Precise contours freely programmable

Valve seat machining with the KomTronic®  U-axis system


Machining valve seats in cylinder heads usually requires the use of special tools which have been adapted to specific contours. At HPP High Performance Production GmbH, a KomTronic®  U-axis system is used for this operation. We then not only do not need to acquire angle tools, we're also faster and more flexible”, confirms Managing Director Dipl.-Ing. Frank Melchert.



At HPP, high performance production (which gave them their name) is produced on a first-class assembly of machines in a fully air-conditioned environment. The company, which belongs to the BÖLLINGER GROUP, specialises in the high-quality machining of high-tech engines, gearboxes and vehicle components in an extremely wide range of materials for the automotive and aerospace industries. “Wherever an extremely high level of precision is required, we are able to produce components which are ready for installation,” adds Mr Melchert. More specifically, he explains that this involves state-of-the-art machines and measurement instruments which have been designed to manufacture prototypes or low-volume ranges for niche products using high speed machining equipment. This includes a class 2 measuring room with appropriate measurement instrumentation and a suitable, TÜV certified quality management system.


Just as responsive as with standard tools


Machines, control systems, equipment and tools have been extensively standardised, as is appropriate for the type of operations performed by the high-end manufacturer based in Bad Friedrichshall. In this way, we achieve an extremely high level of flexibility and are able to react quickly to our customers' requirements,” explains the energetic General Manager. However, not all machining requirements can be met with existing or easily available standard tools. Jobs such as machining valve seats in cylinder heads call for special tools which have been adapted to the required contour. These give rise to extra costs and involve relatively long delivery times as well as, ultimately, tool change time considerations for the machine. A KomTronic® U-axis system, however, is freely programmable. It even allows the turning work on the valve seats to be performed in the machining centre in one contour operation. Using the U-axis, HPP is quicker to react and faster in the machining.


Universally deployable in prototype manufacture


When Mr Melchert talks of being more flexible and faster, he does not just mean the machining of cylinder head valve seats. Other components, such as gearbox housings, often require recesses or complex drilling contours to be machined, for which a large number of tools or even special forming tools is necessary. This is where the automatically exchangeable KomTronic® U-axis system creates flexibility, because no tools have to be designed and ordered which are then usually only used for this one particular operation. Therefore, not only cylinder heads but also complex gearbox housings in a wide variety of different types can be fully machined, with short reaction times, and even then in just one clamping operation, without changing the machine.


In summary


At HPP, the KomTronic® U-axis system from the KOMET GROUP  has encountered one of the most demanding fields of application. It satisfies the most demanding of requirements for accuracy as in the case of valve seat machining jobs, and creates exceptional flexibility for prototypes which change from day to day. Likewise in small-volume production, it demonstrates its cost-effectiveness through saving on tools and fast machining times.



The mechatronic  KomTronic® u-axis systems essentially consist of one compact facing head with single slide that is driven by a servo motor and threaded spindle. The power supplied to the electronics and the drive is transmitted contact-free and inductively to the U-axis system. Similarly, the data is exchanged inductively with the U-axis system. A "stator" is mounted on the spindle side. It is segment-shaped, which permits the tools to be replaced automatically. The ring-shaped inductive transmission unit (rotor) on the U-axis side ensures reliable data and energy exchange in every angular position, even when coolant is being used. The mechatronic U-axis systems are therefore automatically exchangeable NC-axes. For flexible contour machining and grooving operations, the U-axis is interposed with the Z-axis. Programming is carried out in the usual NC programming language and is integrated into the machine control system. All the functions of normal ISO programming are available. A customised snap-on tool is used for valve seat machining, which in this case is equipped with a PCD indexable insert from the standard KOMET® range.





Komet-0909-U-Achse_HPP-Bild1a+c: Jobs for which special tools are normally required, such as valve seat machining, are completed by a freely programmable KomTronic® u-axis system in one contour operation.


Komet-0909-U-Achse_HPP-Bild2: A KomTronic® U-axis system is freely programmable and even allows lathe machining on valve seats to be completed in a machining centre in only one contour operation.


Komet-0909-U-Achse_HPP-Bild3: In the picture (right): Frank

Melchert, General Manager, with his colleagues Stefan Kniel (left), Operations Scheduling Manager, and Harald Seyfried (Production Manager)






U Axis
Valve seat
Valve seat