The Guide: Fasteners Thread Series

Threaded Fasteners are mostly used for a multitude reasons. Apart from being string and having strength benefits the fasteners are also reversible; which means that they can be easily taken apart after being assembled.

They are cost effective and are available in wide range of sizes. The fasteners threads have collection of ridges in the form of helix on internal and external face. Internally threaded fasteners are nuts while externally threaded ones are bolts, screws and studs.

Types of Threaded Fasteners

1.    Unified National Coarse Threads (UNC) - These are most common and general fasteners thread. They have high tolerance for manufacturing and plating.

2.    Unified National Fine Threads (UNF) - The nuts and bolts have better torque locking and load carrying ability. They have tighter tolerance, finer adjustment and are commonly used in Aerospace Industry.

3.    United National Extra Fine Thread (UNEF) - Finer then UNF thread. They are used in applications with tapped holes in hard material as well as tapped holes in thin materials.

4.    UNJC and UNJF Threads - Two types of “J” threads are there: internal and external. External threads have larger root radius resulting in larger tensile area and small stress concentration.

5.    UNR and UNK Threads - UNR threads and UNK threads have only difference with root radius.

6.    Constant-Pitch Threads - There is variety of such threads as they come in various diameters to fit in applications.

At UPS Lakshmi, we understand all the fastening requirements. With high quality production UPS has earned the trust of their customers and established itself in the international market.