What is the hex bolts?

                                                   What is the hex bolt?

Hex bolt

fastener composed of head and bolts.

Performance level

The performance grades of bolts used for steel structure connection are divided

 into more than 10 grades, including 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9, etc., 

of which the bolts of grade 8.8 and above are made of low carbon alloy steel or

 medium carbon steel and heat treated (quenched and tempered), which are generally 

referred to as high-strength bolts, and the rest are generally referred to as ordinary 

hexagon bolts. The bolt performance grade mark consists of two parts of numbers, 

which respectively represent the nominal tensile strength value and yield strength ratioof the bolt material.

Advantage

Outer hexagon bolt/screw: good self-locking; Large pre-tightening contact area

and large pre-tightening force; The length range of full thread is wider; There can 

be reamed holes, which can fix the position of parts and bear the shear caused by 

transverse force

Application

Take the car as an example. At the connection position between the subframe and the

 body, several bolts pass through the subframe through the bottom and are tightened 

to the body. Because the bottom is an invisible area, there is no aesthetic requirement, 

there is no interference in tightening, and the axial force and torque required for tightening 

are large (the bolts are tightened after yielding). For this connection position, the outer hexagon bolts are suitable for tightening.