HEIDENHAIN at Moulding Expo 2019: powerful TNC functions for perfect forms

Dimensional precision, contour accuracy, and perfect surface quality are typical challenges faced by tool and mold manufacturers, but they are also the strengths of TNC controls from HEIDENHAIN. TNC controls offer numerous functions that bring out the best of a machine in any machining scenario while meeting workpiece accuracy requirements with efficiency.

Tool and mold manufacturers live in the difficult tension between machining requirements and economic demands. On the one hand, dimensional and contour errors need to be so low as to be barely measurable and must certainly never be visible. On the other hand, production processes are increasingly dictated by the need for higher productivity and lower costs.

With live demonstrations and four topic islands at Moulding Expo, the gathering place for tool and mold manufacturers, HEIDENHAIN will be introducing solutions that answer the core questions of a highly accurate and efficient machining setup:

• How can I optimally tune my machine to the given machining conditions? • How can I take full advantage of a milling machine's dynamics? • How can I implement the accuracy requirements of a workpiece efficiently? • How can I plan and monitor automated production with ease?

Poor data quality in NC programs often leads to reduced surface quality on milled workpieces. The Advanced Dynamic Precision (ADP) function enables optimized motion control for feed axes in three- and five-axis milling. Thanks to this function, clean surfaces can be milled in short machining times for contours with highly irregular point distributions in neighboring tool paths. By dynamically calculating the contour in advance, the control is able to adapt the axis speeds to contour transitions using acceleration-limited and jerk-smoothing motion control. The strengths of ADP are apparent, for example, in the resulting symmetrical feed behavior on forward and reverse paths during bidirectional finish milling and in the form of particularly smooth feed-rate curves on parallel milling paths.

Cycle 32 TOLERANCE adapts the machine tool to a specific machining operation. This is important because every machining step performed on a workpiece actually requires its own particular set of machine adjustments. For example, the fine-tuning of a machine for finishing operations emphasizes contour fidelity and contour smoothing but will not permit the same dynamics that a roughing setup can handle. This is where Cycle 32 comes into play: it enables the optimal mixture of accuracy and dynamics, especially in the machining of free-form surfaces requiring extended machining times.

The Dynamic Precision package of functions for the TNC controls eliminates the seeming contradiction between accuracy requirements on the one hand and time and cost pressures on the other. The functions AVD, CTC, LAC, MAC, and PAC reduce the dynamic errors of feed axes in machine tools and significantly improve the contouring accuracy, even at high feed rates and on complex contour paths. In particular, a combination of the CTC function for the compensation of dynamic position errors and the AVD function for active vibration damping helps reconcile the contradictory requirements of accuracy and speed. In practice, this functionality provides greater efficiency during the milling of high-quality, free-form contours. The LAC function, which adapts the controller parameters in accordance with the load, improves the dynamic accuracy of the axis for any load scenario. Jerk values that have been optimized with LAC can thus be used for workpiece feed axes. Since this causes the feed axes to arrive at their target positions more rapidly, machining times are reduced.

3D-ToolComp is yet a further aid in tackling both machining and economic requirements. This option improves accuracy through three-dimensional tool radius compensation, which adjusts for imperfect tool circularity. What’s more, with 3D-ToolComp, the 3-D calibration of a touch probe can be so exact that even free-form surfaces can be measured at the required level of accuracy.

Batch Process Manager intelligently and predictively organizes pending jobs. To accomplish this, the user creates a lineup of jobs directly on the HEIDENHAIN control. These might be jobs for the approaching night shift, for an entire day, or for the upcoming weekend. Batch Process Manager checks this job list and provides important information prior to machining, such as when manual interventions will be necessary and how long the machine will be utilized. Batch Process Manager thereby allows for precise planning of the machining sequence (especially important for unmanned shifts) and facilitates the smooth execution of pending jobs.

The StateMonitor software gives the user a fast, real-time overview of the current machine and job statuses for all connected machines. This monitoring software enables machine data acquisition (MDA) and provides information about machine messages. The user thereby maintains an overview of his machine tools and jobs at all times. With StateMonitor, the user can access any device featuring an up-to-date web browser, including not only PCs, smartphones, and tablets but also, of course, controls from HEIDENHAIN and the add-on work areas of Extended Workspace.

HEIDENHAIN at Moulding Expo: Hall 3, Booth 3D11