Tornillos de enchufe de alta resistencia 5/16"" 3/8"" 1/2"" BSW Whitworth cabeza de pernos tornillos de enchufe

They are a BS 2470:1973. The technical data for the material is that it is high tensile grade alloy steel, heat treated to RC39-43. The material has a tensile strength of 190.000 ibf/in2 to 180.000 ibf/in2, a yield strength of 170.000 ibf/in2 to 162.000 ibf/in2, and a shear strength of 114.000 ibf/in2 to 108.000 ibf/in2.

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