Together with Paul Horn GmbH, the Kistler Group has developed a solution that allows tools for micro-turning operations to be monitored in real time. The Piezo Tool System, or PTS for short, consists of a piezo force sensor and analysis software. It measures the cutting force and the tool load while the machine is running. The data obtained provides information about the expected service life of the tool or cutting inserts. Defective materials and cutting materials or even tool breakage are detected immediately, which minimizes rejects.

The new solution is particularly suitable for use in turning operations in the micro range. Alternative measuring methods, such as spindle monitoring, do not provide meaningful results due to minimal deviations in the drive power. Even with structure-borne sound measurements, consistent results cannot be achieved with small workpieces. Optical solutions are also ruled out due to the cooling lubricants used and the high rotational speeds during the machining process.

The PTS continuously records cutting forces. The evaluation of this data provides a trend analysis of the tool life of the cutting tool. This makes it possible to better utilize tool life for more efficient production. At the same time, employees no longer have to constantly monitor the machines, meaning that production can run partially unmanned.

"Our tests have shown that, in most cases, only the critical tool in a production process needs to be equipped with PTS," says Gunnar Keitzel, Head of Machining. "Not only is the tool life massively extended, but the workforce can also be deployed more efficiently. A single employee has an overview of all processes and can therefore take care of several machines at the same time."

The PTS from Horn © Horn

The new solution is compatible with Horn's standard turning holders. It does not require any intervention in the CNC control and can therefore be used independently of the machine. The sensors are lightweight and can be replaced quickly. The Piezo Tool System thus leads to lower production costs with increased production capacity.

According to documents from Kistler