EJOCLEAN® - Technically clean fasteners from EJOT

Reinraum im EJOCLEAN® Zentrum - Um eine Rückverschmutzung durch luftgetragene Partikel zu vermeiden, wird die Ware im Reinraum verpackt. / Clean room in the EJOCLEAN® Centre - the goods are packed in a clean room in order to prevent re-contamination through air-borne particles.

In der Reinigungsanlage wird die Ware auf das erforderliche Sauberkeitsniveau feinstgereinigt. / In the cleaning plant, the goods are cleaned to the required cleanliness level.

Vakuumverpackte Schrauben im KLT durch Luftpolsterfolie gegen Erschütterungen beim Transport gesichert. / Vacuum packed screws in a small load carrier protected against shocks during transport by air bubble film.

Technical cleanliness as defined by VDA 19 has established itself as a quality-assuring feature in the automotive sector in recent years. The progressively complex electronic and hydraulic components are becoming increasingly susceptible to particle contaminations. Hence, even a single, electrically-conductive particle in an electronic component can lead to total failure. One particular risk in this respect is particle contamination of driver assistance and safety systems in the vehicle.

Since function-critical vehicle components are having to fulfil cleanliness specifications with increasing regularity, project planning departments have been focussing on the concept of "technical cleanliness" for some time now. And fasteners are no exception. Even just a few years ago, it would hardly have been conceivable for screws to be subjected to a complex cleaning process, because the cleaning of screws, as cold-formed, galvanically-coated bulk material, presents a very specific challenge. This area has seen a significant increase in investments in the latest cleaning technologies and packaging concepts in recent years.

Because small parts such as screws are cleaned in high numbers per cleaning unit, it becomes necessary to remove the smallest particles from inside a cleaning basket, so that they can be extracted and then transported through the cleaning agent in use. After this process, a re-contamination in the downstream process steps, such as packaging and transport, has to be reliably prevented. The relative movement of the screws to one another and the associated re-contamination due to surface abrasion, but also the settling of air-borne particles onto the goods pose the greatest risks.

EJOCLEAN® concept

From innovative cleaning technologies, to investments into the latest clean room technology to innovative solutions in the field of packaging concepts and coating systems - the fastener manufacturer EJOT has developed comprehensive know-how in this market segment under the brand name EJOCLEAN®. For example, the development of a packaging concept that preserves the clean state of the screws after ultra-fine cleaning. Immediately after cleaning, the parts are apportioned by specifically trained employees in a clean room, and packaged into ESD (Electro Static Discharge) vacuum bags. The relative movement of the parts during transport has been effectively eliminated by evacuating the air from the packaging bag.

Re-contamination through surface abrasion during on-going internal transport or on the way to the customer is thereby prevented. Moreover, the ESD packaging material can prevent the packaging itself, for example, from becoming a magnet for air-borne dirt due to electrostatic charging.

Especially suited for direct fastening into metal

EJOT has also taken an innovative approach for the cleaning of waxed screws for direct fastening into metal. As a rule, self-tapping screws made of metal, ALtracs® Plus screws for instance, are used with torque reducing waxes. However, this type of coating does not have sufficient stability to withstand a cleaning process. As a result, the ultra-fine cleaning process impacts the fastening properties. That's why applying such waxes only after cleaning has been state of the art until now. However, the clean state of the parts immediately after cleaning could not be maintained. This was due to an almost inevitable enrichment of residual dirt particles in the wax baths, and also because the final wax coating is another step during which the parts can become contaminated. EJOT therefore developed "EJOSEAL 4C", a wax which permits the use of a final cleaning process after the wax coating.

To keep abreast of the continuous further development of manufacturing processes in the automotive sector, the cleanliness of function-critical vehicle components will have to meet even higher standards in the future. "Technical cleanliness" is also gaining importance in technologies outside the automotive industry, since connection technology contractors will soon have to satisfy tougher cleanliness requirements.