„Tool life 26m per active hob tooth, 17’000 parts produced per resharpening“
| Application | Car Gear Box Manufacturing | |
| Customer request | Reduction of cost per part maintaining the same cycle time, dry finish hobbing before heat treatment, in DIN quality class 7 | |
| Suggested solution by Schnyder | Replacement of PM steel hob with solid carbide nanograin hob. | |
| Component / tool | ||
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| Component / gear data | 31 tooth spur gear, DP12 (M2.1167) – 20° PA, external Ø70.3mm, useful length 17mm, material 16MnCr5 with 630 N/mm2 | |
| Hob specification | Shank type gear hob: Ø80 x 273/ 200 – shank Ø32/ SK30 - 19 gashes, Nanograin solid carbide (AAA) / 2 RHS Coating: Alcrona |
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| Process | First cut: h 4.60mm in climb cutting vc 280 m/min. / fa 1.80 mm/R Second cut: h 5.125mm conventianal cutting vc 400 m/min. / fa 1.20 mm/R chip thickness ca. 0.10- 0.13mm |
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| Hobbing machine | Pfauter P210 CNC | |
| Resultat | # of parts produced per resharpening: 17‘000 pcs (!) # of resharpenings: 25 Total cutting length: 151‘000 m Chip volume: 6‘300 mm3/piece Total # of hob teeth: 285 # of active hob teeth: 238 Tool life: 26 m / active hob tooth |
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| Achieved gear quality with new hob | ||
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| Achieved gear quality after 13'000 parts (wear of 0.05mm) | ||
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| Customer benefit | Tool life of PM steel hob: 2'000 parts per resharpening. Achieved tool life with Schnyder solid carbide hob: 17'000 parts per resharpening. Benefit: - lower cost per part - longer tool change interval |
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