Various types of cutting charges already exist, but mainly for cutting of few millimetres thick material. The research work will therefore focus on the development of a high performance cutting charge minimising the damages to surrounding structures for the dismantling of thick-walled steel components (ranging between 10 to 250 mm thickness), e.g. pipes, reactor pressure vessels.
The work will include studies and experiments at small and large scale, as well as a study to possibly eliminate or minimise undesired secondary effects caused by the projection of splinters at high speed.
Specific data will be produced on costs, work time and secondary waste arisings from the application of this steel cutting technique. It is expected that the project will result in an economical and dose-rate tolerant cutting technique particularly suitable for dismantling work in inaccessible places.
In the countries of the European Union the presence of a substantial number of nuclear installations out of operation, requires an organisational and technological effort to tackle the problem of their decommissioning. OTO Melara (Italy) has proposed, in the frame of the CEC programme of decommissioning (1989-1993) - Contract n°FI2D-0010, the use of explosive techniques as suitable means to dismantle nuclear installations. Such techniques are promising, because of their easy application and reduced costs, coupled with a very high cutting efficiency.
The explosive techniques are proposed for cutting steel plates up to the typical thickness of nuclear power reactor vessels. This work is therefore focused on the development of a high performance cutting charge, minimising at the same time the spread of contamination and eliminating as far as possible undesiderable secondary effects caused by the projection of fragments at high speed.
The final objective is to optimise a technique for cutting big structures with low costs and limited occupational radiation doses.