What does SFC stand for on a bolt?
Keeping this in view, what do the letters on bolts mean?
The lines on the head of a bolt indicate its grade. SAE J429 (Society of Automotive Engineers) bolts have radial lines, whereas ASTM (American Society for Testing and Materials) uses a combination of letters and numbers to indicate the grade.
Additionally, what is the meaning of 8.8 grade in a bolt? 8.8 is ISO 898–1 grading for Bolts and screws. It indicates a bolt/screw with tensile strength of minimum 800MPa and a yield strength of 80% of 800MPa = 640MPa. Depending on thickness these are either quenched and tempered or can also be used without Q&T provided they meet the hardness and tensile requirements.
Similarly, what are the markings on a bolt head?
Bolt heads and nuts are often marked with numbers, letters, dashes, slashes, dots, or an assortment of other marks. Fasteners commonly have two different markings: a unique manufacturer identification symbol – such as letters or an insignia – and information about the fastener strength.
What is the strongest bolt grade?
The strongest commercial-quality bolt is grade 8, marked by six raised dashes; its medium-carbon alloy steel has been quenched and tempered to achieve a tensile strength of 150,000 psi.