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Coupling

what is meant by coupling?
A coupling is a device used to connect two shafts together at their ends for the purpose of transmitting power. Couplings do not normally allow disconnection of shafts during operation, however, there are torque limiting couplings which can slip or disconnect when some torque limit is exceeded.
The primary purpose of couplings is to join two pieces of rotating equipment while permitting some degree of misalignment or end movement or both. 

Shaft Coupling falls into two main categories: 

  1. Material Flexing and 
  2. Mechanical Flexing. 

Material Flexing CouplingsThe material flexible types obtain their flexibility from stretching or compressing a resilient material, such as rubber, or from the flexing of thin metallic discs or grid. Material flexing couplings typically do not require lubrication, with the exception of grid couplings and operate in shear or compression and are able to accept angular, parallel and axial misalignment.

Examples of material flexing couplings are jaw, sleeve, tire, disc, grid and diaphragm couplings.


Mechanical Flexing Couplings
The mechanical flexing couplings accept misalignment from rocking, rolling or sliding of metal surfaces. All metal mechanical flexing couplings require lubrication.

Examples of mechanical flexing couplings are gear, grid and roller chain couplings.


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