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Five ways to save money with SKF OK Couplings

When designing an application, performance and efficiency are critical. However, the cost of manufacturing and running the application is also a key consideration. Components that perform, without stretching your budget are essential.  

With a pioneering inbuilt hydraulic fitting mechanism, SKF OK couplings have revolutionised application design by reducing fitting and maintenance costs whilst delivering outstanding levels of performance and efficiency.

Shaft design  

One of the benefits of the SKF OK coupling is its ability to transmit a higher level of torque through the entire contact surface, unlike conventional couplings which use a keyway. This feature facilitates a reduction in the dimensions of both the shaft and coupling, without compromising on power.


Arguably the most unique feature of the SKF OK coupling is its inbuilt hydraulic fitting mechanism. The thin inner sleeve is slid onto the shaft, followed by the thick outer sleeve. Oil is then injected between the sleeves, with a built-in hydraulic jack driving the outer sleeve up to create an interference fit. The need for specialist fitting tools like heaters or oil baths are eliminated, keeping the costs of fitting this coupling to a minimum.

Reduced downtime 

This coupling really is quick and easy to mount and dismount, meaning that downtime is greatly reduced. Very large couplings that could otherwise only be fitted through heating can now be assembled cold, thanks to the OK method.


Maintenance is easy with the SKF OK coupling. With the mounting and dismounting process made as simple as possible, you can reduce the time and costs spent on maintaining machinery, optimising uptime.

Service life 

SKF OK couplings make the most of friction, with torque and axial loads transmitted along the entire surface area of the shaft. The lack of keyway means that there are no stress raisers and no fretting when high shock or reversing loads occur.

In addition to their extensive use on marine propeller shafts, SKF’s OK couplings offer an innovative solution to many applications such as wind turbines, diesel engines and rolling mills. With these couplings connecting over 50,000 shafts across the globe, it’s clear that SKF OK couplings can be relied upon.  

Finally, if you’re considering specifying an SKF OK coupling in your application design, always use an authorised SKF distributor.   

Tom Fowler

Business Development Manager

Tel: 01709 789 955 | Email: couplings&drives@acorn-ind.co.uk (opens new window) | Visit: www.acorn-ind.co.uk/skf