Hexagonal Bolt Size Specification Table Standard Table

 American bolts are a commonly used connection tool in mechanical engineering, construction engineering, and other industrial applications. The size specification table is an important standard for American bolts, used to specify parameters such as diameter, length, and number of threads for correct selection and use in design, manufacturing, and maintenance.

The size specification table for American bolts usually adopts two standards: Unified Coarse and Fine Thread (UNC) and Unified Fine Thread (UNF). UNC threads are used in most applications in general mechanical and construction engineering, with fewer threads per inch, making them more suitable for high-strength and heavy-duty applications; UNF threads are used in situations where tighter connections and finer adjustments are required, with a higher number of threads per inch, making them more suitable for applications in precision machinery and electronic equipment.

The following is a common size specification table (UNC and UNF) for American bolts:

UNC thread:

-1/4-20: Refers to a diameter of 1/4 inch with 20 threads per inch.

-5/16-18: Refers to a diameter of 5/16 inches with 18 threads per inch.

-3/8-16: Refers to a diameter of 3/8 inches with 16 threads per inch.

-1/2-13: Refers to a diameter of 1/2 inch with 13 threads per inch.

-5/8-11: Refers to a diameter of 5/8 inches with 11 threads per inch.

-3/4-10 refers to a diameter of 3/4 inches with 10 threads per inch.

-1-8: Refers to a diameter of 1 inch with 8 threads per inch.

UNF thread:

-1/4-28: Refers to a diameter of 1/4 inch with 28 threads per inch.

-5/16-24: Refers to a diameter of 5/16 inches with 24 threads per inch.

-3/8-24: Refers to a diameter of 3/8 inches with 24 threads per inch.

-1/2-20: Refers to a diameter of 1/2 inch with 20 threads per inch.

-5/8-18: Refers to a diameter of 5/8 inches with 18 threads per inch.

-3/4-16: Refers to a diameter of 3/4 inches with 16 threads per inch.

-1-14: Refers to a diameter of 1 inch with 14 threads per inch.

The above size specification table is not comprehensive, and other size specifications may be used in practical applications. In addition, the American National Standards Institute (ANSI) also specifies other types of American thread standards, such as American coarse pitch thread (NC) and American fine pitch thread (NF), each with their respective application scope and advantages that need to be selected based on specific applications.

Overall, the correct selection and use of American style bolts requires consideration of multiple factors, including stress, load, corrosion, temperature, and environmental factors. Choosing appropriate size specifications, materials, and coatings is crucial, and proper installation, tightening, and inspection according to relevant standards are also necessary to ensure the safety and reliability of bolted connections.