Applicability examination and evaluation of nuclear reactor dismantlement technology in the FUGEN Examination of simulation material cutting by abrasive water jet, 2

Nakamura, Yasuyuki ; Morishita, Yoshitsugu ; Kikuchi, Koichi; Usui, Tatsuo*; Ogane, Daisuke*

As a peculiar issue of the decommissioning of FUGEN, it is necessary to establish a dismantlement method for the reactor having a 224 double-tubes structure arranged with pressure and calandria tubes concentrically. Mechanical cutting method will be desirable considering the influence on the atmospheres because the double-tubes consist of highly activated zirconium alloy and zircalloy material. Therefore, the abrasive water jet method was tested and examined as a mechanical double-tube cutting method that needs the standoff comparatively longer. We confirmed the applicability of the abrasive water jet method to the dismantlement of FUGEN's reactor. According to this cutting test, it is possible to cut slab at ca. 0.3-0.6kg/min of abrasive supply. (abrasive supply of AWJ is generally ca. 1.5-2.0kg/min.) And, 150mm thick of SUS were able to cut in the water by once.