1/2-20 UNF-2B Thread Dimensions
Overview
The 1/2-20 UNF-2B thread is a type of thread commonly used in various industries, including aerospace, automotive, and construction. It is a coarse thread with a thread diameter of 1/2 inch and 20 threads per inch. The "UNF" abbreviation stands for "Unified National Fine" and "2B" refers to the thread class.
Thread Dimensions
The following are the dimensions for a 1/2-20 UNF-2B thread:
Major Diameter
- Nominal: 0.500 inch (12.7 mm)
- Maximum: 0.502 inch (12.74 mm)
- Minimum: 0.498 inch (12.65 mm)
Pitch Diameter
- Maximum: 0.446 inch (11.31 mm)
- Minimum: 0.438 inch (11.11 mm)
Minor Diameter
- Maximum: 0.391 inch (9.93 mm)
- Minimum: 0.383 inch (9.72 mm)
Thread Length
- Minimum: 0.875 inch (22.23 mm)
- Maximum: 1.250 inch (31.75 mm)
Thread Angle
- 60 degrees
Thread Class
- 2B (medium fit)
Tolerance
The following are the tolerance values for a 1/2-20 UNF-2B thread:
Major Diameter
- Plus: 0.002 inch (0.051 mm)
- Minus: 0.001 inch (0.025 mm)
Pitch Diameter
- Plus: 0.001 inch (0.025 mm)
- Minus: 0.001 inch (0.025 mm)
Minor Diameter
- Plus: 0.002 inch (0.051 mm)
- Minus: 0.001 inch (0.025 mm)
Applications
The 1/2-20 UNF-2B thread is commonly used in various applications, including:
- Aerospace industry for fastening structural components
- Automotive industry for engine and transmission components
- Construction industry for fastening structural components
- General industrial applications for machinery and equipment
Conclusion
In conclusion, the 1/2-20 UNF-2B thread is a widely used thread type with specific dimensions and tolerances. Understanding these dimensions and tolerances is crucial to ensure proper fit and functionality in various applications.
