Bending tests
71.  The bending test-pieces shall withstand being bent, without fracture, through an angle of 180°. The internal radius of the bend shall not be greater than that specified in the following table:
Maximum specified tensile strength of forging
Internal radius of testing piece after bending
 
inch
Up to 32 tons per square inch
1/4
Above 32 tons and up to 36 tons per square inch
3/8
Above 36 tons and up to 40 tons per square inch
5/8