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HybridCell for Turbine Blade Hole Drilling

EDM and laser are the two proven technologies for drilling precision holes. Makino and Synova have developed a hybrid cell, combining both technologies to offer the ideal solution for drilling tapered or funnelled holes in turbine engine components.

By Nitin Shankar

The Makino-Synova HybridCell, combining laser and EDM technologies, is changing the way turbine blades are machined. 

This is an example where Synova’s patented Laser MicroJet® (LMJ) laser and Makino’s state-of-the-art EDM hole drilling machine complement each other in machining turbine blades. 

Turbine blades are often the limiting component of gas turbines, subjected to enormous centrifugal forces and high temperatures of around 2,500°F (1,370 °C). These stress levels weaken the blades and make them susceptible to creep failures. To survive in this difficult environment, turbine blades use exotic super-alloys, thermal barrier coatings and internal cooling air channels.

Metallurgical quality is of importance in turbine blades. With dry laser machining, the crucial characteristics pertain to the recast layer (the re-adhered molten material) and to the heat-affected zone (altered microstructure area of the underlying base material). These factors can impact the operating life cycle of the component. With Synova’s patented ‘wet’ laser, these risks are reduced to a minimum.

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