Headquartered in Büren (Germany), Heggemann AG is a development and manufacturing partner for major aerospace (and automotive) OEMs; it is also a user of CAM software from Open Mind Technologies (
www.openmind-tech.com). The companyrecently upgraded its CAM software to incorporate the new high-performance HyperMill MAXX; this offers three modules — for finishing, roughing and drilling — that are designed to provide significant boosts in
productivity.
Company owner Robert Heggemann says: “We are a service provider, structured to cover the entire process chain from development through to series production. Most of our customers are in the aerospace and automotive industry, and they value our expertise, reliability, flexibility and quality.”
The 220-employee company has a total of 18 milling, turning and ‘hybrid’ machines, with most coming from DMG Mori and Hermle. It is also ‘state of the art’ in terms of the software it uses. The manufacturing department uses a manufacturing execution system (MES) that complies with the latest Industry 4.0 standards, plus a product data management (PDM) system that manages customer data, as well as proprietary 2-D and 3-D CAD data. The company has used the HyperMill CAM system from Open Mind since 2009 and speaks highly of the MAXX machining-performance package that has recently been implemented.
Heggemann’s head of production, René Reiffer, says the ‘five-axis tangent plane machining’ strategy has left a lasting impression, as it offers enormous potential for savings. It was Open Mind technical sales consultant Dirk Lehmann who introduced Mr Reiffer’s milling team to the new software early in 2015, when he asked them to test the five-axis tangent plane machining strategy. “The result immediately won us over. We now use the five-axis tangent plane machining strategy as often as possible, as we can achieve a significant reduction in machining times,” says Mr Reiffer.
This finishing strategy is used in conjunction with a conical barrel-shaped cutter that was specially developed by Open Mind. It has a radius of more than 1m, allowing enormous ‘line increments’ to be used when finishing. Mr Lehmann says: “We regularly achieve time reductions of 70-90% in test workpieces, compared to when using traditional ball mills.
“We recently manufactured an aerospace component with 155mm-deep pockets and vertical walls. Historically, we would have milled it with a 12mm-diameter ball mill, which would have taken about 90min. Using the new method plus a barrel cutter with a lateral radius of 500mm and a tool radius of 4mm at the tip, the finishing process only took 15min. The surface finish in both cases was 3.2µm Rz.”
The time saving is primarily due to the enormous line increments (4mm during the final finishing pass) that can be programmed when using the barrel cutter. With a ball mill, it would be more than 10-times the number of lines (at a distance of 0.35mm). Mr Reiffer’s team also saves time when it comes to programming. It takes about 20min to create a finishing programme for a pocket like this with a ball mill; with five-axis tangent plane machining, programming takes just 5min.
The MAXX performance package also offers a high-performance cutting strategy for roughing. This allows users to achieve a maximum stock removal rate by ‘intelligently’ separating spiral and trochoidal-like tool-paths and dynamically adjusting the feed rate to suit the prevailing cutting conditions.
Furthermore, this strategy can be used for any type of machining operation, be it 2-D, 3-D or five-axis. Mr Reiffer says: “We mostly use it for 2-D components, as we can often machine these with the entire shank length of the tool. In such cases, we are two- to three-times faster — and we benefit from less tool wear.”