Architecture and management of a geological repository - Andra

9 – Nuclear operating resources in the repositoryFigure 9.2.5Koepe pulley of the WIPP packages descent shaft (USA)The safety of the equipment described above is ensured by four independent devices:- A disc brake braking system acting directly on the Koepe pulley. These brakes are activated bytwo independent circuits, one to ensure the role of static service brake and the other the function ofdynamic safety brake.- An anti-fall system, independent of the previous system, which can bring the cage to a halt onspecific cables suspended from the surface superstructure to the bottom of the shaft.- Two arrestor systems installed in the tower and under the bottom station can stop the cage if itexceeds its normal course. They work by deforming metal sections that thereby absorb the cage'skinetic energy.- Finally a passive fall shock absorbing system, installed in lower part of the shaft (see section11.7), could complete these arrangements. Such a system could be justified in the very unlikelycase when none of the first three systems were capable of stopping the cage's course.The first three systems have been proven to be reliable systems in mining installations over manyyears. Moreover the fall shock absorbing system has been used in many industrial applications fromvehicle crashes, high-speed trains and missile impacts. However the anti-fall and fall bufferingsystems require further studies because of the weight that is transported.DOSSIER 2005 ARGILE -ARCHITECTURE AND MANAGEMENT OF A GEOLOGICAL DISPOSAL SYSTEM341/495