophisticated areas with limited access in high radiation areas can be repaired

• Adaptation to a wide variety of possible application areas due to the use of a fl exible and extendable manipulator system

• Product has been approved by European and Japanese authorities

• Existing material structure is not aff ected by the repair

AREVA GmbHYour contact: chemistry-services@areva.com

Scheme of the underwater manipulator system in a SFP corner

Editor and Copyright 2016: AREVA GmbH – Paul-Gossen-Straße 100 – 91052 Erlangen, Germany. It is prohibited to reproduce the present publication in its entirety or partially in whatever form without prior written consent. Legal action may be taken against any infringer and/or any person breaching the aforementioned prohibitions.

Subject to change without notice, errors excepted. Illustrations may diff er from the original. The statements and information contained in this publication are for advertising purposes only and do not constitute an off er of contract. They shall neither be construed as a guarantee of quality or durability, nor as warranties of merchantability or fi tness for a particular purpose. These statements, even if they are future-orientated, are based on information that was available to us at the date of publication. Only the terms of individual contracts shall be authoritative for type, scope and characteristics of our products and services. Status: October 2016 G-164-V3-13-ENGPB