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Pinion Gear Contact Surface

Pinion Gear Contact Surface

Pinion Gear Contact Surface

Hi All,

I have a pinion gear (drive gear) and a ring gear (driven gear). I have attached a photo and marked up the contact pattern on the tooth.

Does the contact pattern appear correct? Should the contact area extend up to the tip?


RE: Pinion Gear Contact Surface


what's the story , did it fail prematurely? that pitting doesn't look good.
pattern looks proper.

RE: Pinion Gear Contact Surface

I agree with mfgenggear's comment. Pitting at low point of contact on the pinion tooth flank is an obvious problem. Adding some tip relief to the ring gear teeth might help.

RE: Pinion Gear Contact Surface

The pattern can look like that if the pinion teeth are intentionally longer than the gear teeth.

The extents of the contact pattern will vary with the degree of loading. If you operate the drive with large service factor, the contact pattern will be smaller.

RE: Pinion Gear Contact Surface

Just to add,
Two possibilities
#1) end of life for the pinion.
Surface fatigue failed causing pitting.
#2) surface duribility miscalculated.
The hardness of the pinion tooth. Flanks not hard enough.

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