Process for producing a guide tube of nuclear reactor fuel assembly mandrel for forming the guide tube and the guide tube obtained

摘要

Successive axially spaced sections of a tubular blank (22) are pressed against different axially spaced sections (18,19) and (20,21) of a mandrel (14), which is shifted axially between pressing steps, to produce a tube of uniform external diameter but whose wall thickness varies axially. Also claimed is mandrel (14) which is rotationally symmetrical and whose external diameter varies axially from section (16) to section (21). Also claimed is a guide tube for a nuclear fuel assembly and presenting axially spaced sections with different wall thicknesses but uniform external diameter connected by a section of progressively varying wall thickness longer than 100 mm.