Hardness is a common specification for linear shafts and guides — especially those used with ball and roller bearings, where the guide encounters extremely high loads over very small areas. The hardness of a bearing surface can significantly affect the life of the system and is often accounted for by applying a hardness correction factor […]
Linear bearings
SCHNEEBERGER announces SFERAX Type H.L. linear ball bearing
SCHNEEBERGER Inc. has announced the availability of the new SFERAX Type H.L. linear ball bearing — featuring high-quality engineering at a competitive value point. Developed to support a linear bearing under high loads and high radial torques, the new SFERAX Type H.L. linear ball bearing is ideal for uses ranging from peripheral devices to assembly […]
Gothic arches, tracks, and roller bearings in the context of linear motion
Industry terminology used to describe linear guides and other linear components widely varies. Here we explain three linear-guide phrases and words having multiple meanings — and differentiate how they relate to track-roller linear guides and profiled-rail linear guides. Let’s start by reviewing the multiple linear-motion meanings for Gothic-arch linear bearing. Gothic arches originate from civil […]
How to make linear motion systems cleanroom compatible
While we often talk about the importance of keeping contamination out of linear motion components such as linear guides and screws, when these systems are used in a cleanroom, the goal is just the opposite — to keep these components from introducing contamination into the environment. What exactly is a cleanroom? According to ISO 14644-1:2015, […]
Anti-friction miniature linear guides from PM B.V. now come with a variety of cage options
When building miniature linear-motion systems, design engineers can choose between ball and crossed-roller linear guides. When applied to precision systems, most all of these linear guides have cages to prevent shifting of the anti-friction rolling elements during operation … especially when these linear guides are applied in exacting microscopy, manipulator, and image-scanner applications — for […]
How do miniature profiled rail guides compare to their full-size counterparts?
The basic distinction between “standard” and “miniature” profiled rail guides is the width of the guide rail: profiled rails with a width of 15 mm or less — and the carriages that fit on them — are generally considered “miniature” by bearing manufacturers. (However, some manufacturers also produce 15 mm rail guides in standard versions, as we’ll […]
How to size a spline shaft: Shaft strength in bending and torsion
Choosing a shaft for a traditional linear ball bushing is relatively easy — choose the appropriate diameter, material, and hardness, check the dimensional accuracies and tolerances, and if the shaft is unsupported, perform a beam deflection calculation. But because spline shafts can withstand both radial and torque loads, it’s important to ensure the shaft strength […]
How to calculate linear ball bushing life (and how it differs from other life calculations)
The standard life calculation for linear ball bearings is widely known as: L = bearing life (m) C = rated dynamic load (N) F = applied dynamic load (N) But linear ball bushings often experience operating conditions that aren’t accounted for in the general bearing life equation. To account for these adverse conditions, the life calculation […]
Round-rail linear guide or profile-rail linear guide?
In this article, we outline how to choose a linear guide for your application and environment. By Lindsey Brimage and Eric Schultz | Thomson Industries Ian Miller | Motion Industries Canada Designers of linear motion systems often find themselves weighing the pros and cons of round versus profile (also known as square) linear guides. Many […]
How does shaft hardness affect the life of a linear ball bushing?
A linear ball bushing riding on a round shaft is often compared to a radial ball bearing, with the bushing acting as the outer race of the bearing and the shaft acting as the inner race. But in linear bushing assemblies, the surfaces of both the ball and the shaft are spherical, so contact between […]
