Date Published:Jul. 08. 2016

About Shaft Couplings

A shaft coupling is a mechanical component that connects the drive shaft and driven shaft of a motor, etc., in order to transmit power. Shaft couplings introduce mechanical flexibility, providing tolerance for shaft misalignment. As a result, this coupling flexibility can reduce uneven wear on the bearing, equipment vibration, and other mechanical troubles due to misalignment.

Shaft couplings are available in a small type mainly for FA (factory automation) and a large casting type used for large power transmission such as in wind and hydraulic power machinery.
In NBK, the former is called a coupling and the latter is called a shaft coupling. Here, we will talk about the shaft coupling.

For small couplings for FA,click here.

Why Do We Need Shaft Couplings?

Even if the motor and workpiece are directly connected and correctly fixed, slight misalignment can occur over time due to changes in temperature and changes over a long period of time, causing vibration and damage.
Shaft couplings serve as an important link to minimize impact and vibration, allowing smooth rotation to be transmitted.

Flexible Flanged Shaft Couplings


  • These are the most popular flexible shaft couplings in Japan that comply with JIS B 1452-1991 "Flexible flanged shaft couplings".
  • A simple structure made of a flange and coupling bolts. Easy to install.
  • The bushing between the flange and coupling bolts alleviates the effects of torque fluctuation and impacts during startup and shutdown.
  • The bushing can be replaced simply by removing the coupling bolt, enabling easy maintenance.
  • Permits lateral/angular misalignment, and reduces noise. Prevents the thrust load from being transmitted.
  • 2 types are available, a cast iron FCL type and a carbon steel FCLS type.


Product Introduction Improved productivity/workability Vibration prevention/high precision Machine Tools Semiconductor Manufacturing Equipment Food Machinery Automotive Manufacturing Process Medical Equipment FA Devices Couplings