A coupling nut, also known as an extension nut, is a threaded connector designed to join two male-threaded rods, pipes, or comparable components together. Coupling nuts work by engaging its internal threading with the external threads of the parts being joined. Coupling nuts serve to lengthen threaded rods or pipes, or to connect two components along a shared axis. They play a vital role in establishing durable or semi-durable connections across different mechanical and structural applications.

Most coupling nuts feature a hexagonal shape, which enables easy manipulation using a standard wrench. The internal threading extends through the entire nut length, delivering robust and reliable connections. The dimensions and wall thickness of coupling nuts vary based on specific requirements and the size specifications of the parts being connected.

Types of Coupling Nuts

Standard coupling nuts feature identical threading dimensions at both ends. They join components sharing the same thread specifications, enabling threaded rod or pipe extensions. The consistent threading ensures dependable connections, making these nuts suitable for diverse industrial uses.

Reducing Coupling Nuts incorporate different thread sizes at each end. This design enables the connection of components with varying thread dimensions, facilitating diameter transitions. They can effectively link larger threaded components to smaller ones, for mixed-thread configurations.

Inspector Coupling Nuts incorporate holes that allow for verifying threaded component engagement. This feature proves valuable when precise alignment and connection are essential. The ability to view the connection minimizes damage and over-tightening.

Hex coupling nuts employ a hexagonal design, allowing use with conventional wrenches. This is the most commonly used design.

Round coupling nuts have a cylindrical profile and excel in applications with space constraints, offering compact connection solutions.