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Efficient coating of O-rings

12 July 2018

Walther Trowal's newly designed Rotamat R 60 for coating mass-produced small parts such as O-rings was developed for users who are increasingly switching to smaller batches and, generally, lower batch volumes. However, the R 60 offers all the features found in its larger 'siblings'.


The Rotamat R 60 allows efficient processing of work piece volumes between 2 and 15L. With a diameter of just 600mm the drum is suitable for small batch volumes. The inclination of the drum is adjustable within a wide angle, allowing adjustment to different work piece geometries. It allows intensive mixing of the parts in the drum and is said to guarantee complete, optimum coverage by the spray nozzles.

With the new machine Walther Trowal takes into account that in connection with just-in-time requirements, many companies often place purchase orders in smaller work piece quantities.

Frank Siegel, sales manager, coating technology at Walther Trowal, says: “Many of our customers want to coat small part batches but do not want to give up the high technical standard we have implemented in our larger units R 80 and R 90C. With the R 60 they can now efficiently coat small batches without having to invest in a larger machine.”

For the Rotamat R 60, Trowal engineers have used the components of the larger machines: For example, the inlet and exhaust air system, the explosion protected LED lighting inside the drum and the mounting of the drum.

Precise control of the inlet air temperature

The measuring point for the inlet air temperature is immediately at the drum entry. Compared to measuring the temperature with a sensor behind the air heating unit the measurement is now much more direct allowing extremely precise temperature readings. 

Eco-friendly operation

For typical applications – today 90% of all customers are using water-based paint – Walther Trowal supplies a specially adapted filtering system. For coating tasks with solvent-based paints the new R 60 – like with the bigger Rotamat units – can be equipped with a four stage exhaust air filtering system with a Papp filter, a filter mat and two pocket filters.

Low energy requirements

The capacity of the heating unit was adapted to the smaller drum diameter, resulting in considerably lower overall energy requirements. Depending on the technical characteristics of the work pieces and/or paint Walther Trowal can equip the machine with PID or pulse control for the heating unit. The result: Customers can also use paint types that do not allow going over or below certain operating temperatures.