Some fields of application for our screw fittings and valves are subject to high cleanliness requirements. For many years, SERTO has provided the options US (cleaned with ultrasound and not lubricated), OX ((cleaned with ultrasound, lubricated for use in oxygen systems) and SI (cleaned with ultrasound, lubricated silicon-free for use in combination with paints and lacquers). The components pass through the cleaning system and are assembled and individually packed in the SERTO ISO Class 8 clean room.
To achieve the required high level of cleanliness of surfaces which are in contact with media, SERTO developed a multi-stage process in cooperation with specialists. The components which are to be cleaned are placed in special baskets, adapted to their size. This ensures proper drainage of the cleaning and rinsing media.
In total, the cleaning plant consists of 9 sections, which include an ultrasound cleaning bath with alkali, with acid and with de-ionised water. These are separated by rinsing baths with osmotic water and completed with two drying sections. Over the last sections, a so-called air curtain prevents contamination of the cleaned components by dirt from the air. We continually treat the 600 l of rinsing water in our cleaning plant. Every week we use about 25 kg of regenerating salt. The slight loss of water is continuously topped up with tap water. The material – brass or stainless steel – determines the sequence of the baths which are passed through. The quality is monitored according to ASTM and each cleaning order is documented.
The cleaning and lubrication of NON-SERTO parts is only possible under certain conditions and must be clarified in advance.
To ensure that components are not subsequently contaminated after cleaning, assembly and packaging of the individual components into separate bags is carried out in an air-conditioned clean room directly next to the cleaning plant. The SERTO clean room complies with ISO Class 8, which means that a specified number of particles in the air must not be exceeded. An annual validation by an external testing laboratory guarantees compliance with the prescribed values.
People are the largest source of particles and other contamination. Therefore, suitable work clothes (e.g. hoods, galoshes and a lock for changing clothes), special equipment and tools (e.g. lint-free cleaning cloths) as well as appropriate working methods are prescribed. In addition, our clean room has an excess pressure of 30 Pa so that no dust can enter the room when the door is opened.
The cleaned US components form the basis of our options with special lubricants (OX and SI) and on the other hand are the right solution of customers who use their own lubricants.