Gear Technology Magazine

Hainbuch Produces Large Mandrel With Significant Clamping Range for China

July 9, 2007

Hainbuch GmbH produced a workholder that weights 1.3 tons and features a clamping range of up to 420 mm.

According to the company's press release, the mandrel was developed for a Chinese transmission and motor manufacturer and can clamp a gear with an OD of 1m. According to Hainbuch's press release, the customer solicited a user-friendly solution that did not require adjustment of various clamping devices.

The CENTREX system in the segmented mandrel automatically adjusts during the changeover and guarantees exact repeatability. The mandrel has a segmented bushing equipped with a specially-developed rubber compound and can clamp gears with an outer diameter of up to 1 meter with concentric precision of the Gleason-Pfauter hobbing machine. In internal tests, repeatability was less than 0.005 mm.

Peter Gerster, section manager in the production department, says "The greatest challenge was not only the large clamping range, but the coordination of various processes we were unable to carry out internally. More than 200 production orders, the engineering by our team of experts for the end-stop production and nearly 200 external order items from raw material to the welding construction and heat treat--all of that has to be managed and the timing has to be right in the end."