Strength-stress Life Of Helical Gear Teeth

Author:  Wellauer, E. J.
Source:  SESA, Vol. X, No. 2
Doc ID:  1953011
Year of Publication:  1953
Abstract:  
Any discussion on the interpretation and application of Test Data should have as its basic slogan: "Only one test can lead to a thousand mesleading opinions". This slogan is particularly applicable to tests involving fatigue. Many published tests and practical experiences have definently indicated that the service life of machine elements involves a broad scatter. The application of the data to designs depends mainly on whether a chouce shall be made on minimum or average life. The factor of safety to be applied certainly must consider the statistical quantity of the data beside the usual modifications made to accommodate service variables. Many industries produce products which can be tested in large numbers to quite definitely establish life ratings.This does not necessarily mean a narrow scatter band as attested by the wide spread between minimum, average and maximum life of precision made antifrictin bearings.