STANDARD BOLT IDENTIFICATION MARKINGS

← Back to document page

Proof Load(psi)Yield StrengthMin (psi)Tensile StrengthMin (psi)Low or Medium Carbon Steel1/4 THRU 1 33,00036,000Low CarbonSteel1 4 thru 4 SAE J429Grade 2Low or Medium Carbon Steel1 4 thru 3 4Over 3 4 thru 1 55,00033,00057,00036,00074,00060,000 No Grade MarkSAE J429Grade 4StudsMedium Carbon Cold Drawn Steel1 4 thru 1 100,000115,000Low or Medium Carbon Steel1/4 THRU 1 33,00036,000Low CarbonSteel1 4 thru 4 Low or Medium Carbon Steel1 4 thru 3 4Over 3 4 thru 1 55,00033,00057,00036,00074,00060,000ASTM A193Grade B5Bolts, Screws, Studs forHigh Temperature ServiceAISI 5011 4 thru 4 80,000100.

Proof Load (psi) Yield Strength Min (psi) Tensile Strength Min (psi) Low‐ or Medium‐ Carbon Steel 1/4 THRU 1 ½ 33,000 36,000 Low‐Carbon Steel