Complex or delicate components problem-free post-processing

Anyone who wants to finish complex or delicate components and thereby achieve a certain level of precision in finishing, may come away from a dead end with regular rotary vibrators. Rösler, a specialist in the field of surface finishing using sliding grinding and blasting technology also has a solution for these components in its portfolio.

In most rotary vibrators, an unbalance motor creates a spiral motion of the mass (chips and parts) that allows different types of products to be reworked. "For conventional turning and milling operations, this is an excellent solution. However, there are also workpieces that require a very high degree of finishing such as components that find their application in the medical sector, among others. Even the smallest scratch can lead to rejection. What is important with these types of parts is that they do not touch each other during machining," says Vincent Raman at Rösler Benelux. "Other components such as 3D printed workpieces are so complex that it is almost impossible to fit them in a conventional rotary vibrator."

Complex geometries

For these components, Rösler has a DL series of rotary vibrators in its product range. This type has no central doom around which the media and parts rotate. "The parts are clamped securely in the machine. These can be large parts up to 1,500 mm in diameter or multiple, smaller workpieces in a frame. Once the parts are clamped, the machining media flows around the clamped workpieces. This means that even complex internal geometries can be re-machined, while there are no loose components to touch. This machine type is therefore ideally suited for processing geometrically complex and delicate components. Moreover, the friction ratio is much higher than in a standard vibrator where the parts are machined separately, leading to shorter machining times."

Rims

An example of an application is rims of cars/trucks. "Rims are quite large in terms of size but at the same time, these days, they also often have complex shapes, since the spokes are intertwined. This leads to many angles and edges that are difficult to achieve with regular finishing."

Developed

Round vibrators without central doom are not new. Raman. "The type has been around for about fifteen years now, but it has been constantly developed in recent years. Where previously speeds of up to 1,500 rpm were valid, the new machines reach 3,000 rpm. This leads to faster machining times and successful results, even with more complex parts."

Growing market demand

Market demand has grown in recent years. Raman. "Whereas when the market was introduced, 1 in 100 parts were reworked with this machine, it is now 1 in 2. This is because the market is evolving: customers are becoming more demanding and parts are becoming more complex, also thanks to 3D printing. In addition, it is much harder to find good workers who have the polishing skills. This trend started early on, but is really happening now as most manual polishing companies have stopped due to retirement age of employees."

Additive Manufacturing

Rösler is capitalizing on the 3D printing trend. "The DL AM in our product range is ideal for finishing 3D printed parts made of plastic or metal. An operator mounts the workpieces individually on fixture points. Once he places the frame in the machine, the operator can activate a magnetic field that automatically positions the frame properly in the machine. The media are then automatically added after which the operator can start the operation. Afterwards, the pneumatic media handling system - if this option is chosen - ensures that manual removal of the media is no longer necessary which provides time and cost efficiency. The media is collected in a buffer which allows for reuse. Outside the machine, the operator can already prepare for the next changeover. It leads to time savings as well as the desired high quality."