Turbine shafts are mainly machined through turning and groove-cutting operations with some amounts of drilling. Large amounts of metal are removed and demanding grooves have to be cut.
There is a range of typical turning operations used for turbine shafts that have undergone real continuous improvements. Heavy roughing of large forgings, long, with uneven surfaces but stable conditions are followed by extensive finishing of bearing surfaces. The turning operations performed on power components lend themselves well to improvements through the advances in tool technology.
A check-list of factors that directly affect the level of performance, security and results should include the following. They represent the established set of application parameters that make a lot of difference to the success in turning:
incorporating the latest insert-grade generation, using allround and dedicated grades to optimize individual operations,
best insert geometry for rough turning operations giving even higher levels of metal removal rates,
best Wiper insert technology for even better finish-turning performance and results.
having a choice of good insert-clamping in toolholder to maximizise stability and security,
incorporating the best modular toolholding available for turning operations, for best stability and quick tool changes.
The possibility to apply the best insert shape to maximize strength and to apply the most suitable entering angle is dependant on how extensive a turning tool programme is. The necessary cutting edge also has to be available in the right insert form and size to both optimize the operation and to provide good tool economy. The choice between round insert and square insert with a specific geometry and nose radius can be decisive in optimizing operations – in both rough and finish turning operations.