About Shaft Couplings

A shaft coupling is a mechanical component that connects the drive shaft and driven shaft of a electric motor, etc., in order to transmit electrical power. Shaft couplings present mechanical flexibility, featuring tolerance for shaft misalignment. Subsequently, this coupling overall flexibility can reduce uneven put on on the bearing, products vibration, and various other mechanical troubles due to misalignment.

Shaft couplings can be found in a tiny type mainly for FA (factory automation) and a big casting type used for huge power tranny such as for example in wind and hydraulic power machinery.
In NBK, the former is called a coupling and the latter is named a shaft coupling. Right here, we will speak about the shaft coupling.
Why Do WE ARE IN NEED OF Shaft Couplings?
Even if the motor and workpiece are immediately connected and effectively fixed, slight misalignment can occur over time because of improvements in temperature and changes over a long period of time, triggering vibration and damage.
Shaft couplings serve as an important connect to minimize effects and vibration, allowing smooth rotation to end up being transmitted.
Flexible Flanged Shaft Couplings
Characteristics
These are the most famous flexible shaft couplings in Japan that comply with JIS B 1452-1991 “Flexible flanged shaft couplings”.
A simple structure manufactured from a flange and coupling bolts. Easy to install.
The bushing between your flange and coupling bolts alleviates the consequences of torque fluctuation and impacts during startup and shutdown.
The bushing can be replaced by just removing the coupling bolt, enabling easy maintenance.
Permits lateral/angular misalignment, and reduces noise. Prevents the thrust load from simply being transmitted.
2 types are available, a cast iron FCL type and a carbon steel?FCLS type Flexible Shaft Couplings

Shaft Coupling Considerations
In choosing couplings a designer first needs to consider motion control varieties or power transmission types. Most action control applications transmit comparatively low torques. Power tranny couplings, in contrast, are created to carry average to excessive torques. This decision will narrow coupling choice relatively. Torque transmission along with optimum permissible parallel and angular misalignment ideals are the dominant considerations. The majority of couplings will publish these ideals and using them to refine the search should help to make deciding on a coupling style simpler. Optimum RPM is another essential attribute. Optimum axial misalignment could be a consideration aswell. Zero backlash can be a significant consideration where responses is employed as in a motion control system.
Some power transmitting couplings are designed to operate without lubricant, which may be a plus where maintenance is a concern or difficult to execute. Lubricated couplings quite often require covers to keep the grease in. A large number of couplings, including chain, equipment, Oldham, etc., are available either as lubricated metal-on-metal types and as steel and plastic hybrids where usually the coupling element is made from nylon or another plastic material to eliminate the lubrication requirements. You will find a reduction in torque potential in these unlubricated varieties compared to the more conventional designs.
Important Attributes
Coupling Style
Almost all of the common variations have already been described above.
Maximum RPM
Most couplings have a limit on the maximum rotational acceleration. Couplings for high-quickness turbines, compressors, boiler feed pumps, etc. generally require balanced patterns and/or balanced bolts/nuts allowing disassembly and reassembly without increasing vibration during procedure. High-speed couplings can also exhibit windage effects in their guards, which can bring about cooling concerns.
Max Transmitted Horsepower or Torque
Couplings are often rated by their optimum torque capacity, a measurable quantity. Electric power is a function of torque times rpm, consequently when these ideals are stated it is usually at a specified rpm (5HP @ 100 rpm, for example). Torque values will be the additionally cited of both.
Max Angular Misalignment
Among the shaft misalignment types, angular misalignment potential is usually stated in degrees and represents the maximum angular offset the coupled shafts exhibit.
Max Parallel Misalignment
Parallel misalignment capacity is often given in linear systems of inches or millimeters and represents the maximum parallel offset the coupled shafts exhibit.
Max Axial Motion
Sometimes called axial misalignment, this attribute specifies the utmost permissible growth between the coupled shafts, offered generally in inches or perhaps millimeters, and may be due to thermal effects.