Klingelnberg P 26

Face hobbing (Klingelnberg Cyclo-Palloid) and face milling (Gleason) are two distinct bevel gear cutting processes with different tooth geometries. Face hobbing: tool rotates continuously while the work rotates, creating a uniform tooth depth (parallel depth) gear with epicycloid tooth traces. Advantages: better contact ratio, smoother load transfer, preferred for high-speed automotive hypoid gears. Face milling (Gleason): each tooth space is individually indexed and cut with a face mill cutter, creating a tapered depth tooth. Advantages: simpler tooling, well-established tooling supply, more flexible for prototype and small batch. The two processes are not interchangeable - a gear designed for face hobbing cannot be machined on face milling equipment. Automotive OEMs typically specify the process based on their gear design standard (Klingelnberg or Gleason format).

KIMoS (Klingelnberg Integrated Manufacturing of Spiral Bevel Gears) is Klingelnberg's software platform that integrates gear design (tooth form calculation), machine setting generation (converting tooth geometry to machine kinematics), and quality feedback. Closed-loop operation: (1) Machine produces gear; (2) Gear is measured on a Klingelnberg gear measurement center (P 25, P 40); (3) Measurement deviations from theoretical are analyzed; (4) KIMoS generates corrected machine settings compensating for the measured errors; (5) Machine produces corrected gear. This closed-loop cycle typically converges to specification within 2-3 iterations, compared to 5-10 iterations with manual correction. For automotive production, closed-loop control is essential for maintaining gear quality within the tight AGMA quality specifications required for NVH performance.

Standard automotive bevel gear materials for the P 26: (1) 20MnCr5 (case-hardening steel) - most common for passenger car differentials; gear is cut soft, then case-hardened to 58-62 HRC, then lapped or ground. (2) 16MnCr5 - similar to 20MnCr5 for lighter-duty applications. (3) 17CrNiMo6 (carburizing steel) - for heavy-duty commercial vehicle differentials requiring maximum core toughness. Cutting parameters: cutting speed 60-120 m/min with TiAlN-coated high-speed steel (HSS) face hob cutters or carbide cutters for dry cutting. The P 26 standard is wet cutting with cutting oil for HSS tooling. The P 26 D (dry) variant uses carbide dry cutting without cutting oil for improved productivity and environmental compliance.

The P 26 integrates directly with Klingelnberg gear measurement centers (P 25, P 40, P 65) through the KIMoS software platform. After gear measurement, the CMM outputs deviation data in Klingelnberg format directly to KIMoS. KIMoS analyzes pitch error, profile error, lead deviation, and topological form deviations and generates the correction commands to the P 26 machine settings. This integration works without manual data re-entry. For automotive production with 100% inspection requirements, a P 26 + KIMoS + measurement center combination operates with automated part transfer between machines in a closed manufacturing cell. Klingelnberg offers complete integrated gear manufacturing cell design with material handling between cutting and measurement.

For a typical passenger car ring gear (190 mm diameter, 38 teeth, 20MnCr5 soft): cycle time approximately 60-90 seconds per gear in wet hobbing. For the mating pinion (60 mm, 10 teeth): approximately 30-45 seconds. A matched differential set (ring gear + pinion + two side gears + two spider gears): approximately 5-8 minutes per set complete hobbing cycle. Production capacity: 60-100 ring gear/hour, 30-50 matched sets/hour. At 50 sets/hour x 2 shifts x 250 days: 500,000 differential sets/year from one P 26. This is the production rate for soft-hobbed gears before heat treatment and subsequent hard finishing (lapping or grinding) on separate machines.