SECTOR: DOMESTIC APPLIANCES APPLICATION : painting PROBLEM: The realization in a washing machine factory with production of a painting plant of shells of different dimensions in different colours in lots of varying quantities. In addition the plant had to permit different pre-treatment processes and at the same time to optimize the production of washing machines with relation to the scheduled assembling program. Specifications : different materials of washing machine shells which means different pre-treatment processes; the need to reduce the time between the painting of the shells and their application on the washing machine assembly line (daily output schedule); the need to reduce the buffers of the various shell models already painted and waiting to be assembled.   SOLUTION : The plant is based on System 2000 P & F overhead conveyors and consists of three lines to carry out the pre-treatment: one for the 8 stage pre-treatment and two of these to effect the 9 stage pre-treatment. The lines are linked with the painting installations by two high-speed recycling loops. The painted items are then addressed and stored in five different buffers in accordance with the washing machine assembly schedule. The adopted control and software enable to combine during loading operations the trolley code to the shell code thus making possible to address the trolleys to the scheduled process, the buffer and the assembly line in which it will be used. The plant control also includes a self-diagnosis system to identify malfunctions and it is furthermore connected to the top level information system.