Three different types of guiding variants are used in the area linear axis, each of which is designed for specific applications. You can choose between linear guides, track roller guides and polymer track roller guides, each of which is adapted to specific application requirements. The parameters and requirements mentioned in this article refer to NTN linear axis of the SNR brand.
Linear guides
With regard to linear guides, it can be said that only carriages with an integrated ball chain are used. A linear guide with ball chains is also considered to require no long-term maintenance, offers optimum running behaviour and a very high tolerance compensation capacity, which is particularly important when using parallel axis. Linear guides are suitable for use at speeds of up to 5 meters per second. In general, they also have a low noise level compared to the conventional design.
Track roller guides
The track roller guides are a dust-protected roller system that is integrated into the aluminium profile of the linear axis. In this case, there are ground and hardened steel shafts that are pressed into the aluminium profile and serve as raceways. The rollers are double-row angular contact ball bearing with a profiled outer ring, which are suitable for maximum speeds of up to 15 meters per second. Each guiding system has four, six or eight rollers, half of which are adjustable via eccentrics in order to achieve a clearance-free system. The number of rollers depends on the size and type of linear axis.
Polymer track roller guides
The polymer-track roller guides are special versions designed for applications in the food industry or in wet areas. As these are plastic rollers, their raceways are located directly on the inner surfaces of the aluminium profile. In addition, the clearance-free system in this type is achieved by a spring element integrated into the two-part slider unit. Polymer track roller guides are suitable for applications where speeds of no more than 7 m/s occur. The guiding system always consists of twelve track rollers in order to be able to absorb forces in all directions.
A comparison of the three guiding systems
As already mentioned in the previous paragraphs, all guiding systems naturally have their advantages and disadvantages. The most important aspects are listed again in detail and in direct comparison in the table.
| Advantages | Disadvantages | |
| Linear guide | • Very high load capacity • High rigidity • High tolerance compensation capacity | • Higher costs • Maximum speed of 5 m/s |
| Track roller guide | • Very cost-effective, especially for large strokes • Maximum speed of 15 m/s | • Low load capacity |
| Polymer track roller guide | • Very suitable for use in wet areas • Maximum speed of 7 m/s | • Very low load-bearing capacity |
Track roller guides can be used at 15 m/s at the comparatively highest maximum speeds.
You may also be interested in
Basics of linear motion
Are you new to the field of linear motion and want to get an overview of what is meant by “linear motion“ and what characterises linear systems? Then this article is perfect for you. What is a linear system? A linear system is a machine component that performs a translational movement. To ensure safe use and prevent the ingress of
Types of ball bushings
Ball bushings, which are also known as “linear ball bearings“, are an important product in linear motion. This article deals with the different variants of ball bushings and their properties but first provides you with basic information regarding their history, characteristics and design.
Types of screw drives
You may have heard of ball screws before. These are certainly the best known of the screw drives, but they are not the only ones, as trapezoidal screw drives are a second type. This article will focus on the former, but you will still find everything you need to know about both types here. Design, mode of operation and areas
Types of linear guides
Linear guides are presented below as one type of linear system. Linear guides are among the most important guide systems on the market, mainly because they can be used universally. Types of linear guides A distinction is mainly made between two types of linear guides: Shaft guides and rail guides. Both can be subdivided into different types. Types of shaft
Materials
This article is the right address for you if you want to find out more about the materials used in linear systems. First of all, all components that need to be robust are made of steel, including the rolling elements, the guide rails and the carriages. General information on the materials In addition to steel, various other materials are used
Point, surface and line contact
If you have already dealt with the point and linear contact of rolling bearings, you will recognise a few things. As with rolling bearings, the rolling elements of linear guide systems have either a ball or roller shape. The contact with a raceway (rolling contact) is different for balls and rollers due to their round or elongated shape. With rolling