Achieve Cutting Perfection at Every Trochoidal Turn

By: Don Halas, Product Manager, Threading and Grooving API at Seco Tools

When machining costly components, such as those for steam and gas-turbines, process security is vital, in particular when it comes to grooving. The operation is one of the most challenging when machining these components because many of their features limit accessibility, while being made from heat-resistant super alloys and stainless materials often results in high and irregular cutting forces, vibration, poor chip control and residual stresses within the components.

But there is a way to overcome these challenges. The solution is multi-directional turning (MDT) and grooving along with a trochoidal turning technique. MDT allows you to turn a workpiece in both directions when grooving and profiling – providing approach options for working around odd part features, while trochoidal turning is basically the same as its milling counterpart but done in a grooving operation. This is an area where Seco excels, and our comprehensive metal cutting solutions have perfected the trochoidal turning process, making it a more productive and profitable metal cutting solution.

The trochoidal turning technique prevents chip jamming, vibration and residual stress for overall improved process security. During the operation, radial depths of cut are reduced to 15% of the insert diameter, so chip thickness is significantly less and feed rates are higher.

In trochoidal milling, the cutting tool creates a slot wider than its cutting diameter using a series of circular cuts, or a trochoidal tool path. The technique ensures that an optimal chip load is maintained, producing ideal chip widths and thicknesses,

Trochoidal turning is best performed with round or conical inserts, and Seco provides a major advantage over other tools performing trochoidal turning maneuvers because our unique Secolocä clamping method combines a V-shaped top clamp with serrated contact surfaces between the underside of the insert and the toolholder. Our MDT line is universally suitable for a variety of applications including grooving, profiling, turning, parting-off and threading.

When a customer is cutting a costly component, such as a jet engine part, they want to feel secure that their holding insert will not be separated from the holder pocket. Our full round insert is designed for the high temperature super alloys that would quickly wear other inserts during turning operations. Such a strong and stable tooling system helps shops reap the trochoidal machining benefits of reduced cutting pressure, better chip control and longer tool life. Plus, the process makes it possible to produce extremely small, complex, tight-toleranced and thin-walled precision components out of the difficult-to-machine materials used in the aerospace and power generation industries.