What are the grade standards for hexagonal nuts?

The grade standards for hexagonal nuts mainly include the following aspects:

1. Product grade
The product grade of hexagonal nuts is mainly divided according to the thread tolerance grade. Common grades are A, B, and C.

Grade A: Suitable for machines, equipment or structures with smooth surfaces and high precision requirements. Grade A nuts are usually used for high-strength connections above grade 8. They have high precision and are suitable for important places with high assembly precision and places subject to large impact, vibration or variable loads.
Grade B: Suitable for machines, equipment and structures with small surface roughness and high precision requirements, but their precision is slightly lower than that of grade A. Grade B nuts are often used for connections below grade 8.
Grade C: Used for machines, equipment or structures with relatively rough surfaces and low precision requirements. Grade C nuts are rough bolts, generally used for shear connections of secondary structures or temporary fixation during installation.

2. Strength grade
The strength grade of hexagonal nuts is also one of its important performance indicators. Common strength grades include 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9, etc. These grades represent the performance indicators of nuts such as tensile strength and yield strength.

3. Other classifications
In addition to product grades and strength grades, hexagonal nuts can also be classified according to other standards, such as:

According to nominal thickness: divided into type I, type II and thin types. Type I nuts are the most widely used, type II nuts are thicker and are mostly used in occasions where they are often required to be assembled and disassembled, and thin nuts are mostly used in occasions where the surface space of the connected parts is limited.
According to tooth pitch: divided into standard teeth, regular teeth, fine teeth, ultra-fine teeth and reverse teeth, etc.
According to material: divided into stainless steel hexagonal nuts, carbon steel hexagonal nuts, copper hexagonal nuts, iron hexagonal nuts, etc.
According to usage: divided into hot-melt copper nuts, hot-pressed copper nuts, embedded copper nuts and ultrasonic copper nuts, etc.

4. Specific standards
The specific standards for hexagonal nuts include multiple national standards and industry standards, such as GB/T 6170 (type 1 hexagonal nut), GB/T 6175 (type 2 hexagonal nut), GB/T 6172 (hexagonal thin nut), etc. These standards specify the requirements for the size, tolerance, material, performance, etc. of the nut.

The grade standards of hexagonal nuts involve multiple aspects, including product grade, strength grade, nominal thickness, pitch, material, and usage methods. When selecting and using hexagonal nuts, the appropriate grade and standard should be selected according to the specific application scenarios and requirements.

#6-3/8 M5-M36 Single Chamfered Hexagon Nuts