Overcome Jet Turbine Disc Milling ChallengesSpecialized tooling designed around overcoming the unique challenges and strict tolerance needs when manufacturing jet turbine discs and associated components.
Failure is not an option when it comes to turbine blade discs used in both the hot and cold sections of aircraft jet engines. Although the machining of these components requires perfection in tolerances and surface finishes, you also must contend with short turnaround times, constantly changing designs and challenging new materials, as engine and aircraft OEMs strive to reduce fuel consumption as well as CO2 emissions.
To overcome all these obstacles and maintain your profitability, you must optimize each and every operation involved with turbine blade disc machining – including pre-milling, dovetail broaching, splining, edge profiling, and both rough and finish turning. Such complete process optimization is achieved only when you partner with a tooling supplier, such as Seco, that leverages extensive aerospace application experience to provide tooling and machining strategies developed specifically for turbine blade disc machining.
For turbine blade disc pre-milling, advanced Seco high-performance and solid general machining cutters, along with special profile cutters for dovetails and fir trees, enable you to balance time, cost and risk. The tools provide high material-removal rates to shorten cycle times without imparting stress on turbine blade disc base material. While doing so, they also reduce the risk of tool breakage, part damage and scrap.
Aerospace OEMs often have pre-determined turbine blade disc machining operations that you must use, one of which is the broaching of turbine blade disc dovetail slots. In these instances, Seco high-quality tailor-made tools and inserts, such as single-tooth broaching bars, along with advanced CNC programming strategies allow you to achieve extremely tight tolerances and stringent surface finishes much faster in less overall processing time.
Turbine blade disc gear splines typically produced on specialized machines through multiple processes are generated more efficiently and accurately on CNC mill-turn machining centers. This strategy, along with Seco gear skiving tools engineered for use on those multi-tasking machines, eliminates the need for specialty machines and time-consuming setups for processing flexibility and problem-free turbine blade disc spline production.
Besides significantly adding time to machining operations, manual disc deburring increases the risk of operator injuries and mistakes. Seco deburring tools ensure complete access to all turbine blade disc features so you can perform the task as a reliable and consistent CNC-controlled operation on a machine tool.
Rough and finish turning of turbine blade discs are critical operations. Any errors in tolerance or surface finish at this point can result in added processing time or, worse yet, scrapping a very expensive part. To prevent this from happening, Seco ceramic, PCBN and carbide inserts featuring advanced geometries, together with the application of high-pressure coolant, optimize chip control for fewer machining interruptions, longer tool life and higher process security. These advantages enable you to hold tolerances and generate perfect part surface finishes without the use of complex machining and production strategies.
The key machining operations involved in producing aerospace jet engine turbine blade discs include pre-milling dovetails and fir trees, broaching dovetail slots, gear skiving splines, edge profiling, rough turning and finish turning. All operations require holding extremely tight tolerances and generating specified surface finishes while avoiding heat generation that can effect base material integrity. As these sequential machining operations progress, the investment of time and effort significantly increases part value, so anytime you can improve the speed and efficiency of each operation, you shorten delivery time and boost profitability.
Turbine blade discs can require between 45 and 135 dovetails/fir trees with machining time dependent on disc thickness. The female profiles of disc dovetails and fir trees match the male profiles of turbine , compressor and fan blades. In pre-milling discs, advanced Seco high-performance and solid-carbide general machining cutters, along with special-profile cutters for dovetails and fir trees, enable you to balance time, cost and risk. The tools provide high-material removal rates to shorten cycle times without imparting stress on disc base material. While doing so, they also reduce the risk of tool breakage, part damage and scrap. For added cost savings and longer working life, Seco offers reconditioning and recycling programs for dovetail tooling.
Although several aerospace manufacturers have switched to milling disc dovetail slots, many are locked into roughing and semi-finishing them with the broaching method. In these instances, the combination of high-quality tailor made tools and inserts, such as single-tooth broaching bars, along with advanced broaching CNC programming strategies from Seco, enable you to achieve extremely tight tolerances and stringent surface finishes much faster in less overall processing time.
To generate turbine blade disc gear splines, aerospace manufacturers either use dedicated gear machines or opt for gear skiving on multi-tasking mill-turn machining centers. When splining on dedicated gear machines, Seco gear-milling solutions can shorten cycle times significantly critical for large-batch production. However, such specialty machines involve higher initial capital investments and the inevitable production bottlenecks of installation. They also add another machine to the overall turbine blade disc manufacturing process, increasing the risk of setup errors while consuming valuable production time.
Gear skiving turbine blade discs on multi-tasking machines with Seco gear skiving tools boosts part processing flexibility and eliminates the time-consuming setups required for multiple machine operations. With fewer setups, you also significantly lower the risk of errors and stacked tolerances.
Any inconsistencies in deburring/edge profiling turbine blade discs can lead to part failure and catastrophic outcomes. Accordingly, you can perform the task as a mechanized CNC-controlled operation with Seco engineered edge profile tooling. Unlike time-consuming, inconsistent manual deburring that is harmful to workers, MEP removes humans from the equation and takes place in an enclosed machine. The part remains clamped after previous operations to maintain reference points, ensure reliability and high quality while maintaining the health and safety of operators.
The investments of equipment and time involved with manual deburring then shift to tooling for existing equipment. With Seco MEP tooling, you gain complete part feature accessibility – from the top, bottom or along varying radii – so no edge is missed.
Depending on workpiece material, aerospace manufacturers use either ceramic or carbide inserts to rough turn discs. In either case, chip flow control is mandatory to maximize productivity. The combination of high-pressure coolant plus properly programmed Seco ceramic and carbide inserts can achieve effective chip management. You thus experience less edge chipping and insert breakage, which minimizes process intervention and maximizes process security.
Any imperfections in the finished surfaces of jet engine turbine blade discs can escalate into dangerous fractures and part failure. When finish turning, you must meet exacting tolerances and produce perfect surface finishes without generating heat or adding exorbitant amounts of time to the overall production process. To overcome these challenges, Seco provides advanced PCBN and carbide tooling engineered for the machining strategies you can use to achieve imperfection-free disc surfaces with high levels of integrity.
As an aerospace manufacturer, you look to your tooling suppliers as partners as well as a source of productive tools. Additional services from Seco further enhance the quality of that relationship and its value to you. Seco services include tool reconditioning for better amortization of costs, consulting expertise that assists in process optimization and a reliable supply of the necessary tools. A tooling supplier must offer a holistic approach to parameters, machines, fixtures and programming to help manufacturers optimize their entire process and gain maximum value.
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