A shaft coupling is used to transmit power from a driving shaft to a driven shaft. The shafts are arranged so that one is an extension of the other, or at an angle to each other.
Couplings transmit torques without play and can also compensate for radial and axial misalignment, even at high levels of rigidity.
It is possible to have a rigid connection or a flexible connection that is able to dampen the above mentioned misalignment and vibrations. Shaft couplings are almost maintenance-free and fulfil their task to a high degree of precision throughout the entire service life. They are therefore also often used in situations where the drive must be extremely precise.
Shaft couplings are available in different versions, for example as: tyre coupling, flexible claw coupling, (curved) tooth coupling, fixed coupling, disk clutch, elastic coupling, fluid coupling, pin coupling and cylindrical clamping elements.
Which option is the correct one depends mainly on the power to be transmitted, the field of application and the working environment. Shaft couplings, which must be resistant to moisture, rust formation or other (aggressive) ambient conditions, are also available in stainless steel or with special surface treatment.
Thanks to the extensive range of products, a suitable solution is available for each particular application, because, in addition to transmitting torque, each type of shaft coupling has certain ancillary functions: torsional stiffness (important for positioning accuracy), rupture-proof (e.g. for lifting applications) or not rupture-proof, vibration-dampening (for internal combustion engines) and compensating alignment errors (parallelism errors or angle errors).
Sometimes the installation options also play a role (e.g. mounted axially or radially). If the situation requires it, shaft couplings can also be counterbalanced.
If a distance must be bridged between the shafts, components known as spacer couplings can be used. The shaft offset is often referred to as DBSE (distance between shaft ends).
There are also shaft couplings that can be used at high ambient temperatures (e.g. couplings completely made from metal) or in potentially explosive areas where the components must meet the FRAS and/or ATEX guidelines.
Shaft couplings can be found in virtually every industry: (petro)chemicals, the food and drug industries, mechanical engineering, maritime applications, and by no means least in agriculture and forestry, as well as fisheries.
Various standards are relevant for shaft couplings, for example, DIN 740, DIN 115 and DIN 116.