Eliminating surprises with simulation: General Industry Coverage

Courtesy of All images: CGTech

CGTech’s VERICUT software performs 3-D simulation of an impeller being cut on a Mori Seiki NMV 5000 5-axis vertical machining center.

As machine tool and part design complexity grows, part program verification using CNC machine simulation software has become an essential tool for ensuring NC programs machine the part correctly the first time. Skipping the verification step risks costly production delays where the machine tool waits while NC program errors are corrected.

VERICUT is a software program that interactively simulates and displays the material-removal process of an NC program. NC programmers use the software to verify the quality and accuracy of their NC programs while VERICUT’s 3-D machine simulation checks for collisions. But the goal of simulation is not simply a collision-free and efficient NC program. The first and most important goal is verifying that a program produces the correct workpiece.

The simulation software’s in-process model tells a programmer whether or not his program makes a correct part. For example, many NC programs incorporate circular interpolation. VERICUT emulates the circular motion and creates an as-machined cylindrical feature that can be measured to ensure its correctness. This is in contrast to internal simulations that do not emulate circular motion, but instead divide that motion into a series of linear motions approximating the cylinder. These segments are not measurable as a cylinder.

The software’s development is driven by evolutionary changes in manufacturing technology, including CAD/CAM software features, machines and tooling, machining techniques and processes, as well as the need by manufacturers to implement and improve on these changes. The following trends and challenges produced ongoing manufacturing software enhancements.

More manufacturers need to simulate specialized machining processes and complex machines. When a specialized process reduces cycle time or increases reliability, more companies adopt it. By simulating these “special” processes early, VERICUT supports the next customers to adopt them. For example, years ago it was rare to see an NC program utilizing now-common local part coordinate transformations and tool-axis vector programming. VERICUT supported these features when they were initially adopted, and others have benefited since.