Demolishing large radioactively contaminated vessels or shielding - by internal blasting explosion after walls have been weakened by local cutting charges

摘要

Thick-walled vessels esp. reactor vessels, heat exchangers and shielding structures of cast iron or concrete, which have become radio actively contaminated, are broken by first notching or weakening the vessel wall by cutting charges and then producing an internal pressure by an internal charge to force the notched structure apart. This internal bursting pressure may be produced by a flexible explosive, a liq. explosive or damped explosive in the latter case, a liq. such as water or plastics foam may be used for tamping. The min. access to radioactive zones is required for demolition. The arrangement of the initial, external charges can be varied to suit the thickness and strength of the structure.