Ball screws are used in a wide variety of applications, but some of the most challenging are those on the extreme ends of the performance spectrum – from large diameter, large lead screws for machine tools, to screws with small diameters and very fine leads for optical and medical applications. For very small, high-precision movements, designers and engineers often turn to miniature ball screws.
While there’s no industry standard for what classifies a screw as “miniature,” most manufacturers apply the designation to screws with a diameter smaller than 16 mm, while others include 16 mm screws in their “miniature” product line. To further segment the range of sizes, screws with a diameter smaller than 6 mm are sometimes referred to as “sub-miniature” or “ultra miniature.”
In some regards, miniature ball screws are the same as their larger, “standard” counterparts. For instance, miniature ball nuts are offered in many of the same styles as standard ball nuts, including flanged, cylindrical (also referred to as “compact” or “slim”), or with a threaded end for easy mounting into a carriage or table assembly. Ball recirculation can be done inside the ball nut or with external recirculation methods. Lead accuracies and preload classes follow the same designations regardless of the screw diameter. And sizing parameters, such as L10 life calculation, buckling load, and critical speed, are the same for both miniature and standard ball screws.
Miniature ball screws, like standard versions, can be manufactured by either rolling or grinding the screw threads. Screw diameters below 8 mm are commonly produced by grinding, although some manufacturers offer screws as small as 6 mm diameter in rolled versions. In some miniature screw sizes, the journal diameter of the screw is too small to accommodate an appropriately sized end bearing. To address this, manufacturers can friction weld a larger journal onto the screw end, providing a sufficient journal for the support bearing.
Here below is our Capability of the ball screw parts:
Quality Certification: ISO9001:2008, TS 16949. 
Products: Ball screws in rolled or ground type, ball screw nuts, and linear guideways. 
Product range: Ø5 mm to Ø160 mm with different leads and different lengths 
Lead range: 01 to 50mm 
Length: 7m Max 
Material: GCr15, 40Cr, SUS303, SUS316, 9Cr18,or other tailored materials per your requirement. 
Accuracy Grade: C1, C3, C5, C7. 
Lead time: 3-8wks 
Advantages: High speed & mechanically efficiency, low noise, heavy load, long life time, low power consuming mechanism, low starting torque.