Standar for Bolt

Grade

Bolt Size

Tension Stength

Yield Strength

Enlogation

Hardness

Head Marking

in.

ksi

ksi

%

Brinell

Rockwell C

A490

type1

1/2~1"

150-173

130min

14

<2*D, HB 311-352；>2*D, HB…-352;

<2*D, 33-39；>2*D, HC…-39;

1~1-1/2"

150-173

130min

14

<3*D,HB313-352；>3*D,HB…-352

<2*D, 33-39；>2*D, HC…-39;

type3