Creativity and the art of engineering
A 60-tonne turbine shaft is fully machined in a single operation for a third of what it used to cost.
The job was a serious challenge: A large turbine shaft with a new geometry for use in gas-fired power stations was to be machined in a single operation. The solution demanded a great deal of creativity and all the art of engineering, not only when constructing the machine, but also when designing the machine tool. And to achieve this, two Austrian companies worked hand in hand. Mechanical engineers Weingärtner built the huge machining center. And carbide expert Ceratizit supplied the machining concept including all the key tools.
The close collaboration between the two companies was extremely fruitful. Although the project team had originally set themselves the target of halving the previous machining costs, it became possible to reduce them to a third during the course of the project.
Weingärtner was awarded the contract because they managed to considerably enlarge the existing machining center, which represented a clear competitive advantage. “Up to that point, the maximum weight of the workpiece between headstock and tailstock had been restricted to 30 tonnes. We doubled this to give 60 tonnes, at the same time permitting larger turning diameters of up to two meters,” says Werner Pommer, responsible for technology and sales at Weingärtner.
Ceratizit developed the milling concept for machining the high-strength alloy steel blank. “Our objectives included a high level of shaping precision, process reliability, a long service life and high productivity,” explains Peter Uttenthaler from Ceratizit’s sales team. Another important criterion that influenced the selection of the tool supplier was that availability of all the tools is guaranteed at all times. To achieve this, Ceratizit developed a logistics concept based on three aspects: A rolling forecast of the customer’s tool requirements. Requirements planning for the necessary tools at Ceratizit’s logistics center in Kempten and in Ceratizit’s US subsidiary. And, last but not least, a sharpening service provided by Californian subsidiary Promax Tools.