The aim of the present invention is a manufacturing process for assembly parts (101, 102, 111, 112) for the manufacture of elements of chemical devices (100), comprising the fixation of an anticorrosion metallic coating (31, 32) on an unprocessed assembly part (21, 22), by means of an operation comprising a brazing operation under a controlled atmosphere and, possibly, the shaping of the coated part (101, 102), by plastic deformation. The brazing temperature is preferentially less than approximately 750.degree. C., and more preferentially between 600.degree. C. and 720.degree. C. The process according to the invention makes it possible to fix solidly on a steel plate an anticorrosion coating with a thickness less than 1 mm.