Cylindrical head hexagon screws, also referred to as hexagon bolts, cup head screws, hexagon screws, its name is not the same, but the meaning is the same. Commonly used hex socket cylindrical head screws, there are 4.8, 8.8, 10.9, 12.9. Also called hex socket screw, also called hex socket bolt. Its head is hexagonal, also cylindrical head. There are stainless steel and iron according to the material. Stainless steel SUS202 hexagonal head screws, this is stainless steel ordinary material, stainless steel SUS304 hexagonal head screws, stainless steel SUS316 hexagonal head screws. Iron according to the hex head screw strength grading, there are 4.8 hex head screws, there are 8.8 hex head screws, there are 10.9 hex head screws, there are 12.9 hex head screws. Class 8.8 -12.9 hexagon socket head screws are called high strength and high grade hexagon socket bolts.

Performance requirements edit broadcast

1. Nominal tensile strength of bolt material reaches 400MPa;

2. The compressive strength ratio of bolt material is 0.6; The nominal yield strength of bolt material is 400×0.6=240MPa.

Performance grade 10.9 high strength bolts, the material after heat treatment, can achieve:

1. Nominal tensile strength of bolt material reaches 1000MPa;

2. The compressive strength ratio of bolt material is 0.9; The nominal yield strength of bolt material is 1000×0.9=900MPa.

Inside the meaning of hexagon bolt performance grade is international standard, the bolt of same performance grade, no matter its material and the distinction of producing area, its performance is identical, choose performance grade only on the design can.

The grade division of inner hexagon bolt is basically such, the grade is different, the price on the market is certainly different. General high strength hex bolt is certainly much higher than the price of ordinary hex bolt. Generally used in the market more or 4.8, 8.8, 10.9, 12.9 these four.
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