The mainframe is the central component of the generator nacelle on a wind turbine and weighs up to 70 tons. Flange-mounted on the mainframe are the gearbox, the rotor bearing and the yaw bearing for connection to the tower. The generator frame holds the generator for producing electricity. Mainframes are subjected to permanent and high dynamic loads. Their manufacture must meet the most rigorous quality and safety requirements. Our precise tools for drilling and milling meet those requirements.
1. Walter Titex drill Alpha® 4 XD: Machining the vent holes
Deep hole drilling up to 70 x Dc without pecking with outstanding XD technology. The K30F cutting tool material makes the XD drills extremely tough so that they are ideally suited to machining steels, cast iron, non-ferrous metals and titanium alloys. These tools have a special flute geometry and the TFP coating for achieving higher performance than comparable tools. The patent-pending XD technology from Walter Titex impresses by delivering six times greater productivity than single-lip gun drills and HSS tools.
2. Walter porcupine cutter F4238: Roughing the main bore
The special design of the Xtra·tec® porcupine cutter F4238 offers outstanding cutting data and high machining performance in spot facing and milling tasks when used in conjunction with the new Tiger·tec® Silver cutting material WSP45S. This combination also guarantees excellent process reliability and features extremely soft-cutting tool geometries.
3. Walter side and face mill: Roughing the bearing surfaces and rear faces
Roughing and circular interpolation without compromise, even under the harshest conditions, with the Walter side and face mill. Maximum tooth quantity and optimum chip clearance ensure maximum cutting performance.
In general, the higher the tower, the greater the turbine’s energy yield because wind speed increases with each metre in height. Sitting atop the tower of a wind turbine are the nacelle and the rotor, resulting in an enormous weight that must also be put into motion. The pod and its adjustable rotor blades are brought into optimum position by the robust pod bearing. The requirements for precision and stability are accordingly high. With our tools, such as the Walter double turning toolholder, the Walter Xtra-tec® side and face mill and the Walter Xtra-tec® Point drill, we offer the user the right tools for machining this weighty component.
1. Walter double turning toolholder: Machining the inner and outer contour
This compact, highly versatile double turning toolholder enables a variety of roughing operations to be carried out using, for example, different approach angels without the need for a tool change. Tool costs are therefore considerably reduced.
2. Walter Xtra-tec® Point drill with chamfer: Machining the connecting bores
The Xtra-tec® Point drill with indexable insert and 45° chamfering insert can drill and chamfer in one operation. The new precision geometry achieves excellent surface quality and precise cylindrical holes. Very tight, hole tolerances (H8) are possible thanks to precision self centring and advanced land technology. The colour of the indexable insert (Walter Color Select) indicates the ISO field of application.
3. Walter Xtra-tec® side and face mill: Milling the stress relief grooves
The Xtra-tec® side and face mills stand out for their high metal removal rates thanks to their positive, soft cutting action. The four-edged tangential indexable inserts reduce cutting material costs and increase process reliability.
In a wind turbine generator system, the rotor hub, made of GGG ductile cast iron, forms the interface between the rotor and the drivetrain, Bolted onto the rotor hub are the blade bearings of the enormous rotor blades. While the rotor hub is part of the rotor, functionally, it is closely associated with mechanical drivetrain. All physical loads, rotor forces and torques are concentrated to a point in this central component. An absolutely stable machining process is indispensable when producing a faultlessly functioning rotor hub.
1. Walter Xtra-tec® Insert drill special tool: Machining the connecting bores
Because of its low cutting forces, the Xtra-tec® Insert drill ensures high process reliability and good chip removal. The wiper edge inserts at the periphery provide outstanding surface qualities. Available as a special tool within four weeks.
2. Walter Prototyp Paradur® ECO Plus: Tapping blind hole threads
The high-performance taps of the ECO product line from Walter Prototyp are all about increasing process reliability where deep blind holes are concerned. The proven THL hard material coating with a new type of surface treatment supports high cutting speeds and promotes a prolonged tool life, enabling a significant reduction in production costs to be achieved.
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.