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Machining at Any Angle

Feb. 23, 2012
New sliding/fixed headstock automatic lathe with B-axis

The Traub TNL18 lathe’s pivoting B-axis expands its flexibility for machining complex, highly contoured parts.

The Traub TNL18 sliding/fixed headstock automatic lathe with seven linear axes is available with an extra B-axis, meaning it is applicable to particularly challenging machining tasks. With the additional B-axis in the upper tool carrier, which can pivot 100°, complex parts and complicated contour elements that also require additional operations such as milling, drilling, lateral drilling or l threading may be machined at any angular position by the new TNL18-7B.

Until now, for parallel main spindle operations, angled toolholders were necessary with "normal" turret positioning. Traub’s new turret simply pivots. The 8-position turret with the double-driven toolholder per position capability offers added flexibility. Other benefits include set-up time reduction (no need to set up angle-adjustable toolholders); cost reduction (no need to use angle-adjustable toolholders); higher workpiece quality (absence of angle-adjustable toolholders leads to more stable machining); and complexity gains (a greater variety of workpieces can be produced more flexibly and efficiently in one setup.)

Tool turret indexing is carried out by an NC rotary axis without a mechanical lock. This permits free angle positioning of the turret. All turret stations can be equipped with fixed or live toolholders, and the number of tools in the machine can be increased to as many as 54 tool stations through dual- and multi-toolholders. There is less setup effort for the operator, resulting in more productive time, and the high-precision, fast turret indexing enables a very fast chip-to-chip time of 0.3 seconds (comparable to a linear tool carrier.)

The TNL18-7B is supplied with the new Traub compact shank system, an improved system for high-precision mounting of toolholders in the turret. Toolholders are seated deeper in the turret, which results in less leverage effect and, thus, higher stiffness. For live toolholders, the large shank diameter makes it possible to insert roller bearings with large diameters. A quick-change system permits a high-precision and fast tool change without removing the toolholder. The compact shank system increases tool life and also contributes to improved surface quality.

It takes just a few steps to convert the Traub lathe from sliding headstock to fixed headstock turning mode and vice versa. The extremely long Z-travel distance of the headstock ensures proper positioning of the main spindle, either for sliding headstock turning or fixed headstock turning. The main spindle is equipped with a C-axis as standard and it delivers high torque in order to achieve large cutting volumes.

The vertical machine bed design results not only in a favorable chip flow but also an extremely compact footprint. This is made possible by integrating the control cabinet in the upper part of the machine, enabling space-saving integration of the automatic lathe into existing machine groups or cells.

The working area is easy for the operator to access through a high and wide sliding door, which provides ample room for setup and changeover activities. The inspection window allows the operator to keep a close eye on the machining process. For service, the back cover removes quickly to provide full access to mechanical assemblies. The hydraulic and pneumatic components are arranged with full accessibility to the rear of the machine and are easy to check.

The TNL18-7-B is equipped with the Traub TX8i-s control, which is based on a major control manufacturer’s CNC; the user interface software is dedicated to the Traub system. The control allows shorter setup time due to higher-efficiency NC performance. Alternate programming, optimization, and simulation are available in interactive or NC mode, while error avoidance and setup time reduction are achieved thanks to object-oriented interactive user guidance (integrated TX8i-s.) A tool-break-and-wear monitoring function supports control effectiveness and productivity.

About the Author

Robert Brooks | Content Director

Robert Brooks has been a business-to-business reporter, writer, editor, and columnist for more than 20 years, specializing in the primary metal and basic manufacturing industries.