Example: Turbine Blade - Siemens SINUMERIK 840D Manual

Driving gear and turbine components
5.2
This example relates to the milling of a turbine blade. The blade is modeled using a CAD/CAM
system.
Turbine blade
Plane roughing
5-axis copy milling,
face finishing
© Siemens AG All rights reserved. SINUMERIK, Manual, 5-axis machining

Example: Turbine blade

At the modeling stage, it is essential to ensure
that the machining strategies take account of
the chucking conditions that will apply during
production.
As a general rule, the contours of turbine
blades are milled in a helical path, i.e. a full
rotation is performed around the Z axis using a
suitable chucking device.
Roughing was carried out by machining the
upper and lower surfaces with the plane
roughing method. This figure shows the tool
paths involved in machining the upper surface.
From the point of view of ensuring optimum
performance and surface quality, constant Z
plane roughing is a highly effective approach
and allows good control over the level of
stress to which the tool is subjected.
The 5-axis copy milling method was used for
finishing purposes, as this allowed face milling
in the form of helical finishing to be performed
in accordance with axis selection. The tool is
set at a lead angle.
5.2
87