News

Home / News / Classification of hex nuts

Classification of hex nuts

Hex nuts are classified into Type I, Type II, and Thin according to the nominal thickness. Nuts of class 8 or higher are divided into two types, type 1 and type II.
  The Type I hex nut is the most widely used, and the Type 1 nut is divided into three grades A, B, and C. The Grade A and Class B nuts are suitable for machines, equipment, and structures with low surface roughness and high precision.

Class C nuts are used on machines, equipment or structures where the surface is rough and the precision is not high. Type 2 hex nuts are thicker and are often used in applications where assembly and disassembly are often required.  Type 1 nut refers to a common hex nut with a nominal nut height of m ≥ 0.8D, and its type size should meet the requirements of GB/T6170;
  The height of the type 2 nut is higher than that of the type 1 nut, and the type size should conform to GB/T6175. There are two purposes for adding a type 2 nut: one is to obtain a relatively inexpensive nut by increasing the height of the nut.
  Because the 8 grade 1 nut of D ≤ M16 does not need heat treatment, among the 8 grade nuts, only the type 2 nut is used for the specification of D > M16~39.
It is clear that the type 1 nut that is not heat treated does not meet the mechanical performance requirements of the class 9 nut. Another purpose of the Type 2 nut is to obtain a 12-stage nut with better toughness. As the height of the nut increases, the guaranteed stress index can be achieved at a lower quenching and tempering hardness, thus increasing the toughness of the nut.

Be the First to Know

For exclusive deals and latest offers, sign up by entering your email address below.