Abstract: The installation comprises a bath storage reservoir (4), a treatment tank (6) to receive the component that is to be treated which is carried by a support tool (10) collaborating with the tank, respective pipes (5, 7) for conveying the bath from the reservoir to the tank and for emptying the bath from the tank to the reservoir, and motion instigating means (8) for setting the bath in motion in the closed circuit. Advantageously, the tank (6) is of elongate shape with a longitudinal axis and a cross section that is substantially constant between the respectively upstream (12) and downstream (14) opposite transverse ends of the tank, said bath conveying (5) and emptying (7) pipes are respectively connected to the upstream and downstream ends of the elongate tank along the longitudinal axis thereof and the tooling (10) carrying the component (P) that is to be treated, which component is placed in the tank (6), is mounted fixedly thereon.