Coupling Nut - Features And Applications

Coupling Nut:

A ‘Coupling Nut’, also known as ‘Long Nut’ is a long threaded ‘Fastener-Nut’ used for joining two male threaded fasteners, most commonly a ‘Stud’ which is also a relatively long rod. The coupling fastener is a hex shaped nut that can be tightened & loosened with a handheld wrench. 

These nuts are manufactured using a cold forged and hot forged technique depending on its applications. The coating used for these nuts is Electro-Zinc Plating, hot dip galvanizing; phosphate coating, silver plating, chrome plating and many other coatings are also done.  

A Coupling Nuts length varies from 3mm to 20mm clearly giving a firm grip to the threaded rods. So these nuts are also called as ‘Extension Nuts.’ 

The Several types of the ‘Coupling Nuts’ are:

1. Left-handed Nuts: These are used to make long joints from a shorter length of the studs using coupling nuts.

2. Sight Hole Nuts: A hole on the side of a nut allows visual verification that the threads are engaged.

3. Reducing Long Nuts: This kind of nut has a bigger end and a smaller end at the fastener that allows joining of two different size thread bolts. 

A ‘Coupling Nut’ is internal finely gripped threads that hold the threaded rods or studs significantly overcoming the compressive stress in the two mating threads and a tensile strength in the coupling nut without loosening over the time period. Also, they are available in the various metal forms such as Brass, Stainless steel & Aluminium.

The Features of Coupling Nut are:

1. Greatly customized with higher dimensional accuracy.

2. Supreme strength with a perfect grip.

3. Black-oxide finish protects from corrosion.

4. Engagement of the studs can be visualized from a small hole.

5. Higher tensile strength and longer durability.  

The Applications Of Coupling Nut are:

1. Engineering Applications.

2. Automotive assemblies.

3. Oil fields.

4. Shipbuilding.

5. Nuclear Projects and Instrumentation.