Machining turbine blades

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There are high accuracy requirements in turbine compressor design. Turbocam International wanted to break new ground in machining turbine blades made from high-alloy steels satisfy profile tolerances and surface accuracies. the company supplies well-turbine manufacturers worldwide with flow path components as well as blades.

Previously, it had only been possible to produce turbine blades up to 150 mm in length at surface qualities that no longer met customer expectations.

Hamuel is a German machine manufacturer of material-optimized CNC machining for high-strength steel, cast materials, titanium and Inconel. He quickly realized that these were two companies meeting at eye level. Hamuel’s HSTM 150 S2 machine has a mineral cast machine base, as well as high damping and rigidity for extreme acceleration. It can deal with all types of flow components, turbine blades with extended lengths, and blisks.

Component geometries with dimensions of up to 600 x 300 mm (LxW) can now be realized and blade profiles can be adapted to manufacturer wishes. Accuracies of 25 µm are achieved with titanium as well as components made from high-alloy, difficult-to-machine nickel-based steels.

Apart from the low-vibration design, the 2nd support axis is key to obtaining surface accuracy. It keeps the component in position and maintains stable clamping even with blades up to 600 mm in length.


In addition to single-blade machining, blisk machining is possible with those machines. This type of manufacturing allows for a closer spacing of the blades, since during the manufacturing process the blade profiles are milled from a forged disc. The latter is attached to the A-axis by a clamping device and can be rotated during machining. The milling head performs the necessary swiveling movements. With these systems, there are hardly any limits to flexibility in production.

Turbocam uses these machines as they provide a balance between the milling process and production processes such as grinding and polishing. The better the surface quality after milling, the less postprocessing is required.