This specification covers the grain flow pattern requirements in headed bolts@ screws@ and studs. The heading practice in the manufacture of the bolt@ screw@ or stud sets the grain flow pattern@ but it is also greatly influenced by the fastener design.
SAE USCAR8-2007 history
2019SAE USCAR8-4-2019 GRAIN FLOW PATTERN FOR BOLTS, SCREWS, AND STUDS