Cap nuts, also known as acorn nuts, protect threads by covering the exposed end of a bolt or threaded rod. This coverage serves several purposes:
1. **Physical Protection**: By enclosing the end of the bolt, cap nuts shield the threads from physical damage such as dents, nicks, or deformation that can occur from contact with other objects. This is crucial in maintaining the integrity of the threads for future use.
2. **Corrosion Resistance**: Cap nuts can be made from materials resistant to corrosion, such as stainless steel or brass. By covering the threads, they prevent exposure to moisture, chemicals, and other corrosive elements, thereby reducing the risk of rust and corrosion.
3. **Safety**: The rounded, smooth surface of a cap nut eliminates sharp edges, reducing the risk of injury from accidental contact. This is particularly important in environments where people might come into contact with the fasteners.
4. **Aesthetic Appeal**: Cap nuts provide a finished look to assemblies by hiding the protruding threads. This is often desirable in consumer products, furniture, and automotive applications where appearance is important.
5. **Contamination Prevention**: By sealing the end of the bolt, cap nuts help prevent dirt, dust, and debris from accumulating in the threads, which can complicate disassembly or adjustment.
6. **Vibration Resistance**: In some applications, cap nuts can help secure the bolt in place, reducing the likelihood of loosening due to vibrations. This is particularly useful in machinery and automotive applications.
Overall, cap nuts serve as a protective barrier, enhancing the durability, safety, and appearance of threaded assemblies.