The best book I have used that covers all the real basics in simple language is "GEARS" by H. E. Merrit, an English engineer, published by Pitman. I believe it is currently out of print, but a good library should be able to get a copy. It's treatmnt of bevels is a bit lacking, but they are a...
I assume 1 sun gear is fixed and o/all ratio is large. If this is the case, consider a propriety "harmonic" reducer. Correction of gears to achieve centre distance undermines tooth integrity too much especially if loads are large. I have had experience of just such a problematic drive which we...
I have the BSC Iron & Stell spec's and all the Japanese (JIS) spec's start with a capitalised 'S' followed by further capitalised letters and/or numbers. There is a J55 under the API spec's. Hope that helps,
Corrosion will induce cracks that can significantly reduce endurance limit. Up to 7x has been recorded. Check out:
http://www.epi-eng.com/BAS-Fretting.htm
http://www.epi-eng.com/RW-ShaftFatigue.htm
Is there any components mounted to the shaft in the fracture zone? If there is/are, is there any "coco" staining around the fracture zone. A helical fractute indicates the shaft failed in shear/torsion.
I concur with everybody vis-a-vis the alloy. Power capacity is directly proportional to hardness up to about 660Hv (thereafter it levels off) for contact stress and up to 350Hv for bending. For elevated hardnesses it is a little more complex for bending.
Establish the minimum hardness material...
Hi rob768, I believe the effective hardness should relate to the surface hardness. Some medium carbon steels would struggle to get much above 550Hv at the surface, never mind into the case.
Thanks unclesyd, I'm investigating a machine failure where the probable cause is inadequate flame hardening of a plate cam. The surface hardness at 60.5HRc is slightly over spec' (56-60HRc) but the hardness profile passes through the lower limit at only 0.5mm (0.02") deep. The case depth spec'...
I concur with gearguru's comment about EDM. You will though, be surprised to learn that in my experience, broaches are made closer to a radius than the involute. The errors are lost in the fit.
Don't go less than 1.2 CR. A 1.2 minimum CR accounts for geometry errors. The OD has a tolerance, the teeth have tolerences. I've worked in printing engineering for 40+ yrs. The paper will never come thro' the nip at the theoretical thicknes - that is a minimum! So there will be center distance...
