SKF's miniature profile rail guides are suitable for use in high-precision applications and offer equal load carrying capacity in all directions. The guides consist of a rail with four ground raceways on which one or more slide units can travel with unlimited stroke. The slide units are made of hardened bearing-quality steel, with ground ball circulation paths.
Thanks to a simple design, featuring one-piece ball return paths, mounting is said to be very easy. The ribbed underside of the rail further simplifies mounting in a suitably machined groove. Holes are provided in the flanges for direct mounting of machine components onto the rail.
The steel balls circulate in four paths between the rail and slide unit, and the square configuration of the raceway results in a guidance system with good rigidity and a high dynamic load rating in all four load directions. An external ball return path enables the use of an extra large radius, ensuring quiet running even at higher speeds. An external return path also avoids unnecessary weakening of the slide unit and therefore endows the system with greater stiffness.
The SKF miniature profile rail guides are manufactured in three accuracy classes: P1, P3, and P5. Each of these offers progressively greater dimensional tolerance and deviation between paired rails. Miniature profile rail guides are available in two different preload classes and preloaded guides have approximately twice the stiffness of those without preload. The maximum standard length for miniature profile rail guides is 500mm, though longer runs can be constructed by joining separate lengths together.