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Understanding the Difference Between UN and UNC: A Detailed Comparison
When it comes to screws, bolts, and other fasteners, understanding the different types of threads is crucial. Two of the most common types are UN and UNC. In this article, we’ll delve into the details of these threads, highlighting their differences and applications.
What is UN?
UN, which stands for Unified National, is a type of thread used in the United States. It is a standard thread series that is widely used in various industries. The UN thread has a 60-degree thread angle and a flat bottom, which makes it suitable for a wide range of applications.
UN threads are available in different series, including UN, UNF, UNEF, and UNJ. Each series has its own characteristics and applications. For example, UNF threads are fine-pitch threads, while UNEF threads are extra fine-pitch threads. UNJ threads, on the other hand, are a special type of thread with a 55-degree thread angle.
What is UNC?
UNC, which stands for Unified National Coarse, is another type of thread used in the United States. It is a coarse-pitch thread series that is commonly used in the production of fasteners. UNC threads have a larger thread angle and a larger pitch compared to UNF threads.
UNC threads are available in different sizes and pitches, making them suitable for various applications. They are often used in applications where a coarse-pitch thread is required, such as in the construction of machinery and vehicles.
Difference Between UN and UNC
Now that we have a basic understanding of UN and UNC threads, let’s compare them in more detail.
| Parameter | UN | UNC |
|---|---|---|
| Thread Angle | 60 degrees | 60 degrees |
| Pitch | Varies | Coarse pitch |
| Application | General-purpose applications | Coarse-pitch applications |
As you can see from the table, the main difference between UN and UNC threads is the pitch. UN threads have a variable pitch, while UNC threads have a coarse pitch. This makes UNC threads suitable for applications where a coarse-pitch thread is required.
Applications of UN and UNC Threads
UN and UNC threads are used in a wide range of applications. Some of the most common applications include:
- Machine tools
- Automotive components
- Construction equipment
- Electrical equipment
UN threads are often used in general-purpose applications, while UNC threads are used in applications where a coarse-pitch thread is required.
Conclusion
Understanding the differences between UN and UNC threads is crucial for selecting the right thread for your application. By knowing the characteristics and applications of these threads, you can ensure that your fasteners are suitable for your specific needs.