This standard specifies the mechanical properties of set screws and similar fasteners not under tensile stresses with nominal thread diameters from 1.6~24mm, which are made of carbon steel or alloy steel.
Attention shall be paid to that the mechanical and physical properties apply when tested at an ambient temperature will vary at higher or lower temperatures.
This standard does not apply to set screws requiring special properties such as
Specified tensile stresses (GB/T 3098.1);
Weldability;
Corrosion resistance (GB/T 3098.16);
Ability to withstand temperatures above +300℃ or below -50℃.
Note: set screws made from free-cutting steel should not be used above +250℃.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below.
GB/T 230-1991 Metallic Materials - Rockwell Hardness Test
GB/T 231-1984 Metallic Materials - Brinell Hardness Test
GB/T 3098.1-2000 Mechanical Properties of Fasteners - Bolts, Screws and Studs (idt ISO 898-1:1999)
GB/T 3098.16-2000 Mechanical Properties of Fasteners - Set Screws Made of Stainless Steel (idt ISO 3506-3:1997)
GB/T 4340.1-1999 Metallic Materials - Vickers Hardness Test - Part 1: Test Method (eqv ISO 6507-1:1997)
3 Designation System
The property classes are designated by the symbols shown in Table 1.
The numerical part of the symbol represents 1/10 of the minimum Vickers hardness.
The letter H in the symbol refers to hardness.
GB/T 3098 is consisted of the following parts under the general title of "Mechanical Properties of Fasteners":
GB/T 3098.1-2000 Mechanical Properties of Fasteners - Bolts, Screws and Studs
