List of commonly used thread standards in my country

National standards of thread commonly used in China

Threads, which are one of the mechanical fasteners, are used to fasten, adjust and adjust parts, with the advantages of being able to adjust the width of the hole and install more parts at the same time. In addition, depending on the type of thread and its size, strength can also be increased. In China, the design and application of threaded components are determined by the standards, which helps maintain quality control. There are a variety of standards for threaded components available in China, including international standards and Chinas national standards.

International standards:

The most internationally renowned standards are UNC and UNF. UNC (Uniform Coarse Thread) is a regular coarse thread, also referred to as local thread. This thread is mainly used in machinery and machinery components. UNF (Uniform Fine Thread) is a regular fine thread, also referred to as precision thread. The UNF standard is mainly used in precision products and instruments.

China’s National Standards:

In addition to international standards, China also has its own national standards. Some of the most common are GB, MJ and HG. GB is short for General Thread. It is mainly used for coarseness, medium and fine thread. MJ is short for Metric Thread. It is mainly used for thin wall metric thread and fine thread. HG is short for Highland Thread. It is mainly used for cylindrical thread and taper thread.

Thread Types and Terminology:

There are two types of threads, external and internal. An external thread refers to a thread outside of a hole, and an internal thread refers to a thread inside of a hole.

Thread terms are also used to describe specific characteristics of threads, including:

1) Pitch: the distance from one thread to the next. This is expressed in millimeters (mm) or threads per inch (TPI).

2) Major diameter: the uppermost and largest diameter of a thread.

3) Minor diameter: the end diameter of the thread.

4) Flank angle: the angle of the side walls of the thread.

5) Helix angle: the angle of the thread, when in a cutaway view.

Conclusion

Threads have a long history of use in China, and the use of international and national standards to set design and application rules has led to better quality control. There are two types of threads and various terms used to describe their characteristics. Through proper use and understanding ofthread standards, it becomes easier to create high quality, reliable threaded components.

Our country often used screw standard overview

Screws are one of the most commonly used fasteners. Without proper standards, it is difficult to guarantee quality and interchangeability. Therefore, it is extremely important to select the right standard for screws.

The British Standard for screws is: BS 84. The sizes of screws specified in this standard are probably the most commonly used metric and imperial screws in the UK. The majority of commercial products acquired in the UK will typically conform to the following dimensions and grades.

The British Standard is the most widely used standard for machine screws, brass screws, countersunk screws and other screws.

Common metric screw standards used in China are: GB/T 3098.1-1996,GB/T 7307-2001,GB/T 7307-2005 and GB/T 7307-2014.It specifies the classification,code and size,mark and grade,dimension,tolerance and design description of the diferent types of screws.

The American-standard screws commonly used in China are: ANSI/ANSI B18.6.1-1981, ANSI/ASME B18.6.3-2003, ANSI/ASME B18.6.4-2008 and ANSI/ASME B18.6.9-2007.These standards provide information on the nominal diameter,head shape and size,thread pitch,strength grade and other requirements for machine screws,cap screws,tapping screws and self-drilling tapping screws.

The Japanese standard for screws is JIS B1176-1993.It specifies the classification,code and size,mark and grade,dimension and tolerance and design description for metric machine screws.

The above are the most commonly used standard for screws in China.They form the basis for the manufacture and use of screws of good quality and interchangeability.