Reactor pressure vessel dismantling system by arc saw cutting technique

Upon dismantling a reactor pressure vessel since the exposure does is high, operation has to be conducted by remote control while taking an appropriate distance from the operation place to the cutting position in view of reducing the operator's dose. A saw blade is set to an optional position in a reactor pressure vessel by an arc saw head-support driving mechanism, a mast fixing device and a device for moving the arc saw head portion vertically, circumferentially and radially, thereby cutting the reactor pressure vessel. The cutting pieces are taken out, conveyed and contained in a container. Replacing operation for abraded saw blade is conducted by remote control to make the operation efficient and reduce the operator's radiation dose. Dross and gases generated upon cutting are recovered and the nuclear pressure vessel dismantling can be conducted safely and efficiently. (N.H.)