Samputensili SH Series

Gear hobbing is the most productive process for producing cylindrical spur and helical gears. A hob — a helical cutting tool with multiple rows of cutting teeth arranged in a helical pattern around a cylindrical body — rotates continuously while the workpiece gear blank rotates in a synchronized ratio determined by the tooth count of the gear being cut. As the hob feeds across the face width of the gear, the synchronized rotation generates the involute tooth profile across the full face. A single hob can produce any number of teeth in its module range — making hobbing the most flexible and productive gear cutting process for cylindrical gears.

Dry hobbing uses no cutting fluid — the hob and workpiece operate in air, with heat managed by tool geometry, coating (TiAlN or AlTiN coatings on carbide hobs), and chip evacuation. Modern carbide hobs in dry conditions achieve cycle times comparable to wet hobbing while eliminating: oil cost, oil disposal (environmental compliance), fire risk, oil mist, and workpiece cleaning. Wet hobbing uses flood cutting oil for heat removal and tool life, and is still used for large-module gears where heat generation exceeds dry cutting capacity, or where HSS hobs (which tolerate less heat than carbide) are required.

The SH series accepts standard DIN 3972 or AGMA 1102 hob arbor mounting, supporting both solid carbide hobs (for small module fine-pitch gears), carbide-tipped hobs (for medium and large module), and HSS or HSS-PM (powder metallurgy high-speed steel) hobs across the module range. Samputensili has a tooling division (Star SU, Samputensili Cutting Tools) providing hob tooling matched to the machine's process parameters. Third-party hob suppliers including Sandvik, LMT Fette, and Gleason Cutting Tools also supply compatible hobs across the module and diameter range.

The SH series produces DIN 6 quality gears in production conditions with a well-maintained machine and appropriate hob tooling. DIN 5 is achievable with fine-pitch precision hobs, careful setup, and thermal-stable machining conditions. For automotive transmission gears requiring DIN 5 or better noise performance, the hobbed gear is typically followed by gear shaving (SH series machines can be configured for shaving too, or a dedicated shaving machine is used) or gear grinding (after heat treatment). Hobbing to DIN 6–7 provides the pre-heat-treatment blank geometry; finish quality is achieved in grinding.

Samputensili is an Italian gear cutting machine and gear tool manufacturer based in Bologna. Star SU is the North American partner company that distributes and services Samputensili machines in the US and Canada, providing local applications engineering, training, and parts support. United Grinding Group is the Swiss-based holding company that owns multiple precision grinding and gear machine brands including Studer, Schaudt, Mikrosa, Walter, Blohm, and has a strategic relationship with Samputensili/Star SU. This group structure provides Samputensili customers access to shared engineering resources and a broader service network than a standalone Italian manufacturer could support.