In 1949, Karl Heilmeier and Wilhelm Weinlein started their business of "manufacturing hydraulic equipment". What began modestly developed into a success story over the years: further products and new locations were added step by step. Today, the Hawe Group, headquartered in Aschheim near Munich, employs around 2,500 people. Five years ago, a new plant with 30,000 square meters of production space was built on a greenfield site near Kaufbeuren. In Kaufbeuren, 540 employees generate an annual turnover of around 100 million euros. Proportional, load-holding and lifting valves are produced in up to three shifts. These are used in the hydraulics of construction and agricultural machinery, in tipper trucks and in municipal vehicles. Hawe implements a high level of vertical integration and produces a large number of variants.

"The entire flow of goods takes place in Kaufbeuren, from prefabrication to fine machining and assembly," explains Thomas Schmid, Head of Rotating Parts and Prefabrication. An important issue is traceability, which is ensured by the documented inspection of all components. The company sets high quality standards in order to meet the requirements of its customers, the users. "These are key challenges alongside top delivery performance, functionality and the robustness of our components," he says.

In search of improvements

In this context, a continuous improvement process is being implemented in Kaufbeuren and production processes are being put to the test in all departments. This also applies to the machining of control pistons made of case-hardened steel for hydraulic blocks, where the employees identified potential for improvement. "We were not satisfied with the service life of the special grooving plate with two radii used by a competitor. Five steps were required for grooving," explains Andreas Volmer, production planner at Hawe. In search of a more efficient solution, the Allgäu-based company finally turned to Iscar. Dirk Moosreiner, Application Technology and Consulting, Detlef Ossadnik, Consulting and Sales, and Uli Köhler, Regional Sales Manager, took on the matter and analyzed the process. "We were convinced that we could manufacture the part in just one step," says Detlef Ossadnik, and Uli Köhler adds: "In combination with targeted cooling, we were aiming for a significant increase in tool life." These statements initially met with skepticism from Andreas Volmer. "The component is widely stretched. I feared that there might be too much cutting pressure." To clarify the situation, on-site tests were arranged.

Machining with high cutting values

The Iscar experts suggested the special PENTA CUT 27 cutting insert, on which a special contour was ground. "The tool has five cutting edges and offers a very good price-performance ratio per cutting edge. The very stable clamping enables machining with high cutting values," explains Uli Köhler. The cutting edges have a ground chip former for the formation of easy-to-control chips. This has a positive effect on precision and surface quality. Process reliability is also guaranteed: If a cutting edge breaks, PENTA CUT can continue to be used without any problems.

Together with the machining experts from Hawe, Dirk Moosreiner carried out comparative tests on the machine. Machining was carried out at a cutting speed of 120 meters per minute and a feed rate of 0.05 millimeters per revolution. Iscar's target was 5,000 parts - the test results were higher. "We machined 15,000 components without the tool showing any wear," explains Dirk Moosreiner. Only 2,500 parts were possible with the competitor's solution. Fears regarding excessive loads during the process were also dispelled. "Despite a relatively large cutting width of 20 millimetres, the cutting pressure was optimal," explains Detlef Ossadnik. The results impressed the Kaufbeuren-based company.

Long service life and fast processing

What the tests had indicated was confirmed in practice: the special grooving plate from Iscar fully meets HAWE's expectations. "We are delighted with the long tool life, which has significantly reduced tool and process costs. Whereas previously 33 indexable inserts were required per year for this type of machining, two are now sufficient. We also save time because the machining time per component has been reduced by 27 percent," summarizes Andreas Volmer. Producing the contour in a single step is a reliable process and corrections in the machine are not necessary. "We also achieve good and stable shape and position tolerances," says Andreas Volmer. Hawe also rates the chip formation positively. "The targeted coolant supply reliably guides the chips away from the workpiece," adds Thomas Schmid.