Blog

Hardness classes and advantages of hexagon bolts

Hardness classes and advantages of hexagon bolts

The so-called hexagon socket bolt refers to the hexagon socket head shaped cylinder head, which can also be called hexagon socket head screw. The commonly used hexagon socket bolts are of class 4.8, class 8.8, class 10.9 and class 12.9. We can choose different classes of hexagon bolts according to the different needs of customers, so as to play a more beneficial role in the performance of bolts. According to the Understanding of the Chinese standard parts network, tell you about the hardness of hexagon bolts have what.

Hardness level
Hexagon bolts according to the hardness of the screw wire, carrying tension, yield strength is a class classification, namely the class of hexagon bolts, hexagon bolts is what class. Different grades of hexagon socket bolts are required for different products and materials. All hexagon socket bolts have the following grades:
The inner hexagon bolts are divided into ordinary and high - strength bolts according to grade strength. Ordinary hexagon bolts refer to class 4.8, and high-strength hexagon bolts refer to class 8.8 and above, including class 10.9 and class 12.9. Class 12.9 hexagon socket bolts shall generally refer to black hexagon cup head screws with krollers in natural color and oil.
There are more than 10 grades of inner hexagon bolts for steel structure connection, such as 3.6, 4.6, 4.8, 5.6, 6.8, 9.8, 10.9, 12.9 and so on. Among them, the bolts of grade 8.8 and above are made of low carbon alloy steel or medium carbon steel, and after heat treatment (quenching and tempering), they are generally referred to as high-strength bolts, and the rest are generally referred to as ordinary bolts. The bolt performance grade is composed of two parts, which respectively represent the nominal tensile strength value and the flexural strength ratio of the bolt material.

Level of performance
The bolt performance grade is composed of two parts, which respectively represent the nominal tensile strength value and the flexural strength ratio of the bolt material. For example, for bolts with a performance grade of 4.6, the meaning is:
1. The nominal tensile strength of the bolt is up to 400MPa;
2. The bending strength ratio of bolt material is 0.6; The nominal yield strength of the bolt material is 400×0.6=240MPa.
Performance grade 10.9 high strength bolts, the material after heat treatment can reach:
1. The nominal tensile strength of the bolt is up to 1000MPa;
2. The bending strength ratio of the bolt material is 0.9; The nominal yield strength of the bolt material is 1000×0.9=900MPa.
The meaning of performance grade of inner hexagon bolt is international and universal standard, the bolt of same performance grade, regardless of the difference of its material and producing area, its performance is same, choose performance grade only on the design can.
The grade that inside hexagon bolt divides basically was like this, the price on grade is different certainly also on the market. General high strength inner hexagon bolts are certainly higher than the price of ordinary inner hexagon bolts. In the market, there are still four kinds of grades: 4.8,8.8,10.9 and 12.9.

Use advantage of hexagon socket bolt
1. It can bear a larger load. Its bearing surface has six, compared to only two sides of the word screw and cross screw more bearable.
2.Hexagon bolts in use can be countersunk, that is, the whole nut is sunk to the inside of the workpiece, can keep the surface of the workpiece flat, beautiful.
3. Easy installation.
Relative to the hex screws, hexagon is suitable for more assembly occasions, especially narrow occasions, so it is very convenient assembly and maintenance, debugging is also convenient.
4. Not easy to disassemble.
We usually commonly used tools are adjustable wrench, screwdriver and spanner, etc., and the removal of hexagon bolts must use a special wrench, so, the general people are not easy to remove, this is also a benefit. Of course, if you struggle, can be designed into a variety of strange structure, the problem is, special spanner is not good manufacturing.

0 Comments
Leave a Comment
Your email address will not be published. Required fields are marked *
Submit Comment
Concact Us Now
Screw Manufacturers, Bolt Manufacturers, Nut Manufacturers - Oukailuo
No.26 Zhijiang Road, Lanjiang Street, Yuyao City, Zhejiang Province, China 315400
You can trust us
Ningbo OuKaiLuo Hardware Co., Ltd, established in 1999, has been a leading manufacturer and supplier of fasteners. Our main export market is North America, Europe, Oceania, Korea and so on.
© 2019 OuKaiLuo    RELATED ARTICLES        SiteMap.html    SiteMap.xml
Marketing Support by Globalsir
Enter your inquiry details, We will reply you in 24 hours.
Name can't be empty
E-mail can't be empty
Company can't be empty
Phone can't be empty
Products can't be empty
Message can't be empty
Verification code error
code
Refill