Rotamat: Volumetric flow rate control of the coating material increases process stability

Coating of mass produced small parts

Rotamat: Volumetric flow rate control of the coating material increases process stability

The new Rotamat coater with automatic control of the volumetric flow of the coating material.

At the PaintExpo 2022 Walther Trowal introduces the new Rotamat R 85 equipped with the new volumetric flow rate control of the coating material. This increases the overall stability of the coating process for mass produced small parts, ensures absolute repeatability of the paint application and simplifies the equipment operation.

Over many years the Rotamat coaters from Walther Trowal have proven to produce excellent coating finishes on mass produced small parts made from elastomers, metal or wood. Effective immediately the Rotamat R 85 will be equipped with a volumetric flow rate sensor for the respective coating material: It provides precise measurements in real time for the exact control of the volumetric coating material flow rate down to a tenth of a gram per minute.

To date the pressure in the inlet air piping to the spray nozzle(s) was the control variable. In the new Rotamat R 85 coater the flow rate of the coating material has become the main control parameter: Depending on the measurements of the new sensor the pressure is adjusted to a value that maintains a constant volumetric flow rate of the coating material. This guarantees that the coating operation always takes place with the predefined material quantity and ensures that the desired coating thickness can be precisely and reliably maintained throughout the entire process.

The actual volumetric flow rate is displayed on the newly configured touch panel, and any deviations are immediately indicated. Another benefit of the new control system is that it allows maintaining the exact duration of the preset cycle time for the coating operation.

Frank Siegel, sales manager “coating technology” at Walther Trowal, predicts that with the new flow rate control system the customers will gain significant advantages: “The employees at a pilot customer reported that with the new control system they can quickly recognize any process faults and can immediately take corrective action. For example, they can quickly clean clogged spray nozzles without having to interrupt the coating process for a long time.”

Background information

Rotamat coaters are highly cost-efficient systems for coating mass produced small parts like O-rings, handles, springs or screws. They can be used for coating a wide range of components made from metal, wood, rubber or different kinds of plastic.

This includes parts for the automobile and cosmetics industry, components for writing utensils, games, clothing accessories as well as sealing and dampening elements. Rotamat coaters are equally suitable for the application of water or solvent based coating materials

Rotamat systems are equipped with a rotary, closed drum. The drum rotation causes the work pieces to gently tumble over each other, while an automatic spraying system is applying the coating material. The injection of hot air ensures that the coated parts are immediately dried. This results in an extremely homogeneous surface coating with an absolute precise coating thickness and a high life expectation of the applied coating material.

Even delicate parts with complex shapes are leaving the machine with a homogeneous coating, completely dry and without sticking to each other. They can be immediately utilized for further downstream manufacturing operations.

The coating process runs fully automatically. All the operator has to do, is placing the raw work pieces into the drum and removing the coated products. Compared to conventional coating systems the time-consuming and costly placement of the work pieces on racks is completely eliminated.

Rotamat systems are not only suitable for the application of decorative coatings with a wide range of water and solvent based decorative and functional lacquers. But they can also be utilized for applying lubricant materials, bonding agents, corrosion protection lacquers or insulating coating materials.

Walther Trowal at the PaintExpo 2022

April 26 – 29, 2022 in Karlsruhe/Germany

Hall 2, booth 2310

About Walther Trowal

Surface finishing technologies from the inventor of the “Trowalizing” process

Since 1931 Walther Trowal has been developing and producing systems for the refinement of surfaces. Initially focusing exclusively on mass finishing – the term “Trowalizing” derived from the company”s cable address “Trommel Walther -Walther Trowal has continuously expanded its product portfolio.

Over time the company has developed a broad range of machinery and systems for mass finishing, shot blasting and coating of mass produced small components.

With the invention of new systems like, for example, drag finishing and the development of special finishing methods for 3D printed components the company has proven its innovative capabilities again and again.

Walther Trowal develops and implements complete surface treatment solutions that can be seamlessly integrated into the linked production systems existing at the customers. This includes the entire process technology, perfectly adapted to the specific surface finishing requirements of the work pieces: Equipment and the respective consumables always complement each other in a perfect manner.

Each individual work piece and each manufacturing process must meet special technical requirements. That is why the experienced process engineers in our test lab, in close cooperation with the customers, develop the optimal process technology for the finishing task at hand. The result: Work piece surfaces that meet exactly the required specifications…with short processing times and a high degree of consistent, repeatable results.

Walther Trowal is one of the few manufacturers who develops and produces all machines and mass finishing consumables in-house… including ceramic and plastic grinding and polishing media as well as compounds.

The company”s equipment range also includes all kinds of peripheral equipment for handling the work pieces like lift and tip loaders, conveyor belts and roller conveyors, in addition, special driers for mass finishing applications and, last-but-not-least, systems for cleaning and recycling of the process water.

With its exchange program for wear items like work bowls, which are part of a continuous recycling program, Walther Trowal conserves valuable resources and, thus, makes a significant contribution towards sustainability in the field of industrial production. Quick technical support and the global repair and maintenance service ensure high uptimes for our equipment.

Walther Trowal serves customers in a wide range of different industries all over the world, for example, automotive, aerospace, medical engineering and wind power.

Walther Trowal GmbH & Co.KG
Georg Harnau
Rheinische Str. 35-37
42781 Haan, Germany
+49 2129 571-0
+49 2129 571-225

VIP Kommunikation
Regina Reinhardt
Dennewartstraße 25-27
52068 Aachen, Germany
+49 241 89468-24