Fuel assembly for SFR nuclear reactor, comprising housing containing removably fastened upper neutron shielding device

A fuel assembly for a nuclear reactor comprises a housing of longitudinal axis (X) having a central section containing nuclear-fuel pins and an upper section, forming a portion of the head of the assembly, containing a upper neutron shielding device (NSD) including neutron absorbers and means for reversibly interlocking with the housing and a moveable weight forming the head of the NSD, which is mounted so as to be able to move translationally relative to the rest of the NSD over a given path. The interlocking means is configured so that the NSD and the housing can be interlocked and uninterlocked by moving the moveable weight along the longitudinal axis by means of a grapple for extraction of the NSD, the claws of this grapple engages with the moveable weight and the rest of the NSD is in downward longitudinal abutment in the interior of the housing. 用于核反应堆的燃料组件，包括纵向轴线(X)的外壳，所述外壳具有包含核燃料销的中心部分和形成所述组件头部的上部，所述上部包含包括中子吸收剂的上中子屏蔽(UNS)装置和用于可逆地锁定所述外壳的装置和形成UNS头部的可移动重物，所述重物被配置为能够在给定的过程中相对于UNS的其余部分平移移动，所述锁定装置被构造成使得UNS和