01. Walter WIS10 ceramic grade for roughing the linear dimensions and the outer diameters.
02. Walter Tiger•Tec® Silver PVD WSM23S grade for machining the cut-ins.
03. Walter Tiger·Tec® WSM20 grade for finishing the linear dimensions and the outer diameters.
04. Walter Xtra·tec® Insert Drill B4212 for solid drilling of the core hole.
05. Walter Tiger·Tec® Silver PVD WSM23S grade for machining the pocket centre.
06. Walter Tiger·Tec® WSM30 grade for machining the pocket.
07. Walter NTS for cutting the internal thread.
08. Walter Prototyp ProtomaxTM Inox for opening the slots.
09. Walter Prototyp special form cutters for machining the onion profile.
Gas and Steam Turbine Housing
Those who want to operate gas turbines cost-effectively for power generation need turbines that withstand high pressure and temperatures. The components used for this purpose are exposed to extreme thermal and mechanical loads. Temperatures as high as 1500 degrees Celsius in the combustion chamber can only be mastered with extremely robust materials, mostly stainless or super alloys. With steam or condensing turbines, there are also enormous physical forces acting on the components, e.g. 1.5 times the speed of sound at the tip of a turbine blade. Here, only highly durable martensitic steels or titanium alloys are used as materials. We have the right metal cutting tools for machining these extremely demanding materials, and we use them to develop the appropriate machining processes.
1. Walter back counterbore: machining the seating face and clearance diameter for securing mechanism
With this high-tech draw bar tool from the technology brand MODCO®, back counterboring is possible even under unfavourable conditions. The automatically controlled cutting edges in Z = 2 design are actuated using coolant or compressed-air.
2. Walter Steam-tight mill: Fine-finishing the interfaces
A precision tool for fine-finishing the interfaces in steam turbine housings. Surface qualities of Ra 0.25 to 1.6 are achieved with a planarity from 0.01 to 0.05, over a length of 1000 mm. Available in 80 to 400 mm diameter with a wiper indexable insert (wiper geometry) mounted in a cartridge.
3. Walter heavy-duty cutter F2265: Roughing the interfaces
The Walter heavy-duty cutter F2265 is the ideal roughing tool when it’s time to get down to business. This mighty cutting tool has large, open chip clearances for optimum chip removal and offers excellent cutting data combined with high cutting performance.
4. Walter PrecisionMAXI B3234 precision boring tool: Finishing the burner holes
A powerful, modular precision boring tool in a bridge design with cartridges (Ø 150-640 mm). The indexable inserts have three cutting edges and are available in all required sizes. The tool with Capto™ or NCT interface can be adjusted with fine precision (0.01 mm Vernier scale) and has internal coolant supply directly to the cutting edge.
01. Walter Tiger·Tec® WSM20 grade for roughing the linear dimensions and the outer diameters.
02. Walter Tiger·Tec® WSM20 grade for finishing the linear dimensions and the outer diameters.
03. Walter Xtra·tec® high performance cutter F4030 for opening the airfoils.
04. Walter ball nose cutter F2139 for finishing the airfoils.
05. Walter Prototyp ConeFitTM Protostar N40 ball nose cutter for machining the transition radius.
06. Walter Xtra·tec® Insert Drill B4213 for core hole drilling of the mounting hole.
A turbine blade at full load covers up to 500 metres per second. This corresponds to a centripetal acceleration of 160,000 m/s2 with centrifugal forces of around 550 tonnes. The machining of complex blade profiles made of difficult- to-cut materials is a real challenge. The goal is faultless components that are in line with market requirements. We achieve this with a precisely matched range of tools for roughing and finishing. The compressor blades and vanes are also exposed to the highest of thermal and physical loads. The difficult cutting properties of the materials, such as Inconel, are an additional problem alongside the complex blade profiles. With our special machining solutions for these tasks, our users reduce the in cut times to an absolute minimum whilst achieving the best possible dimensional accuracy of the components at the same time.
1. Walter BLAXX F5041 shoulder mill: Semi-machining the turbine blade
When semi-machining the turbine blade, the powerful Walter BLAXX shoulder mill enables deep cutting depths (up to 9 mm) and high feed rates at the same time. With the tangential indexable inserts with four cutting edges, true HPC when machining turbine blades is possible here. Axial forces and vibrations are practically eliminated through the use of smaller corner radii.
2. Walter Prototyp Protomax™ ST: Finishing the turbine blade
The Protomax™ with self-centring ConeFit™ threads is the best choice for finishing the turbine blades. Conical centring provides the highest concentricity, and the 50° helix angle ensures a soft cutting action and good chip removal. The TAZ coating guarantees high cutting speeds and rapid metal removal rates.