Technical guides
Linear guides are precision mechanical components designed to provide controlled linear motion, with high precision and low friction.
These products are the ideal solution for industrial applications requiring the guidance and support of loads and moments in all directions.
Linear guides consist of ball or roller recirculating carriages that run along profiled, hardened rails, ensuring long strokes, zero play and repeatable positioning.
Structure and operating principle of linear guides
A linear guide mainly consists of three parts:
- Carriage: the moving component that travels along the rail;
- Rail: the linear element along which the carriage moves;
- Balls or rollers: the rolling elements positioned between the carriage and the rail, enabling low-friction linear motion.
The guide can also be fitted with additional accessories, such as an integrated solid grease lubrication module. This innovative lubrication system consists of a lubricant-impregnated resin pad secured to the carriage end cap with two screws.
What is the advantage of this module? During movement, the pad gradually releases oil onto the rail surface, ensuring continuous lubrication over an extended period.
Advantages of linear guides
Ball and roller recirculating linear guides offer numerous advantages, including:
- high rigidity and positioning accuracy;
- long service life and consistent motion precision;
- fast and quiet movement;
- dimensional interchangeability;
- reduced maintenance requirements and easy lubrication;
- high load-carrying capacity and moment resistance;
- effective sealing and protection against dirt and contaminants.
Applications of linear guides
Thanks to their versatility and numerous advantages, these mechanical components are used across a wide range of industrial sectors, from machine tools to the food industry, industrial automation, medical and pharmaceutical applications, logistics, automotive and electronics.
Types of JFK linear guides
JFK linear guides are available in various configurations, designed to meet specific requirements in terms of load capacity, precision, space constraints and operating conditions.
JFK Group’s range of linear guides includes four main types:
- GH standard series
- GE low-profile series
- GM miniature series
- GR roller series
GH standard series – Ball recirculating linear guides
The GH series from JFK Group includes linear guides with four ball recirculation circuits and is considered the reference series for the most common industrial applications. Its structural design is optimized to ensure high load-carrying capacity, rigidity and positioning accuracy, also thanks to its integrated self-alignment function.
The GH series linear guides stand out for:
- uniform load-carrying capacity in all directions, ensured by the 45° arrangement of the four recirculation circuits;
- dimensional interchangeability;
- high rigidity in all directions;
- compact design and flanged configuration (also available with a long carriage for applications requiring high load-carrying capacity).
In addition to the GHH and GHW configurations, featuring compact and flanged designs, this product family also includes the GHL series, which differs from the previous configurations by its low-profile carriage, designed to reduce overall height.
GE low-profile series – Ball recirculating linear guides
The GE series four-circuit ball recirculating linear guides from JFK Group differ from the GH series thanks to their low-profile design, featuring a reduced height of both the carriage and the rail. This characteristic makes them particularly suitable for applications with limited installation space, where a lower load-carrying capacity is required compared to the GH series.
Available with compact, flanged and short carriage configurations, the GEH and GEW linear guides ensure high rigidity in all directions, dimensional interchangeability and uniform load-carrying capacity, thanks to the 45° arrangement of the four ball recirculation circuits.
GM miniaturized series – Ball recirculating linear guides
The JFK Group's miniaturized GM series consists of linear guides with two recirculating ball circuits and Gothic arch-shaped raceway profiles, capable of supporting loads in all directions while ensuring precision and rigidity.
Thanks to their compact and lightweight design, these guides are particularly well-suited for applications where a small footprint is a priority, despite having a lower load capacity than the larger series.
Compared to the GMN series, the GMW miniaturized linear guides feature a carriage and a rail that are wider. This configuration allows for a significant increase in load capacity with respect to torsional moments.
GR roller series – Roller recirculating linear guides
The GR series linear guides from JFK Group use cylindrical rollers as rolling elements, significantly increasing rigidity and load-carrying capacity compared to ball recirculating versions.
Featuring four roller recirculation circuits with a 45° contact angle, the GR series guides are available in both assembled and interchangeable versions. The range includes the GRH model, with a compact carriage, and the GRW model, with a flanged carriage.
Their high rigidity and excellent load-carrying capacity make these components the ideal choice for heavy-duty applications involving high radial loads and significant bending moments.
Compared to ball recirculating linear guides, rollers also distribute loads and stresses more effectively, ensuring high precision and positioning accuracy even under particularly demanding operating conditions.
How to choose a linear guide
Choosing the most suitable linear guide for a specific application requires evaluating several key parameters, including:
- applied load
- service life
- space constraints
- speed
- duty cycle
- precision
- rigidity
In particular, the following aspects should be considered when selecting a linear guide:
- Application field: identify the industry, machine type and specific operating conditions.
- Precision class: select the appropriate class based on the accuracy required by the application.
- Dimensions and space constraints: determine the guide cross-section, rail length and number of carriages required, taking into account the available space and the load to be supported.
- Maximum applied load: calculate the nominal load and moments that the guide will need to withstand.
- Preload: determine the preload value based on the required rigidity and the available mounting surfaces.
- Service life: estimate the guide’s operating life by considering speed, duty cycles and operating conditions.
- Lubrication: choose the most appropriate lubricant (grease or oil) and assess the presence of dust, contaminants, moisture, high temperatures or other environmental factors that may affect the linear guide’s operating conditions.
Contact our technical department to identify the solution that best meets your needs.
