NF ISO 6336-2
Calculation of load capacity of spur and helical gears - Part 2 : calculation of surface durability (pitting)
This document specifies the fundamental formulae for use in the determination of the surface load capacity of cylindrical gears with involute external or internal teeth. It includes formulae for all influences on surface durability for which quantitative assessments can be made. It applies primarily to oil?lubricated transmissions, but can also be used to obtain approximate values for (slow?running) grease?lubricated transmissions, as long as sufficient lubricant is present in the mesh at all times.The given formulae are valid for cylindrical gears with tooth profiles in accordance with the basic rack standardized in ISO 53. They can also be used for teeth conjugate to other basic racks where the actual transverse contact ratio is less than ??n = 2,5. The results are in good agreement with other methods (see References [5], [7], [10], [12]).These formulae cannot be directly applied for the assessment of types of gear tooth surface damage such as plastic yielding, scratching, scuffing and so on, other than that described in Clause 4.The load capacity determined by way of the permissible contact stress is called the "surface load capacity" or "surface durability".If this scope does not apply, refer to ISO 6336-1:2019, Clause 4.
This document specifies the fundamental formulae for use in the determination of the surface load capacity of cylindrical gears with involute external or internal teeth. It includes formulae for all influences on surface durability for which quantitative assessments can be made. It applies primarily to oil?lubricated transmissions, but can also be used to obtain approximate values for (slow?running) grease?lubricated transmissions, as long as sufficient lubricant is present in the mesh at all times.
The given formulae are valid for cylindrical gears with tooth profiles in accordance with the basic rack standardized in ISO 53. They can also be used for teeth conjugate to other basic racks where the actual transverse contact ratio is less than ??n = 2,5. The results are in good agreement with other methods (see References [5], [7], [10], [12]).
These formulae cannot be directly applied for the assessment of types of gear tooth surface damage such as plastic yielding, scratching, scuffing and so on, other than that described in Clause 4.
The load capacity determined by way of the permissible contact stress is called the "surface load capacity" or "surface durability".
If this scope does not apply, refer to ISO 6336-1:2019, Clause 4.
ISO 6336-2:2006 specifies the fundamental formulas for use in the determination of the surface load capacity of cylindrical gears with involute external or internal teeth. It includes formulas for all influences on surface durability for which quantitative assessments can be made. It applies primarily to oil-lubricated transmissions, but can also be used to obtain approximate values for (slow-running) grease-lubricated transmissions, as long as sufficient lubricant is present in the mesh at all times.
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1 Domaine d'application
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2 Références normatives
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3 Termes, définitions, symboles et termes abrégés
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4 Endommagement par écaillages et coefficients de sécurité
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5 Formules de base
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6 Facteur géométrique, Z H, et facteurs de contact, Z B et Z D
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7 Facteur d'élasticité, Z E
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8 Facteur de rapport de conduite, Ze
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9 Facteur d'angle d'hélice, Zß
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10 Tenue en fatigue à la pression de contact
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11 Facteur de durée de vie, Z NT (pour les flancs)
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12 Influences du film lubrifiant, facteurs Z L, Z v et Z R
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13 Facteur d'écrouissage, Z W
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14 Facteur de dimension, ZX
- Bibliographie
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