A coupling nut, also known as an extension nut, is a threaded fastener for joining two male threads, most commonly a threaded rod, but also pipes.
The outside of the fastener is usually a hex so a wrench can hold it. Variations include reducing coupling nuts, for joining two different size threads; sight hole coupling nuts, which have a sight hole for observing the amount of engagement; and coupling nuts with left-handed threads.
These are used to make up long rod assemblies from shorter lengths of rods. The rods are threaded into the coupling nut for a certain distance.
Coupling nut dimensions are described by the Industrial Fasteners Institute in standard IFI-128. It is given a plain finish. It is either cold drawn or hot rolled depending on the bar stock used. Coupling nut threaded with two different thread sizes and profiles are called reducing coupling nuts.
Coupling nuts can be used to tighten a rod assembly inward or to press a rod assembly outward.
Coupling Nut Specifications
M10 Coupling Nut
M12 Coupling Nut
M14 Coupling Nut
M16 Coupling Nut
M18 Coupling Nut
M20 Coupling Nut
M24 Coupling Nut
M30 Coupling Nut
Coupling Nut in Inches
M1/2 Coupling Nut
M5/8 Coupling Nut
M3/4 Coupling Nut
What is a coupling bolt?
A coupling bolt is a mechanical means of holding two halves of a flanged shaft together to properly transfer the torque while maintaining shaft alignment.
What are the coupling nuts used for?
Usually constructed in a hex shape for wrench hold, the most common uses for coupling nuts include tightening rod assemblies or pushing a completed rod assembly outward.
What is a connector nut?
Connector Nuts and Bolts are used for joining any two parts or pieces together, with a finished appearance. Most commonly used to join panels together, such as cabinets, bookcases, and other furniture fixtures. The hex drive allows maximum leverage and force to be applied to the connection.