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 GEAR STRENGTH CALCULATIONS Post Reply Forum
 Posted by: bobthedog ® 04/19/2007, 10:34:09 Author Profile eMail author Edit Based on the lewis formula using stainless steel at 30 000 psi S = allowable unit stress for material at given velocity L = Maximum safe tangential load at pitch diameter in lbs Ss = allowable static unit stress for material psi V = velocity FPM at pitch diameter F face width of gear in inches Y = Outline factor P = diameteral pitch S = Ss x 600 ---- 600 + V PSI L = SFY --- pNow both this equations make sense but what is PSI thought that was the pressure in a car tyre isnt it? Is it a pressure measurement Static torque capacity Ts = LXP.D where P.D is pitch diameter in ozP.D = NO OF TEETH ---------- PITCH What do they mean by pitch? Pitch of what?? It has face width 3/16 of an inch how is that worked out how is 1/16 of an inch worked out?? The amount of this load distribution is dependent upon the contact ratio of the particular gears in mesh typical values are from 1.2 and 1.8 . 1.2 and 1.8 are the contact ratios but what does this mean exactly???? DONT GIVE UP THE FAITH