Manufacture of an air inlet lip or ring sector of an air inlet lip incorporating openings with turned-in edges

A method for manufacturing a stationary air intake lip or a stationary air intake lip annular sector preform, the method comprising:

• arranging a blank facing a three-dimensional forming surface of a die of a hydroforming tool, the three-dimensional forming surface comprising an outer annular portion for forming a one-piece outer wall of the air intake lip or the air intake lip annular sector preform, the outer annular portion comprising at least one cavity protruding through the three-dimensional forming surface,
• forming the air intake lip or the air intake lip annular sector preform by hydroforming the blank on the three-dimensional forming surface of the die, the air intake lip or the air intake lip annular sector preform having a U-shaped section, the one-piece outer wall of the air intake lip or the air intake lip annular sector preform comprising at least one hollow housing with an inturned edge and a bottom, the inturned edge integrally formed with the outer wall and extending both radially and circumferentially inside the outer wall, and
• cutting an opening in a predetermined section of the bottom of the at least one hollow housing while keeping at least the inturned edge so as to obtain the air intake lip or the air intake lip annular sector preform.