A coupling is a device used to connect two shafts collectively at their ends for the intended purpose of transmitting power.
Couplings do not normally allow disconnection of shafts during operation, however there are torque limiting couplings that may slip or disconnect when some torque limit is exceeded.
The primary reason for couplings is to join two pieces of rotating equipment while permitting some extent of misalignment or end movement or both.
By careful selection, installation and maintenance of couplings, substantial savings can be manufactured in reduced maintenance costs and downtime.
3 main types of couplings:
1. Rigid coupling a rigid coupling is usually a unit of equipment used to become listed on two shafts within a electric motor or mechanical system. It could be used for connecting two separate systems, like a motor and a generator, or to restoration a connection within an individual program. A rigid coupling may also be added between shafts to reduce shock and wear at the main point where the shafts meet.
When joining shafts within a machine, mechanics can choose between flexible and rigid couplings. While flexible units give some movement and give between the shafts, rigid couplings will be the most effective choice for exact alignment and protected hold. By exactly aligning both shafts and holding them firmly in place, rigid couplings help to maximize performance and raise the expected life of the machine. These rigid couplings can be found in two basic styles to fit the wants of different applications. Sleeve-style couplings are the least expensive and easiest to use. They consist of a single tube of materials with an inner diameter that’s equal in proportions to the shafts. The sleeve slips over the shafts therefore they fulfill in the center of the coupling. A number of set screws can be tightened so they touch the very best of each shaft and hold them set up without passing all the way through the coupling.
Clamped or 
compression rigid couplings come in two parts and match together around the shafts to form a sleeve. They provide more flexibility than sleeved models, and can be utilized on shafts that are fixed in place. They often are large enough to ensure that screws can move completely the coupling and into the second half to make sure a secure hold.
Flanged rigid couplings are designed for heavy loads or commercial equipment. They consist of short sleeves surrounded by a perpendicular flange. One coupling is positioned on each shaft so the two flanges fall into line face to face. A number of screws or bolts can then be installed in the flanges to hold them jointly. Because of their size and durability, flanged units can be used to bring shafts into alignment before they are joined up with jointly. Rigid couplings are utilized when specific shaft alignment is required; shaft misalignment will impact the coupling’s performance along with its life.
2. Flexible coupling versatile couplings are used to transmit torque in one shaft to some other when both shafts are somewhat misaligned. Versatile couplings can accommodate varying levels of misalignment up to 3° and some parallel misalignment. Furthermore, they can also be used for vibration damping or sound decrease.This coupling is used to safeguard the driving and driven shaft members against harmful effects produce because of misalignment of the shafts, sudden shock loads, shaft expansion or vibrations etc.
3. Torque limiter coupling designed to slip the torque from the shaft to prevent harm to the engine or the application
What is the difference between rigid coupling and flexible coupling?
Couplings are split into categories: Rigid and Flexible. In comparison withflexible couplings, rigid couplings have limited program. Rigid couplings do not have the ability to compensate for shaft misalignments and are therefore used where shafts already are positioned in precise lateral and angular alignment.
What are the benefits of flexible coupling?
Versatile couplings accomplish the purpose of any coupling, but their advantageover rigid couplings is definitely they accommodate the unavoidable misalignment between shafts in some machinery. Flexible couplings also allow for a amount of axial movement between the coupled shafts as may occur due to thermal expansion.
What exactly are the types of coupling?
What is Coupling? Types of Shaft Couplings
Rigid Couplings.
Versatile or Compensating Couplings.
Clutches to are a type of Coupling – We can the dealing on them separately.
Flanged Pin Bush Couplings.
Bibbly Coupling.
Gear Tooth Coupling.
Tyre couplings.
Elastomeric Couplings – This consists of jaw type and S-flex couplings.
Couplings are devices used for connecting two shafts together and are divided into two groups: Rigid and Flexible. Both are used for the objective of transmitting power, rigid couplings becoming even more limited in applications when compared with versatile couplings. Rigid couplings are utilized where shafts already are positioned in precise lateral and angular alignment. Their design does not allow for any misalignment between shafts, but are usually able to transmit even more power than flexible couplings. Flexible couplings are designed to accommodate misalignment between shafts and different types of load conditions. Many styles and types of couplings can be found. For successful coupling selection, application conditions should be clearly understood.