BASIC KNOWLEDGE OF HEXAGON BOLTS

Hexagon bolts actually refer to fasteners consisting of a head with a screw. Bolts are mainly divided into iron bolts and stainless steel bolts according to material. Iron is divided into grades, with the common grades being 4.8, 8.8, and 12.9. Stainless steel is made of stainless steel SUS201, SUS304, and SUS316 bolts.
A complete set of hexagon bolts consists of a bolt head, a nut, and a flat gasket
Hexagon head bolts are hexagonal head bolts (partial threads) – c hexagonal head bolts (full threads) – c grade, also known as hexagonal head bolts (rough) hexagonal head bolts, black iron screws. The commonly used standards are mainly: sh3404, hg20613, hg20634, etc.
Hexagon head bolt (abbreviated as hexagon bolt) consists of a head and a threaded rod ( The comprehensive performance grades of bolts used for connection of steel structures are divided into more than 10 grades, including 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, and 12.9. Among them, bolts of grade 8.8 and above, which are made of low-carbon alloy steel or medium carbon steel and undergo relevant heat treatment (quenching and tempering), are generally referred to as high-strength bolts, while the rest are commonly referred to as ordinary bolts. The bolt performance grade mark consists of two parts of numbers that represent the nominal tensile strength value and yield ratio of the bolt material. The following is an example.
The meaning of bolts with a performance level of 4.6 is:
The nominal tensile strength of the bolt material reaches 400 mpa;
2. The yield strength ratio of bolt material is 0.6;
3. Nominal yield strength of bolt material up to 400 × 0.6=240MPa level
High strength bolts with a performance grade of 10.9, and the material after heat treatment reaches:
1. The nominal tensile strength of bolt material reaches 1000MPa;
2. The yield strength ratio of bolt material is 0.9;
The nominal yield strength of bolt material reaches 1000 × 0.9=900MPa level
The meaning of different grades of bolt performance is an internationally accepted standard. Bolts with the same product performance evaluation grade have the same performance regardless of their material and origin, and only the safety performance index grade can be selected for design.