Nuclear reactor guide grating for fuel elements - comprising two flat plates with welded vertical strips defining lattice between them

摘要

A guide grating for rod-type fuel elements and control rods in a nuclear reactor comprises a pair of upper and lower flat plates extending over the area of the channels in the core and having rectangular openings corresp. to the channel lattice; a box type construction between these plates being formed by on-edge metal strips welded to the plates between the openings. Each strip extends only over the distance of a few openings (e.g. =3) and at every node point >=1 strip stops, so that there are no cruciform welds between strips. Vertical lengths of tube are pref. welded into aligned holes around the perimeter region of the two plates to act as spacers and join the plates together. Minimal weld distortion occurs.