SKF roller screws offer advantages across the board
2016 November 14, 09:00 GMT
Roller screws require more investment than ball screws, but the extra cost of the products – such as those in SKF’s ‘preferred range’ – is justified through their superior performance in a host of applications.
SKF roller screws continue to be specified in a diversity of industrial applications – proving that many customers are willing to pay a premium for superior performance.
Roller screws are a higher cost than ball screws because they are manufactured to more precise tolerances, and use greater numbers of precision components. This means that they offer many advantages: greater load carrying capacity; superior power density; faster speed and acceleration; greater reliability; and, higher positional accuracy.
“As a consequence, they can be used in more demanding applications,” says Phil Nicholas, Business Development Manager – Linear and Actuation Technology at SKF. “In many cases, the extra investment can be recovered later: the higher load-carrying capacity can lead to a tenfold increase in service life, for instance.”SKF offer a diversity of roller screws, but in order to provide greater value – and shorter lead times – it provides a ‘preferred range’ of the most frequently used sizes of planetary roller screws and recirculating roller screws, along with standard size nuts. Shafts are manufactured according to customer requirements.
Typical machinery that has benefited from the inherent advantages of roller screws includes plastic injection moulding machines, industrial spray guns and medical devices.
In injection moulding machinery, SKF’s Ultra Power roller screws were used in the injection and clamping mechanism of models that exert a clamping pressure of up to 200 tonnes. At the same time, they boosted energy efficiency – and improved cleanliness by banishing hydraulic oil.
Roller screws have also been used in factory automation systems – for operations such as gluing, riveting and welding – thanks to their accuracy and repeatability, faster resetting, reduced downtime and compactness. In microchip encapsulation, the reduced footprint, increased duty cycle and longer lifetime, along with reduced maintenance, are the main reasons for using them.
Away from engineering production, they have even found use in the electromechanical drive of a radiotherapy couch, which must be positioned accurately before gamma rays are directed into the patient.On top of this, there are many examples in the marine, offshore, pulp and paper, and aerospace industries.