BSH Traunreut processes highly sensitive components in the production of its household appliances, some of which are manufactured in clean rooms to minimize the failure rate. A more than 300 m² ISO class 7 Cleanroom was installed in 2021 for up to ten process systems, with plans already in place to expand the area at a later date. The Bavarian company relied on a modular cleanroom system from Schilling Engineering, which offers the option of converting and connecting individual elements.
Expansion of the cleanroom area planned
The decision to use a modular cleanroom system proved to be the right one, as the planned extension of around 100 m² was required after just two years. The cleanroom conversion awarded to Schilling Engineering was to be carried out during ongoing operations with a maximum downtime of one week. One particular requirement was to extend the Cleanroom into a continuous room without partition walls and disruptive supports. As there is no possibility of suspension in the factory hall, the existing Cleanroom was designed to be self-supporting and the 15 m width was bridged with specially constructed 1.20 m high trussed ceiling beams. The clean room extension was constructed in the same way.
Conversion during ongoing operations
The conversion was carried out in two phases. In the first two-week phase, initial preparations were made for the subsequent connection. The material lock, which was located in the connecting wall that was later removed, was dismantled and installed elsewhere, a sliding door was replaced with a roller shutter, and a second dehumidifier and a second control monitor were installed. Thanks to the modularity of the system, this work could be carried out quickly and without interrupting ongoing operations.
In a second six-week phase, the extension was assembled and the electrical preparations made. The room extension was completely installed with an open offset of 1.5 m as a gap. This meant that the 15 m long ceiling beams were delivered to Traunreut prefabricated in one piece at the cleanroom manufacturer’s factory. The approximately 100 m² ceiling of the self-supporting room was made completely accessible on request.
Five working days for final connection and commissioning
Production was interrupted once in a short period of just five working days to carry out the final connection of the two cleanroom systems. During this time, the production machines were packed and a dust protection wall was installed to protect the existing cleanroom area. The service technicians from the cleanroom company now had to work quickly and in a coordinated manner to successfully complete the open 1.5 m connection in the short time available. The plenum was opened and the partition wall to the existing Cleanroom was removed. The ceiling was added, connections adjusted, final fittings of the ducts connected and sealing work carried out. The electrical rewiring posed a particular challenge, as the extension components could only be installed in the space reserves after the shutdown. After further finishing work, the Cleanroom was handed over ready for operation on schedule. Production of the household appliances was able to continue seamlessly. The cleanroom employees at BSH are particularly pleased with the generous glass surfaces with daylight and the very quiet operating state of the ISO 7 cleanroom, where a noise measurement < 60 dB was measured.
